# XPA-7 considered to be an upgrade?



## Talley (Dec 8, 2010)

I'm thinking of picking up a XPA-7 to replace my showcase. The main reason is it's two channel 500w capability. Another reason is having a bit more headroom of 200w vs 125w the showcase gives me (all channels driven). I can offload the krell for around the same price as buying the XPA new so it's a wash with cost.

Not sure if there is a sound difference at all which is another thing I want to do is listen to each also. However the Krell has been tested to still only deliver 136w & 8ohms with 2 channel driven VS the emotiva amp running 500w/8ohms.

Surely that would give me some improvements on the 2 channel listening. Another option is to just go a bit more expensive and do an XP*R*-2 & XPA-3 or even just doing 5 XPA-100s... I'm not stuck on emotiva either I'm sure there are other options.

I was looking at the XPR-5 but is no longer available and harder to find used... Any other ideas would be appreciated. Thanks,


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## Talley (Dec 8, 2010)

I'm not against monoblocks either... I can add a few dedicated circuits easy so they can all have dedicated circuits.


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## tonyvdb (Sep 5, 2007)

What kind of levels are you running at Talley? Those SVS ultras don't need that much power, at 110watts you would be in the 100+ db range. :gulp:


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## Talley (Dec 8, 2010)

tonyvdb said:


> What kind of levels are you running at Talley? Those SVS ultras don't need that much power, at 110watts you would be in the 100+ db range. :gulp:


What?... talk louder please :rofl:

there is a reason for upgrade...


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## luisv (Feb 27, 2014)

If you can wait a bit, Emotiva should be releasing more info at CES about their modular Gen 3 Amps. You're supposed to be able to add up to 7 channels in a single chassis and they are supposed to be more efficient that the GEN2s.


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## Talley (Dec 8, 2010)

luisv said:


> If you can wait a bit, Emotiva should be releasing more info at CES about their modular Gen 3 Amps. You're supposed to be able to add up to 7 channels in a single chassis and they are supposed to be more efficient that the GEN2s.


Not sure if I want the non toroidal power supply setup they are moving to.

Honestly their XPR-5 would be a perfect setup for me


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## luisv (Feb 27, 2014)

I'm in the same camp as you are concerning the new power supply, but if you purchase the Gen 3 and only buy 5 modules, you still have room for growth within the same chassis. I'm making this statement on the little bit of info they released thus far, so just throwing it out there for ya.


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## Talley (Dec 8, 2010)

luisv said:


> I'm in the same camp as you are concerning the new power supply, but if you purchase the Gen 3 and only buy 5 modules, you still have room for growth within the same chassis. I'm making this statement on the little bit of info they released thus far, so just throwing it out there for ya.


Buying the XPA-7 gives me 7 channel. The new Gen 3 can only go up to 7 channels. No additional room to grow other then adding a second/third amp.


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## willis7469 (Jan 31, 2014)

Talley said:


> Buying the XPA-7 gives me 7 channel. The new Gen 3 can only go up to 7 channels. No additional room to grow other then adding a second/third amp.



Just curious if this matters for doing PLIIz? I don't think you'd be able to successfully do PLIIx unless you moved the LP off the wall at least 5'. I've been in 7ch systems with the rear surrounds right above the LP. It's not good. I know you don't care about atmos for a few years, so that's why I was wondering. 


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## Talley (Dec 8, 2010)

willis7469 said:


> Just curious if this matters for doing PLIIz? I don't think you'd be able to successfully do PLIIx unless you moved the LP off the wall at least 5'. I've been in 7ch systems with the rear surrounds right above the LP. It's not good. I know you don't care about atmos for a few years, so that's why I was wondering.
> 
> 
> Sent from my iPhone using Tapatalk


I don't need 7 channels.... just 5. I would however buy a XPA-7 over the XPA-5 just due to the 2 channel capability of the 7. 520w/channel would scream headroom for loud transients.

I know my Krell does good. Just looking at some other options. I wouldn't mind doing monoblocks either.

So... anyway... on these amps like my Krell it tested 105w for all channel driven at .1 thd and 136 all channel at 1%. I know this is more than enough but the XPA-7 would double my all channel and 5x the 2 channel.


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## Talley (Dec 8, 2010)

I broke down....

Purchased an XPA-7. Will be very curious to the differences between the krell and this. I'll have both amps hooked up and will have speaker cable on each out to the speakers so I can quickly swap the speaker cables around from one amp to the other for 2channel listening. Best I can do without an a/b switch thing.

Not sure how long it'll take to come in but I finally will get to see if there is any audible differences from 150w to 500w in 2channel mode


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## Savjac (Apr 17, 2008)

Well congrats, Emotiva ships out quick and you should have it before the weekend for sure.
Looking forward to hearing from you

Oh and have someone help you move it around, these Emo's are beasts.


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## Talley (Dec 8, 2010)

Savjac said:


> Well congrats, Emotiva ships out quick and you should have it before the weekend for sure.
> Looking forward to hearing from you
> 
> Oh and have someone help you move it around, these Emo's are beasts.


Thanks.

yes the Krell is 65lbs and the XPA-7 is 96lbs. I hope the amp can roll easy haha.


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## Talley (Dec 8, 2010)

And wow... literally only one hour after I placed my order the 20% holiday sale went away and the XPA-7 is now back to 1599.

Talk about timing


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## Lumen (May 17, 2014)

You probably already thought of this, but just curious - will your rack support the weight, or will the amp sit on the floor?


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## Talley (Dec 8, 2010)

Lumen said:


> You probably already thought of this, but just curious - will your rack support the weight, or will the amp sit on the floor?


I'm good. My rack is a regular flex type rack using all thread and currently 1.5" MDF. I've jumped up and down on this thing and my fat butt weighs 230lbs. It's stout. 

I have plans to change the MDF out for Maple... and use copper tubing to conceal the all thread. I think it'll look real sweet then. I'll polish the copper and then clear coat it. and will stain the maple a really dark mahogany color. When I change it out I'll actually make the rack foot print smaller as it's currently 48"x24". I'll shrink it down to about 20" x 38"

One thing for sure... this XPA-7 is mighty tall at 9 7/8" I may have to change my design up a tad more to accommodate the size.

Until then it will sit right next to the Krell. I plan on auditioning the two side by side over two weeks and make a decision then.


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## Savjac (Apr 17, 2008)

Talley said:


> Thanks.
> 
> yes the Krell is 65lbs and the XPA-7 is 96lbs. I hope the amp can roll easy haha.


Well this may be an issue as the XPA is rectangular so I am thinking rolling may not be an option.

I was ultimately not able to roll mine, maybe Lumen knows a way. :rofl:


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## Savjac (Apr 17, 2008)

Talley said:


> And wow... literally only one hour after I placed my order the 20% holiday sale went away and the XPA-7 is now back to 1599.
> 
> Talk about timing


I sent you a PM Talley, just so you know.


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## Talley (Dec 8, 2010)

I did find this out:

Krell Showcase Amplifier has all input sections are class A design while the amplification section is A/B. The power on the krell for 2 channel driven is 140w for .1 thd vs. xpa-7 is 520w. roughly 4 times more potent in two channel. Krell has 105w for 6 channel driven vs. xpa-7 is 200w all 8ohms of course.

Powerwise I know it'll be more headroom but not sure of the "sonic" differences.


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## Lumen (May 17, 2014)

Savjac said:


> Well this may be an issue as the XPA is rectangular so I am thinking rolling may not be an option.
> 
> I was ultimately not able to roll mine, maybe Lumen knows a way. :rofl:


I think you may have just invented the solid-state equivalent of "tube rolling" :laugh:


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## Lumen (May 17, 2014)

Talley said:


> ...Will be very curious to the differences between the krell and this. I'll have both amps hooked up and will have speaker cable on each out to the speakers so I can quickly swap the speaker cables around from one amp to the other for 2channel listening. Best I can do without an a/b switch thing...





Talley said:


> ...Powerwise I know it'll be more headroom but not sure of the "sonic" differences.


Level-matching is key, as you know. "Calibrating" the processor's volume control for a given SPL would work. What do you think about recording the volume setting when feeding a test signal through the chain for each amplifier? Then you could just return the control to that setting when the corresponding amp is in the chain. Any holes in my plan?


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## tonyvdb (Sep 5, 2007)

What! none of you have a hoverboard you can use to move it??


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## Talley (Dec 8, 2010)

Lumen said:


> Level-matching is key, as you know. "Calibrating" the processor's volume control for a given SPL would work. What do you think about recording the volume setting when feeding a test signal through the chain for each amplifier? Then you could just return the control to that setting when the corresponding amp is in the chain. Any holes in my plan?


Pink noise and SPL meter was my plan. obviously being the emotiva amp is 1.4v input krell is 1.55 and the gain on krell is 26.2db and emotive is 29....

will make a difference. I'll find the pink noise for each amp to be equal and will then know the difference.


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## willis7469 (Jan 31, 2014)

Come on talley! I'm waiting!


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## willis7469 (Jan 31, 2014)

Oh yeah, congratulations!


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## Talley (Dec 8, 2010)

willis7469 said:


> Oh yeah, congratulations!
> 
> 
> Sent from my iPhone using Tapatalk


No Congrats yet. Just a demo.... I'll give it two weeks of some pretty critical listening. I have my room treated fairly decent now and have spent enough time to get the speaker placement and DIRAC setup w/ crossover to where I'm satisfied. 

I've done everything I can to help me listen to these amps.... but first thing is to get the XPA hooked up and play some music through them at light levels for a good 48hrs too.


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## Talley (Dec 8, 2010)

Using my new Fluke 289 logging meter I turned the amp off... put the XMC-1 into reference stereo and played some Pink Floyd - Two suns in the sunset on their Final Cut album. 

)This was the AC voltage logging at a resolution of 8 samples per second during about 2:20-~3:05 of the track. Heavy bass... kick drum, snare... sustained strong bass. Good stuff.

The logging picked up peak voltage outputting out of the RCA jack (going into the amp) around .8v. One thing to note this is with the volume set to 0db on the XMC-1.

When I switched over to the min/max peak readout... I started seeing some peaks hit 1.2v then 1.5v then 2.2v and finally thoughout the entire song it hit what you read here. Unfortunately I haven't found a way to log Peak yet... I think there is a way but gotta play around with the meter some.

Anyway... what this means is that for most of the song... music was playing at 0db (my amp was off nothing was moving out of the xmc-1) and the RCA voltage was hovering around .2v-.5v for most all of the song. when the peaks hit... it was obvious on the meter the voltage would spike. the min/max Peak resolution is very fine at 250 micro seconds (0.00025s) of a output... my math is rough on this I need to brush up but I'm pretty sure that is clipping the Krell who has a voltage sensitivy of 1.5v. I need to do some amp gain math on this or maybe someone can help me out.

For that micro second of an instant... 2.7V peak. Doesn't this tell me that for that very peak instant... for a non clipping scenario that you want whatever wattage that works out to be of headroom? My head being tired tells me this is some 600 watts it's commanding. Help me out here guys. I picked 0db on the xmc because this is a gain of 1.0 on it's preamp gain structure.


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## Talley (Dec 8, 2010)

Just read an article and it mentioned playing a 20-20k pink noise and using that to watch the RCA voltage as it will be commanding the entire frequency range and you can see at what point will the rca produce peak voltage to the amp so you can determine maximum volume before amp clipping.

I still have to freshen up on amplifier gain math so I can figure all this out.


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## Tonto (Jun 30, 2007)

In real world listening, how loud are your ultras playing @ that level?


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## Talley (Dec 8, 2010)

Tonto said:


> In real world listening, how loud are your ultras playing @ that level?


well at 0db... peaks hit 102ish but I don't listen at those levels rarely. 

I watch my SPL meter closely and normally play music after Dirac calibration around the -16db to around -8db on average on the volume which usually I get it close to around 85db where the music bounces between 80-90db.

all depends on the music... and the actual disc too... it varies on disc.


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## Savjac (Apr 17, 2008)

Talley said:


> well at 0db... peaks hit 102ish but I don't listen at those levels rarely.
> 
> I watch my SPL meter closely and normally play music after Dirac calibration around the -16db to around -8db on average on the volume which usually I get it close to around 85db where the music bounces between 80-90db.
> 
> all depends on the music... and the actual disc too... it varies on disc.


Might we say that you listen at a level that pleases your mood at the moment ?
I dont thank any of us, well most of us, try not to listen at levels that would render the sound of a Navy jet quiet by comparison. 

In reality, I think you should be happy with either amp in the real world of listening to music or movies. Yes there may a bit more oomph with a bigger amp on large crescendos such as those heard on the Gladiator soundtrack. I think listening and allowing yourself to be moved by the music is more fun than looking at a meter. :heehee:


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## Talley (Dec 8, 2010)

Savjac said:


> Might we say that you listen at a level that pleases your mood at the moment ?
> I dont thank any of us, well most of us, try not to listen at levels that would render the sound of a Navy jet quiet by comparison.
> 
> In reality, I think you should be happy with either amp in the real world of listening to music or movies. Yes there may a bit more oomph with a bigger amp on large crescendos such as those heard on the Gladiator soundtrack. I think listening and allowing yourself to be moved by the music is more fun than looking at a meter. :heehee:


"Your ears can never undo what is better, however, your ears are naive because they don't know what is better if you don't give them better."

I've never heard 500w of headroom playing music. Only limited by ~140w. Currently I am satisfied... because my ears haven't heard better. If putting the more headroom of an amp in the system yields cleaner transients that is presented by audible differences then good. But your ears hear less of subtle goodness then subtle badness meaning put the new in the system... listen for two weeks then move back. Then go back and forth.

At some point... if there is nothing audible from more headroom... XPA will go back and I will repair my Krell as it has a sense of "i spent alot of money". lol... or chances are the XPA provides SOMETHING audible in the good then I keep it. 

The crazy thing is... my critical listening is non amplified music. Solo cello... harry james... acoustic guitar and the upright bass are my favorites with some horns mixed in for good measure. it'll be tough to pick out the winner... and it's really not the case. If the xpa offers nothign to the plate but takes none... it'll be the keeper because the Krell repair issue. Should be interesting. BUT... at least I'll finally hear 140w vs 500w. 

No instrument can tell me which is better other than my ears and my easily tricked brain. :nono:


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## Talley (Dec 8, 2010)

and I was extremely disappointed in the gladiator soundtrack... or at least the audio on the movie.

clip city


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## Savjac (Apr 17, 2008)

Talley said:


> "Your ears can never undo what is better, however, your ears are naive because they don't know what is better if you don't give them better."
> 
> I've never heard 500w of headroom playing music. Only limited by ~140w. Currently I am satisfied... because my ears haven't heard better. If putting the more headroom of an amp in the system yields cleaner transients that is presented by audible differences then good. But your ears hear less of subtle goodness then subtle badness meaning put the new in the system... listen for two weeks then move back. Then go back and forth.
> 
> ...


Youre preaching to the choir Mr. T, I have done this for over 40 years. As you practice and listen you can hear subtle differences much easier. The music you mention has substantial dynamics involved, particularly Harry James. 

May I ask if you listen to live amplified music much ? This is really the only way to discover which equipment sounds like the real deal. I think we have to attend several times a month to keep those ears in tune, otherwise we loose grip on accuracy of musical reproduction. Just a thought.....


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## Savjac (Apr 17, 2008)

Talley said:


> and I was extremely disappointed in the gladiator soundtrack... or at least the audio on the movie.
> 
> clip city


You might give it another try Mr. T, especially the CD of the soundtrack, it is one of the finest recordings of movie music I have ever heard, especially in tonality and dynamics. If you hear clipping then maybe there is something wrong in the system. I should be reproduced cleanly and occasionally very loud with instantaneous dynamics that will make you flinch. Trust me. :T


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## Talley (Dec 8, 2010)

Savjac said:


> You might give it another try Mr. T, especially the CD of the soundtrack, it is one of the finest recordings of movie music I have ever heard, especially in tonality and dynamics. If you hear clipping then maybe there is something wrong in the system. I should be reproduced cleanly and occasionally very loud with instantaneous dynamics that will make you flinch. Trust me. :T


the blu-ray many report it clips... its the audio on the disc itself. I'll have to pick up the soundtrack on CD as I bet it's pretty good.

As far as your live comment... I enjoy a few concerts here and there but I really want to start attending the Houston Symphony about 4 times a year. I prefer natural live music that isn't amplified.... but do love my rock though but my favorite is solo music. A singer playing a guitar or piano suits me just fine.


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## willis7469 (Jan 31, 2014)

I think talley was saying the gladiator mix had clipping in it. I've seen on data-bass.com(and other places) that some movies have issues with that. 
And yes jack, as a player of acoustic and electric instruments, I agree that frequent visits are necessary! 


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## Savjac (Apr 17, 2008)

willis7469 said:


> I think talley was saying the gladiator mix had clipping in it. I've seen on data-bass.com(and other places) that some movies have issues with that.
> And yes jack, as a player of acoustic and electric instruments, I agree that frequent visits are necessary!
> 
> 
> Sent from my iPhone using Tapatalk


I also play acoustic and electric instruments but I feel that I need to attend live events in order to discuss the reproduction thereof. I also love to rock out even if the recording is fiddled with in order to make thing sound better. If Y'all have not heard the Immersion Pink Floyd disc of Wish You Were Here, you need to, as it is one of the most compelling surround presentation of a great recording I have heard. 

Never the less, I do use the instruments in my home as well as some friends to tune my ears to allow me to know what things should sound like in my home. :clap:


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## willis7469 (Jan 31, 2014)

I haven't, but that immersion disk is in my list. A little OT, but I went to a concert by my sons middle school band. I took out my phone with spl app, and surprisingly found plenty of stuff in the 90db range. The funny thing is seemed more like 75. 


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## Tonto (Jun 30, 2007)

Tally wrote:



> "Your ears can never undo what is better, however, your ears are naive because they don't know what is better if you don't give them better."
> 
> Read more: http://www.hometheatershack.com/for...xpa-7-considered-upgrade-4.html#ixzz3xM1n8fvp


Back to Tennyson!


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## Talley (Dec 8, 2010)

Well the amp shipped friday... I get an email today from Emotiva saying it was shipped out w/ tracking. Was shipped late Friday. Tracking shows it arrived at the destination terminal last night at 10pm. I should be getting a call from the trucking company to accept delivery.

I can't believe they palatalize this thing and freight it. Oh well. Hoping to see what this thing finally looks like.


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## ewardjr69 (Feb 25, 2013)

The palletized my XPR -2 it was a beast to move


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## Talley (Dec 8, 2010)

ewardjr69 said:


> The palletized my XPR -2 it was a beast to move


 Which is now removed from their website.

All XPR are now officially sold out and no longer available.


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## Talley (Dec 8, 2010)

Delivering between 1-4 tomorrow. Yay half day for me haha


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## ewardjr69 (Feb 25, 2013)

Talley said:


> Which is now removed from their website. All XPR are now officially sold out and no longer available.


 I saw that at some point I'm going atmos and will need to get at least a 7 channel amp to replace my XPA -7 or add another amp all together. I'm not sure what direction emotiva is going in so I'll be patient and wait!


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## tesseract (Aug 9, 2010)

Hey, Talley. Did you think about trying XLR connections between the XMC-1 and the XPA-7? It should double the output voltage.


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## Talley (Dec 8, 2010)

tesseract said:


> Hey, Talley. Did you think about trying XLR connections between the XMC-1 and the XPA-7? It should double the output voltage.


in the works...


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## Talley (Dec 8, 2010)

:yikes: Amp is pretty heavy....

Hooked up and already listening. First impression is excellent resolution on the midbass area but the top end seems a tad "cold" is the best I can describe. The krell was definately warmer up high BUT without a doubt the krell was suffering some issues. A few key listening tests to some songs indicated to me the krell was obviously distorting. off to the repair center for it.


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## Talley (Dec 8, 2010)

what I don't like is the faint scratches indicating it had been handled. Not sure if this one was a return or what. a few spots on it. I'd expect better IMHO.


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## willis7469 (Jan 31, 2014)

Looks nice talley. Now I can say congratulations!


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## Talley (Dec 8, 2010)

Thanks!

The coldness went away... probably me firing the amp up from being cold to ship to instantly listening. after it warmed up sounds pretty good.

Good enough for me that I don't discern a difference to the Krell or at least not anything to go home about. I'm going to send the Krell off for repair so I can sell it working condition. I think it'll retain better value for me in the long run.

I will admit two things. 1. The krell was showing age 2. the XPA-7 sounds better than an aging krell. I cannot comment beyond that.

But the mid to lower bass area really picked up some resolution. The bass strings really tightened up alot.


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## Talley (Dec 8, 2010)

Another thing I REALLY REALLY REALLY want to try is changing the #4 feeder for the amp from 120V to 240V. One thing will have to be done is installing a CGB in my outlet box door and cutting the cord connector off the end of the power cable and hardwiring the end of the power cable to my #4 feeders. Then just move the neutral to a hot to a 2P breaker and boom... 240V balanced power 

I really really really want to move to an entirely 240V system... which is why I need the OPPO since it'll work on 240v. even my projector I'll wire 240v. all balanced = no transformer needed...

my voltage drop even on a 2000w load would only be .1% or about .25v = nothing. The amp could be a 7000w amp and pull 10amps at 240v adn still would only see 1.2v drop. I love giant feeder cables


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## Talley (Dec 8, 2010)

Wow... the XPA-7 is no longer on Emotiva website: https://emotiva.com/products/emotiva/amplifiers-0

looks like I got in before the last ones were sold. They are phasing out Gen2 and prepping for Gen3 I suppose.


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## ewardjr69 (Feb 25, 2013)

You received the last one! That's awesome


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## Savjac (Apr 17, 2008)

So some of us are waiting for your further thoughts on the new amp. 
How is it doing in your home ??


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## Talley (Dec 8, 2010)

Savjac said:


> So some of us are waiting for your further thoughts on the new amp.
> How is it doing in your home ??


I'm trying to see if hours makes it better. Fired up new eh... super cold sounding highs vs. the krell. I have some distortion on NOT the main channels on the krell so I can still compare two channel and the krell smokes it out the water on the parts that I can hear immediately is the cymbals on the drums. I'm demo'ing jazz music here on excellent recordings that show lots of detail.

The highs on the krell are just so warm and natural sounding and so far the coldness of the emotiva hasn't gone away but there is only about 5 hours on the amp right now. I need to turn it on and let it play for about a week stray and see if putting 100hrs helps. I'm not sure if amp burn in is true or not but some say it is but i'm still only a few hours on my xpa-7.

Without a doubt on the rear surrounds I had distortion on the krell, the emotiva proves this. Without a doubt the xpa-7 pumping 500w/ch in 2 channel mode creates some magnificent bass production. I literally hear strings vibrating in the middle of strings vibrating vs. the krell. The krell in 2 channel mode based on S&V testing only produces 150w/ch. So I've literally tripled+ my 2 channel output which is what I wanted to try. I can feel the bass... literally at a lower volume. The pounding of the kick drum went to a fast rapid thump. This is all in reference stereo mode also so the speakers are full range.

I still can't get over the highs though. The rest however is great. The whole system feels calmer but my sound stage has suffered with the xpa-7. I contribute this to a slight 60hz hum I get now with this amp which I HAVE NOT TRIED TO TACKLE YET. It's not loud... but within 3 feet of the speaker you can barely hear it.... more when you move closer. I had the krell at 99.5% silent and I really feel like this is hurting the soundstage. It's still pretty precise but it sounds like vocals have a small decoration pillow put in front of the singer.

I'm using the exact same circuit, same power cord, same everything I just literally swapped the amp out. The xpa-7 is a beast, I had to move my shelf up almost 4 inches. The xpa-7 is SO MUCH COOLER than the krell. Barely any heat coming out of the xpa-7 where the Krell was super warm/hot to the touch (120f at the vents) I'll get some hard core demo in this weekend and will leave the amp on starting tonight through saturday which will get me closer to 50+ hours on the amp so gonna see if this helps or not. Right now I still think it's too early to tell. BUT I am happy that my room is somewhat treated and my speakers are very close to being perfectly dialed in. This helps me compare. 

1000% for sure the minute I fired it up and put on my most trusted song to demo I could immediately hear cold highs vs the krell. without a doubt it sounded different BUT... .the amp had literally just came off the truck and in about 15 minutes I had it upstairs, swapped out and was listening. The temp outside was in the 50s so maybe that had a difference too.

Time will tell..... please be patient. This xpa allows me to send the Krell off to Krell for repair and then it'll be a better comparison IMHO.


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## Talley (Dec 8, 2010)

The slight ground hum is still present although I haven't done anything to try and correct this. I believe moving to a 240V circuit "should" fix this problem. I'll try that out this weekend.

On another note... I had moved my rack that is above the amp up to give about 2" clearance and notice this thing was smoking hot... literally hot to the touch so I pulled the amp out about half way but the rear is still hot. I have no choice but to cut the left side of my middle rack out completely to give enough clearance. I don't want to damage this thing by any means.


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## Savjac (Apr 17, 2008)

Talley said:


> The slight ground hum is still present although I haven't done anything to try and correct this. I believe moving to a 240V circuit "should" fix this problem. I'll try that out this weekend.
> 
> On another note... I had moved my rack that is above the amp up to give about 2" clearance and notice this thing was smoking hot... literally hot to the touch so I pulled the amp out about half way but the rear is still hot. I have no choice but to cut the left side of my middle rack out completely to give enough clearance. I don't want to damage this thing by any means.



Might I suggest that before cutting anything you try a small fan in front of or behind the amp and set it to low. I use 2 - 120mm computer fans for this and I have never had an issue subsequent to doing so. 
Actually, I have not had any issues but the amp does get warm so just in case I added the fans.


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## Talley (Dec 8, 2010)

Savjac said:


> Might I suggest that before cutting anything you try a small fan in front of or behind the amp and set it to low. I use 2 - 120mm computer fans for this and I have never had an issue subsequent to doing so.
> Actually, I have not had any issues but the amp does get warm so just in case I added the fans.


I could understand warm. The Krell is a Class A design on the input stages and runs hot, it was very warm to the touch but the temp of the case on the XPA-7 was hot... So either I need fans which I don't want to do or I need to cut out the shelf above it.

I'm more partial to just cut the shelf out, it's free and I can have it done in 20 minutes tonight.


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## Talley (Dec 8, 2010)

Savjac, you may be right. Found this: 




Would be the easiest thing to do. Place two of those on top of the XPA-7 and call it done. Not sure of the noise levels though at 22db.


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## Tonto (Jun 30, 2007)

I bought something similar to that for my x-box. Mounts right on top of the exhaust exit, usb connection, & turns on when a certain temp is senced & turns off when it drops below that. Has worked flawlessly for 2 years now. Chassis stays much cooler with it on there.


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## Savjac (Apr 17, 2008)

Talley said:


> Savjac, you may be right. Found this: Amazon.com: Coolerguys 120x25mm Rear Exhaust Blower Fan 5 Volt with USB Connector: Computers & Accessories
> 
> Would be the easiest thing to do. Place two of those on top of the XPA-7 and call it done. Not sure of the noise levels though at 22db.


I try to give good advice Mr. T. I have a fan that is housed in a metal case that sits atop the piece of electronics and it works but can make noise on occasion so I went to the double very quite fans that are powered by USB. Very quiet they are and they do a great job of moving a sufficient amount of air so as to keep my Emotiva running not much more than warm. 
I hope the fans work as well for you.


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## Talley (Dec 8, 2010)

I think I'll cut the shelf first. I want to see how this thing operates with 10" of vertical clearance above it.... THEN I'll see about adding some fans if Need be. Regardless the fan idea is a good one that I think I'll still do. Thermaltake makes a quiet usb powered 120mm fan. Two of those and I should be set.

Thanks for the assistance


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## Talley (Dec 8, 2010)

Last night I cut the middle shelf so my amp now has 10" of clearance for ventilation. Runs much cooler but there are still some hot spots above the modules in the back. I'll take this as the nature of the beast for the amp. No biggie since the Krell was hotter over a larger area.

One thing though.... and probably a deal breaker is the internal transformer hums. Hums just like some of the distribution transformers I've installed (electrician). I don't recall this when I had first turned it on but it's there and maybe I wasn't just paying attention. You can barely hear it from the MLP... its a low buzz and it's directly from the transformer which sits in front on this unit.

I've never heard any audio amplifier that had a buzzing transformer... typically when we install transformers some buzz and some do not it's just all dependent on the individual unit.

This thing is not going to last long at all in my rack....


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## Savjac (Apr 17, 2008)

Talley said:


> Last night I cut the middle shelf so my amp now has 10" of clearance for ventilation. Runs much cooler but there are still some hot spots above the modules in the back. I'll take this as the nature of the beast for the amp. No biggie since the Krell was hotter over a larger area.
> 
> One thing though.... and probably a deal breaker is the internal transformer hums. Hums just like some of the distribution transformers I've installed (electrician). I don't recall this when I had first turned it on but it's there and maybe I wasn't just paying attention. You can barely hear it from the MLP... its a low buzz and it's directly from the transformer which sits in front on this unit.
> 
> ...


You know, mine has a very slight hum as well, quietly to be sure, but it is there when I sit close. But turn on some music and nothing can be heard, even when the music is played at the lowest levels. I am not sure why its there, and I am not an expert on transformers, I supposed that due to the size of the amp and the amount of channels/watts being driven, maybe its natural. 
It has never caused me any trouble but you may wish to call Lonnie at Emotiva and ask whats up with that. I am gonna go there in a week or so, emotiva is not far from my house, to get some new Rca connectors installed and I will ask if you dont.


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## Talley (Dec 8, 2010)

Savjac said:


> You know, mine has a very slight hum as well, quietly to be sure, but it is there when I sit close. But turn on some music and nothing can be heard, even when the music is played at the lowest levels. I am not sure why its there, and I am not an expert on transformers, I supposed that due to the size of the amp and the amount of channels/watts being driven, maybe its natural.
> It has never caused me any trouble but you may wish to call Lonnie at Emotiva and ask whats up with that. I am gonna go there in a week or so, emotiva is not far from my house, to get some new Rca connectors installed and I will ask if you dont.


All transformers can make noise. More so if alot of dc current noise is trying to flow through. I don't have a vast amount of experience to audio amplifiers but my Krell is pitch silent.... no noise. My other concern is when using my Krell and it being fed from the #4 feeder circuit the speakers were dead silent but a faint faint faint hiss when ear was placed directly on the tweeter. The emotiva has introduced some noise, in one speaker the midrange is hissing slightly on the left and on the right the tweeter hisses.

My only option at this point is to switch my circuit to feed 240V for a balanced power option and see if any of this audibleness goes away. Will do that tonight. Won't take me but 5 minutes to open the panel pull the neutral and install it on a breaker to feed 240v. "Just for testing purposes" I'll run it through my 120v receptacle that way but this is only a test. If it works out then I'll hard wire my cord directly to the #4 feeder.


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## Savjac (Apr 17, 2008)

Talley said:


> All transformers can make noise. More so if alot of dc current noise is trying to flow through. I don't have a vast amount of experience to audio amplifiers but my Krell is pitch silent.... no noise. My other concern is when using my Krell and it being fed from the #4 feeder circuit the speakers were dead silent but a faint faint faint hiss when ear was placed directly on the tweeter. The emotiva has introduced some noise, in one speaker the midrange is hissing slightly on the left and on the right the tweeter hisses.
> 
> My only option at this point is to switch my circuit to feed 240V for a balanced power option and see if any of this audibleness goes away. Will do that tonight. Won't take me but 5 minutes to open the panel pull the neutral and install it on a breaker to feed 240v. "Just for testing purposes" I'll run it through my 120v receptacle that way but this is only a test. If it works out then I'll hard wire my cord directly to the #4 feeder.


LOL, wont take but 5 minutes....I think it would take me 5 days once I figured out why this would help, or if I could even do this . :dontknow:


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## Talley (Dec 8, 2010)

Savjac said:


> LOL, wont take but 5 minutes....I think it would take me 5 days once I figured out why this would help, or if I could even do this . :dontknow:


Helps I'm an electrician is all. Back to the xpa....


...This is leaning me more and more to monoblocks. I would do a stereo amp for the surrounds and three monoblocks for the front three. I'm looking at the options on this and it appears that I'm going to have to fork some $ out. September is a good time frame for me so it'll just have to wait.


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## Talley (Dec 8, 2010)

I talked briefly with my uncle and he said that it's not "unusual" for one to make noise but I should contact emotiva because it is their equipment. THEN he proceeded to tell me that it's more than likely some cheap transformer because of the price point and build of the emotiva vs other companies that are more costly that use plitron toroidals.

SO... I explained to him that my Krell has a hong kong made "Keen Ocean" transformer lol... I suppose Krell... one of the most expensive companies out there cannot afford plitron then haha.


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## Talley (Dec 8, 2010)

Well I switched over to 240V tonight... listened... nothing changed, no audible change at all. The toriodal still maintained slight hum, speakers still exhibited slight hiss.

I checked the DC offset on the amp and here were the results... not perfect but borderline. Emotiva said it could be the DC offset and mentioned to try their CMX-2 which is $100 and I'm not opposed to trying it... thinking about it. Not sure what to do they mentioned returning the XPA-7 but not like I can just buy another since they don't sell them.

Seems like the krell fix is the most logical. It's high end is definitely warmer to my ears.

See the attached for channels 1-7 for the dc volt measurements.


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## JBrax (Oct 13, 2011)

That's strange? I have the XPA-3 and it's dead silent. No audible hum whatsoever when it's on. Now if I power the system on and then turn on the amp there is an audible thump sound.


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## chashint (Jan 12, 2011)

I have followed audio forums even before Al Gore invented the internet.
Some manufacturers have an ongoing problem with transformer hum and dome have an occasional unit that slips through QC.
The occasional issue is usually fixed along eith an apology for it slipping through QC.
Unfortinately Emotivia has a long history of various problems across all product lines
If you get a good one apparently they are great.
But there's always been a significant number of hissers and hummers that are shipped.
I would find 60Hz ground loop, transformer hum, or hiss completely unacceptable whether it be a high end separates system or a simple entry level AVR system. 
Since you had a dead silent separates system before the amp swap there's only one thing it can be, and its the amp.
I don't know anything about emotivia pricing / shipping / return shipping but if the option exists to get 100% of the money back I wouldn't hesitate one second to return the boat anchor.
You have already done far more that Average Joe is capable of doing to resolve the issues.
Over time it will just get worse.
I hope you can get all of your money back.
Good luck.


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## ewardjr69 (Feb 25, 2013)

You might want to call them. I've owned an XPA-3 and currently own an XPA-5 and XPR-2 and have never heard a peep.


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## Talley (Dec 8, 2010)

ewardjr69 said:


> You might want to call them. I've owned an XPA-3 and currently own an XPA-5 and XPR-2 and have never heard a peep.


press your ear all the way against the case.... if it's silent then good.


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## Talley (Dec 8, 2010)

They recommended me buy their CMX-2 to see if that works if not they will return pay shipping and offer a refund. I think that is pretty stand up for a company to offer that.

If it works... yay... if it doesn't... Monoblocks or bust!

2 - XPA-1s for the mains
3 - XPA-1L for the surrounds

This will be my next setup if this XPA-7 doesn't work out.


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## Talley (Dec 8, 2010)

After a ton of investigating and careful pruning of my system I have found that the XPA-7 amplifier can indeed be quiet. It's toriodal is now only producing a faint hum when the ear is within 6" or closer to the front bezel/top grill openings and is of no concern anymore.

This happened by removing 240V from my AV panel and installing only 120V one leg to both busbars so that way everything is being fed from the same phase from the main panel. This is also with everything disconnected from the amplifier as well. Speakers are also 100% quiet without noise. 

However with EVERYTHING UNPLUGGED from the XMC-1 and the XMC-1 plugged into the wall and then connect the RCA cables and boom instantly a high pitch hum/buzz from the midrange/tweeter can be heard. I even isolated the RCA away from everything I could and still noise.

Tomorrow I'll go to guitar center and buy some cheap cheap XLR cables to see if the noise can be eliminated by going balanced. I still need to start plugging into devices one by one to check noise output at speaker. I WANT A SILENT SYSTEM


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## Talley (Dec 8, 2010)

Something I did made a huge.... massive improvement in my sound. I've been troubleshooting some speaker noise that appeared from the new xpa-7 and also having to deal with the transformer noise from the unit too. Unfortunately I did too much to isolate where this improvement came from but I will clue on on what I did:

1. The transformer noise was 90% eliminated when I changed my dedicated AV breaker panel from 240/120v to a straight 120v from the same phase off my main panel. It took me removing everything from the amp and unplugging everything from the wall except for the amp before I could see the improvement. Once I removed one leg off my 60a 240v breaker in my main panel and installed a jumper in my AV breaker panel to make both legs in that panel the same phase... the transformer now just barely makes a noise and have to be within 3" of the unit to hear anything and it's really really faint. SOLVED

2. I've had issues with the high frequency buzzing noise from the midrange/tweeter and I was able to isolate this to the RCA cables. I picked up two CHEAP 5' long XLR cables from guitar center and that noise is essentially removed when using those to the point there is nothing audible I'm looking into some inexpensive XLR interconnects now so if anyone has any recommendations please let me know.

I cannot move forward until I have my amp/xmc connected with balanced cables to see if any of the other equipment increases the noise. I also have the CMX-2 installed on the amplifier and pre-amp right now as well so not sure if it made any "audible" improvements however it did not eliminate any transformer hum or noise from the speakers. Only the XLR interconnects did that. Using two of the XLR cables I picked up I can listen to musice and the difference was astonishing. I'm not good at explaining it but the cymbals were so lifelike and the pinpointing of instruments were extremely precise but the biggest difference was some kind of spacious sound that made you feel like you were in the room. It's obvious that having noisy speakers cripples critical listening. The krell I got pretty quiet but unfortunately the XPA-7 seems to be very sensitive... fixing it's woes really improves the sound.


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## Savjac (Apr 17, 2008)

Talley said:


> Something I did made a huge.... massive improvement
> I cannot move forward until I have my amp/xmc connected with balanced cables to see if any of the other equipment increases the noise. Only the XLR interconnects did that. Using two of the XLR cables I picked up I can listen to musice and the difference was astonishing. I'm not good at explaining it but the cymbals were so lifelike and the pinpointing of instruments were extremely precise but the biggest difference was some kind of spacious sound that made you feel like you were in the room. It's obvious that having noisy speakers cripples critical listening. The krell I got pretty quiet but unfortunately the XPA-7 seems to be very sensitive... fixing it's woes really improves the sound.


See, cables do make a difference.


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## JBrax (Oct 13, 2011)

Uh oh, that's a long and dark tunnel!


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## Savjac (Apr 17, 2008)

JBrax said:


> Uh oh, that's a long and dark tunnel!


But it is my job Jeff, someone has to raise up the all things make a difference flag. :innocent:


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## Talley (Dec 8, 2010)

Savjac said:


> But it is my job Jeff, someone has to raise up the all things make a difference flag. :innocent:


Again... not sure exactly what made the impact since I was working on several items. Either way even in the movie "Transylvania 2" the music was clearly better than previously. Watched it last night w/ the front mains using xlr and the sides/center on rca for now. 

Also not ruling out the RCA being bad... never know.


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## JBrax (Oct 13, 2011)

Savjac said:


> But it is my job Jeff, someone has to raise up the all things make a difference flag. :innocent:


 Hahaha, understood. If the ears hear improvement whether it's real or not it's worth it, right? My take is when we start tinkering with things such as cables our system is in a good place. Electronics, speakers, amps, and so on.


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## Talley (Dec 8, 2010)

This is not some cable debate. I had noise coming from my speakers using the RCA from morrow audio that which did not produce noise with the Krell. I bought the emotiva and noise came back so I had to tear the system apart to identify the cause. XLR removed the noise from the speakers. In the process I moved the panel from 240v/120 to a sole 120v panel and I also installed the CMX-2

There is an audible improvement tons. I don't know what it was could of been either or and or all. Just stating my progress of fixing the audible noise from my speakers.


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## JBrax (Oct 13, 2011)

Wasn't trying to start a debate. Happy you fixed your noise issue.


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## Talley (Dec 8, 2010)

JBrax said:


> Wasn't trying to start a debate. Happy you fixed your noise issue.


No worries. Just one of my first taste of jumping ship across different manufacturers. Somehow some way Krell didn't make noise and the Emotiva did.... and it took different to get it back.


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