# NEWB with some questions



## Guest (Nov 16, 2008)

hello all. first things first, im brutal at spelling, so go easy on me. im looking to build a budget 2.1 set up for my house. im realy in to music, so my choices are more geared to that then HT. im looking to build a set of MTMs. ive pic out a set of Dayton DA175-8 7" Aluminum Cone Woofers, a Dayton DC28F-8 1-1/8" Silk Dome Tweeter, and a Dayton XO2W-2.5K 2-Way Crossover 2,500 Hz. the Xover are pretty nice casue u can select eather a 4 or 8 ohm woofer. i plan to use a pair of the 7" drivers in parallel for a 4ohm load. my question is. what would you recomend the volume and tuning be for the pair. Dayton recomends .5 cu per driver and tuned down low to 30Hz. this seams a bit low for a mid bass.

i have a pretty decent car audio back ground and sub woofer enclosure design. i rarely tune a sub this low, and mid bass usaly is on a HPF of 60-70Hz. so this is a whole new ball game for me! once again im looking for input on new volume and tuning for the pair, i can handle the rest from there. thanks


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## Aaron Gilbert (Nov 12, 2008)

So you say you're doing a 2.1 system? By that, can we presume you mean you'll be using these with a subwoofer? If so, there's no reason you couldn't do a sealed box. If I were given those woofers and forced to use two in a 1.0 cubic foot box, yes, I'd probably go vented just to get a little extra power handling. And tuning to 30Hz I'd probably also do, because the high Qts doesn't really make that driver all that suited to vented boxes, especially small ones. If you tune it much higher than that, you get a big hump in the low end response. In fact, I might even tune as low as 25Hz. If you are stuck on using this driver, I would at least double the box size to two cubic feet for the pair. Still tuning to 30Hz, that would give you tremendous bass. But again, if you're using a subwoofer, do you need it? If I had a choice, I wouldn't use them in the first place because of all the nasty cone breakup above 4kHz (those huge jaggy spikes in the frequency response graph). I'd prefer to use the DC160-8 Dayton woofer, which has a much smoother rolloff and takes a considerably smaller box. I'm using it successfully in a design with no low-pass at all on the woofer.


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## Guest (Nov 16, 2008)

yeah looking at the freq response graph, it does seem to get a bit hairy above 3kHz. ok scratch that then. perhaps i should stated that eventhough im looking to build a set of MTMs cabinets, i would perfer to have a tall, deep, thin box for them. and i would perfer ported. looking at the freq responce of the DC160, it does have a smoother roll off in the upper end. i was also looking at the Dayton RS150S-8 6" Reference Shielded Woofer, but it gets kinda nasty in the top end too. ok then the Dayton DC160S-8 it is. but how big and what tune??


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## Guest (Nov 16, 2008)

huh, looks like bassbox pro 6 has them in there. .75 ct ft a 32Hz looks nice. has a good flat mid range to it


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## Aaron Gilbert (Nov 12, 2008)

Bocephus said:


> ... perhaps i should stated that eventhough im looking to build a set of MTMs cabinets, i would perfer to have a tall, deep, thin box for them.
> ...





Bocephus said:


> huh, looks like bassbox pro 6 has them in there. .75 ct ft a 32Hz looks nice.
> ...


So do you mean 0.75 cubic feet total, or 0.75 cubic feet for both? If the former, I think you'd have a tough time making a tall thin cabinet with that little space, unless you block off half or more of it. For example, your width will need to be about 8". Say by tall you mean 36" (average for the type of speaker you describe). 0.75 cubic feet is 1296 cubic inches. 1296/36/8 = 4.5" deep! I don't think that's what you had in mind.  I was thinking more like 8" wide by 14" deep x 36" high. That gives you 8 * 14 * 36 = 4032 cubic inches = 2.33 cubic feet. Note these would all be internal dimensions, reduce by 1.5" in each dimension if using standard 3/4" thick walls. Anyhow, 2.33 cubic feet would give you _much_ more extended low end. Tune to 30 Hz, and you will be down only 3dB at 30Hz. Myself, with that large an enclosure, I'd probably tune to 20Hz, to keep group delay much lower in the 25Hz and up range, plus you'd get a lot more output at 20Hz (though less from 30-50Hz). 

Don't think you have to be forced into using the Dayton woofers, though. There are a lot of good woofers out there. The DC160-8 I think is one of the best values around, though, and I'm all about value. It also comes in shielded, if you want that, as the DC160S-8. That's what I'm using, but for all intents and purposes, they're the same.


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## JCD (Apr 20, 2006)

I might be missing something, but I'm assuming that you're not building from a kit.. have you already bought the drivers? If you haven't, I'd look into some of the kits that are already out there. There is a lot that goes into building a sucessful speaker, and I'm worried you won't be happy with the results after your build. In particular, using a stock crossover may not give you the results you're looking for. They don't take into the varying impedences of the speaker drivers at different frequencies.

One place I'd take a look at is zaphaudio.com. He has several moderately priced designs on this website. I'd also take a look at the kits from Madisound and Zalytron. 

Other speakers that you might look for are the Modula's and Natalie P's. Those two have had a realtively high level of support in the DIY community. Not sure what the current favorite flavor is.

Just my $0.02.

JCD


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## Aaron Gilbert (Nov 12, 2008)

I completely agree with JCD. While I think it's entirely possible to build your first speakers from scratch, picking your own drivers and crossover, it still takes a fair amount of research and reading at a minimum, to achieve a good result - though some drivers are more foolproof than others (the Dayton I'm using being one of the more foolproof). I'm using mine with a Morel MDT-12, also available at Parts Express, a great little tweeter which takes well to a simple first order crossover. 

But if one has no experience whatsoever, going with a kit all but guarantees you a great sounding speaker, at very little extra cost, if any.


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## Guest (Nov 18, 2008)

Aaron Gilbert said:


> So do you mean 0.75 cubic feet total, or 0.75 cubic feet for both? If the former, I think you'd have a tough time making a tall thin cabinet with that little space, unless you block off half or more of it. For example, your width will need to be about 8". Say by tall you mean 36" (average for the type of speaker you describe). 0.75 cubic feet is 1296 cubic inches. 1296/36/8 = 4.5" deep! I don't think that's what you had in mind.  I was thinking more like 8" wide by 14" deep x 36" high. That gives you 8 * 14 * 36 = 4032 cubic inches = 2.33 cubic feet. Note these would all be internal dimensions, reduce by 1.5" in each dimension if using standard 3/4" thick walls. Anyhow, 2.33 cubic feet would give you _much_ more extended low end. Tune to 30 Hz, and you will be down only 3dB at 30Hz. Myself, with that large an enclosure, I'd probably tune to 20Hz, to keep group delay much lower in the 25Hz and up range, plus you'd get a lot more output at 20Hz (though less from 30-50Hz).
> 
> Don't think you have to be forced into using the Dayton woofers, though. There are a lot of good woofers out there. The DC160-8 I think is one of the best values around, though, and I'm all about value. It also comes in shielded, if you want that, as the DC160S-8. That's what I'm using, but for all intents and purposes, they're the same.


ive been playing with BBP6 and external dimensions of 9X9X29 with 3/4" MDF give me .8 cu ft net, and that with 1 2.5X14.25" tuned to 32. the cabinets them self would be 43 3/4" tall, with just dead space at the bottem. i renforce the fact that ive deisgned and build many sub boxes. im not lookin for lots of low end out of these, as the subs gonna handle that. so i can see tuning anything beoyned 30, nor having a giant enclouser. i dont think im forced to use the Dayton gear, but them seam to have out standing bang for your buck!



JCD said:


> I might be missing something, but I'm assuming that you're not building from a kit.. have you already bought the drivers? If you haven't, I'd look into some of the kits that are already out there. There is a lot that goes into building a sucessful speaker, and I'm worried you won't be happy with the results after your build. In particular, using a stock crossover may not give you the results you're looking for. They don't take into the varying impedences of the speaker drivers at different frequencies.
> 
> One place I'd take a look at is zaphaudio.com. He has several moderately priced designs on this website. I'd also take a look at the kits from Madisound and Zalytron.
> 
> ...


no kit, no drivers. i dont think i could handling paying the $250 or so a kit for some box shelf MTMs when its not what i want. an i could build the whole sha bang for that cost! ive checks out zephaudio, and hes got some good kit ideas, but not what im looking for. ill look into Madisound and Zalytron later tonight



Aaron Gilbert said:


> I completely agree with JCD. While I think it's entirely possible to build your first speakers from scratch, picking your own drivers and crossover, it still takes a fair amount of research and reading at a minimum, to achieve a good result - though some drivers are more foolproof than others (the Dayton I'm using being one of the more foolproof). I'm using mine with a Morel MDT-12, also available at Parts Express, a great little tweeter which takes well to a simple first order crossover.
> 
> But if one has no experience whatsoever, going with a kit all but guarantees you a great sounding speaker, at very little extra cost, if any.



im hear to read and research. i welcome everyones input.


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## JCD (Apr 20, 2006)

Gotcha.. ~$200 for an MTM is a little tough to find, but not impossible. I don't think Madisound or Zaltron have MTM's in that price range. 

However, Parts Express has at least one kit that uses the woofer you choose -- Link. It's currently out of stock, but the price listed includes the cabinets -- you can just buy the parts though (go to the manual for a parts list). I'd think your chances at a good build would be better going with this rather than a stock crossover and trying to figure out where to set the crossover (e.g., 2500hz or 2000hz or...). Anyway, the part list is probably within your budget.

JCD


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## Guest (Nov 18, 2008)

JCD said:


> Gotcha.. ~$200 for an MTM is a little tough to find, but not impossible. I don't think Madisound or Zaltron have MTM's in that price range.
> 
> However, Parts Express has at least one kit that uses the woofer you choose -- Link. It's currently out of stock, but the price listed includes the cabinets -- you can just buy the parts though (go to the manual for a parts list). I'd think your chances at a good build would be better going with this rather than a stock crossover and trying to figure out where to set the crossover (e.g., 2500hz or 2000hz or...). Anyway, the part list is probably within your budget.
> 
> JCD


i would love to replicate this kit into my aplication. basicly find out the net air space/tunig as well as what type of Xover order etc... its says the Xover freq is at 2kHz, the only thing that suxorz is that it has a 4ohm final load. that amps im looking at, like most home audio is rated at 8ohms, and can go as low as 6ohms.


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## Guest (Nov 18, 2008)

playin around with Xover pro tonite. came up with this. all of the driver values are from the database

the one with the funky spike is actuly the 6.5" dayton classic. the other driver is the 7" aluminum cone. both use a 2nd order XOver at 2000Hz


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## Guest (Nov 18, 2008)

HMMMMMMMMMMMMMMMMMMMMMMMMMMMM http://www.zaphaudio.com/BAMTM.html
what kind amp can i get thats 4ohm stable now?? i think this just about does it for me. simple Xover to build, has ported plans. the only problem is finding an amp for this


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## Aaron Gilbert (Nov 12, 2008)

Bocephus said:


> i would love to replicate this kit into my aplication. basicly find out the net air space/tunig as well as what type of Xover order etc... its says the Xover freq is at 2kHz, the only thing that suxorz is that it has a 4ohm final load. that amps im looking at, like most home audio is rated at 8ohms, and can go as low as 6ohms.


If you're making a dual woofer speaker, you will have much greater choices of woofers if you can deal with a four ohm load. You will obtain great efficiency/sensitivity benefit by wiring the woofers in parallel. So, to maintain 6-8 ohms final, you will need to use 12 or 16 ohm woofers. These are pretty rare beasts, though not unheard of. You could use four ohm woofers and wire them in series, but you lose any efficiency benefit that way. 

There are some relatively inexpensive amplifiers and receivers which will handle a four ohm load with no problems. Which are you looking at?


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## Aaron Gilbert (Nov 12, 2008)

Bocephus said:


> HMMMMMMMMMMMMMMMMMMMMMMMMMMMM http://www.zaphaudio.com/BAMTM.html
> what kind amp can i get thats 4ohm stable now?? i think this just about does it for me. simple Xover to build, has ported plans. the only problem is finding an amp for this


That looks like a winner. Are you looking for a separate amplifier or a receiver?


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## Guest (Nov 19, 2008)

Aaron Gilbert said:


> That looks like a winner. Are you looking for a separate amplifier or a receiver?



i was looking at receivers, but i guess i may have to look at a amps. i think i realy need some advice here guys on what is best. for a great sounding budget 2.1 set up with home made MTMs. i dont have the time this eve to talk about what i need and want so, perhaps tomoro!


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## Aaron Gilbert (Nov 12, 2008)

Bocephus said:


> i was looking at receivers, but i guess i may have to look at a amps. i think i realy need some advice here guys on what is best. for a great sounding budget 2.1 set up with home made MTMs. i dont have the time this eve to talk about what i need and want so, perhaps tomoro!


Well do you have any sort of receiver or preamplifier already? You'll still need one of those to use a separate amplifier. So, purchasing a receiver that will handle four ohm speakers will usually come out less expensive than purchasing a receiver/preamp and an amplifier. There are deals to be found, especially if you are willing to go with used gear, which I feel is a great way to go for amplifiers. 

Many of the Onkyo receivers are rated to handle four ohm speakers, starting with the TX-SR705/706. If you aren't interested in home theater or multi-channel at all, there are a few inexpensive (~$300) stereo receivers which will handle four ohms, such as the Onkyo TX-8555, the Denon DRA-397, and the Yamaha RX-497. There are also cheaper versions of all those models which will also do four ohms, but have a bit less power output.

Personally, unless you plan to permanently keep this room 2.1, I'd spend the extra $100-200 and get a surround receiver which will handle four ohms. None of the inexpensive stereo receivers even have digital audio input, and only the Onkyos offer preamp output for front channels (though all have subwoofer preamp output).


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## JCD (Apr 20, 2006)

I think even going the used route, a separates path is a little too pricey for a budget 2.1 setup. I'd stick with a receiver that can handle the 4ohm load. And I agree with Aaron, going with a full blown HT receiver like the Onkyo makes the most sense to me. I would think the Onkyo 605 would work fine as well. It can be had (refurbished) for $250.

JCD


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## Aaron Gilbert (Nov 12, 2008)

JCD said:


> I think even going the used route, a separates path is a little too pricey for a budget 2.1 setup. I'd stick with a receiver that can handle the 4ohm load. And I agree with Aaron, going with a full blown HT receiver like the Onkyo makes the most sense to me. I would think the Onkyo 605 would work fine as well. It can be had (refurbished) for $250.
> 
> JCD


According to the back panel, the Onkyo 605 specifies a minimum of six ohms, which is why I said starting at 705/706. That said, the 605 may handle four ohms just fine. My last receiver, a Kenwood VR-5090, also specified a minimum of six ohms, but was perfectly happy with four ohms all around. This is where the forums come in really useful, because the manufacturers will rarely tell you that their unit will handle anything other than the factory specifications.


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## JCD (Apr 20, 2006)

Aaron Gilbert said:


> According to the back panel, the Onkyo 605 specifies a minimum of six ohms, which is why I said starting at 705/706. That said, the 605 may handle four ohms just fine. My last receiver, a Kenwood VR-5090, also specified a minimum of six ohms, but was perfectly happy with four ohms all around. This is where the forums come in really useful, because the manufacturers will rarely tell you that their unit will handle anything other than the factory specifications.


I think I'm on the same page as you now. When I went to the website, it listed watts/channel into 4ohms -- I took that to mean it could handle the load. When I go to the specifications, the 706 is the first to be "certified 4ohm performance" worthy. I think you're right, it'd probably be fine, just one of those liability issues they have to deal with.

JCD


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## Guest (Nov 20, 2008)

Aaron Gilbert said:


> Well do you have any sort of receiver or preamplifier already? You'll still need one of those to use a separate amplifier. So, purchasing a receiver that will handle four ohm speakers will usually come out less expensive than purchasing a receiver/preamp and an amplifier. There are deals to be found, especially if you are willing to go with used gear, which I feel is a great way to go for amplifiers.
> 
> Many of the Onkyo receivers are rated to handle four ohm speakers, starting with the TX-SR705/706. If you aren't interested in home theater or multi-channel at all, there are a few inexpensive (~$300) stereo receivers which will handle four ohms, such as the Onkyo TX-8555, the Denon DRA-397, and the Yamaha RX-497. There are also cheaper versions of all those models which will also do four ohms, but have a bit less power output.
> 
> Personally, unless you plan to permanently keep this room 2.1, I'd spend the extra $100-200 and get a surround receiver which will handle four ohms. None of the inexpensive stereo receivers even have digital audio input, and only the Onkyos offer preamp output for front channels (though all have subwoofer preamp output).


well, first off, i have noting. i have an older DLP HD TV, so thats its. id rater get into some HT audio b4 i upgrade the TV. also im at a bit of a cross roads between a full 5.1(im not into 7.1, at least not yet) or just 2.1. looking at my living room, it would be difficult to do a surround sound, but when the basement is finnished thats a whole other story. perhaps i should spend the money on a good 2.1 receaver (if such a monster exist) then a ok 5.1 receaver. when the basement is finished and the "home theater" goes down there, i can always upgrade



JCD said:


> I think even going the used route, a separates path is a little too pricey for a budget 2.1 setup. I'd stick with a receiver that can handle the 4ohm load. And I agree with Aaron, going with a full blown HT receiver like the Onkyo makes the most sense to me. I would think the Onkyo 605 would work fine as well. It can be had (refurbished) for $250.
> 
> JCD


i should check with my local audio shop that i deal with for my car audio. there are on of the better retialers for high end, and often have items on consignment



Aaron Gilbert said:


> According to the back panel, the Onkyo 605 specifies a minimum of six ohms, which is why I said starting at 705/706. That said, the 605 may handle four ohms just fine. My last receiver, a Kenwood VR-5090, also specified a minimum of six ohms, but was perfectly happy with four ohms all around. This is where the forums come in really useful, because the manufacturers will rarely tell you that their unit will handle anything other than the factory specifications.


ill check out the onkyo and the woods. also what brand of receaver would you guys shy away from. im looking to do this on a budget, but i dont mind spending a few bucks more a quality gear. thanks again guys, this is realy a big help


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## Guest (Nov 20, 2008)

http://www.yamaha.ca/av/PDFs/Receivers/2008_Models/HTR6130_Manual.pdf

it has a 4ohm rating (pg 66), but im unsure if its recomended to run a 4ohms i think this would fit the bill, as its afordable, and a good name


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## Aaron Gilbert (Nov 12, 2008)

Bocephus said:


> ...also im at a bit of a cross roads between a full 5.1(im not into 7.1, at least not yet) or just 2.1. looking at my living room, it would be difficult to do a surround sound, but when the basement is finnished thats a whole other story. perhaps i should spend the money on a good 2.1 receaver (if such a monster exist) then a ok 5.1 receaver. when the basement is finished and the "home theater" goes down there, i can always upgrade


There's nothing wrong with going 2.1 for now and getting a 5.1/7.1 receiver later. As I mentioned before, there are several inexpensive stereo receivers with subwoofer output (which I guess you could call 2.1 receivers) that fully support four ohm speakers. Of the ones I mentioned, I don't think I'd shy away from any of them. I myself would pick the Onkyo just for the front preamp-outputs in addition to subwoofer output, but if that's not important, any should be just fine. In my experience, Yamahas have always been a bit more reliable than Denon or Onkyo, but in general, stereo receivers tend to be _much_ more reliable to begin with. If you really want to go with a full surround receiver which supports four ohms, you may want to look into used units or reconditioned units. Lots of people have upgraded lately to get the latest and greatest HDMI or high definition this or that.



Bocephus said:


> http://www.yamaha.ca/av/PDFs/Receivers/2008_Models/HTR6130_Manual.pdf
> 
> it has a 4ohm rating (pg 66), but im unsure if its recomended to run a 4ohms i think this would fit the bill, as its afordable, and a good name


Eh, page 66? The owner's manual only goes to 64! After that you're in the appendices, which don't mention anything about speaker impedance. Moreover, on page 54, it specifies that you can use either speakers with eight ohm minimum impedance, or six ohm minimum impedance, depending on your selection in the setup menu. In the past, Yamaha surround receivers, even inexpensive ones, have typically supported continuous use of four ohm speakers in at least the front L/R channels, but this seems to not hold true at all anymore, even for many of their more expensive units.


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## JCD (Apr 20, 2006)

I think I'd avoid Harmon Kardon, Pioneer and any completely no-name brand. HK and Pio have some reliability issues from what I've read.

For all intents and purposes, I'd buy from one of the following three brands:

Denon
Yamaha
Onkyo

JCD


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## Guest (Nov 23, 2008)

ahhhhhh, i think im just gonna build a sweet set of TM towers. or maybe TMW towers


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## JCD (Apr 20, 2006)

I feel your pain.. tough to find the right combo at reasonable prices.

In any case, I look forward to your build.

JCD


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## Guest (Nov 24, 2008)

JCD said:


> I feel your pain.. tough to find the right combo at reasonable prices.
> 
> In any case, I look forward to your build.
> 
> JCD



you said it. i think i may do zaph SR 71, and add a woofer later. ill model the sub accordingly and build the TMW towers, with a serperat chaimber, and add the sub/port/amp later. and u can bet ill post the build log up


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## JCD (Apr 20, 2006)

Looks good to me! I've actually looked at that design for a friend of mine. I decided to try to build something from scratch, but that probably would have been my first kit choice given his budget.

When you add the woofer, how are you going to direct a signal to it? Will you redesign the crossover?

JCD


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## Guest (Nov 28, 2008)

JCD said:


> Looks good to me! I've actually looked at that design for a friend of mine. I decided to try to build something from scratch, but that probably would have been my first kit choice given his budget.
> 
> When you add the woofer, how are you going to direct a signal to it? Will you redesign the crossover?
> 
> JCD


seperate chaimber and its own plate amp


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