# Anyone use REW to measure Onkyo 805?



## lovingdvd (Jan 23, 2007)

I currently have a Yamaha HTR-6090. Unfortunately I have to use it in "Straight" mode because ALL of the other Yamaha enhanced modes (even its basic surround sound modes) add boosts in the 30-80hz range for the fronts - even if the fronts are set to cross over at 80hz!!

For instance, if I set my fronts to xo at 80hz, and then use one of those modes, the fronts will still put out a LOT of db above 80hz. Yes I am aware that it is not a cliff at 80hz and because of the curve you should still get SOME freq below the xo point from the fronts. However I was getting db well above what the xo line is in any of these modes. Switching to straight made it so that the bass sent to the subs followed the xo curve line much more as expected.

I also had this same issue with my Yamaha RX-V1400 which I had before the 6090...

At any rate, I am getting ready to switch receivers and thinking serious about the Onkyo 805. I am VERY CURIOUS to know if I can use some of the basic processing modes in the 805 such as THX Cinema etc without having it screw with the bass like my Yamaha does.

Has anyone done any measurements with REW and noted what impact the various modes of the 805 have on the bass. Might I finally be able to use these modes without it messing up my bass if I go up to the Onkyo 805?

Thanks!


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## brucek (Apr 11, 2006)

I'm going to move this to Home Theater Components forum. I think you'll have better luck there. 

brucek


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## Sonnie (Apr 11, 2006)

I have a sneaky suspicion that no one has probably tested this... probably no one is suspecting it does anything. It would be interesting to see some testing done though.

I remember Audyssey EQ was effecting my bass response below my 80Hz crossover so I don't use it, but what the Yamaha receiver is doing is a bit different.


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## lovingdvd (Jan 23, 2007)

Sonnie said:


> I have a sneaky suspicion that no one has probably tested this... probably no one is suspecting it does anything. It would be interesting to see some testing done though.
> 
> I remember Audyssey EQ was effecting my bass response below my 80Hz crossover so I don't use it, but what the Yamaha receiver is doing is a bit different.


Thanks Sonnie. I was wondering how much Audyssey EQ would help in terms of smoothing over the sub woofer, I was hoping it would do a nice job and make me less dependent on REW and manual configuration of filters, but from your post it seems not... ?


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## Sonnie (Apr 11, 2006)

It could help... you would just need to measure the before and after to see. I was and still do use the BFD to equalize the subs. Here is a thread with my findings.


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## RollsRoyce (Apr 20, 2006)

I just got a 705, the 805's kid brother. Although it's less powerful, it has the same Audyssey MultiEQ XT (up to 8 measurement positions) as the 805. When I ran the Audyssey setup, I did so with my BFD in bypass mode so it wouldn't undo any of my BFD settings, and so I could see how it did without the BFD's help. The results were very good, with a smooth bass response that sounded not unlike my results with REW, the BFD, and my previous Pioneer receiver with Advanced MCACC. After a week or so of listening, I decided to fire up REW and see why it sounded so good. To my surprise, the graph very closely followed the target line of the selected cutoff plus my chosen house curve of a 7 dB rise at 30Hz, with the exception of a falloff in response below 25Hz. This was with the BFD bypassed. I put the BFD back in the circuit and set it for a slight boost at about 22Hz to reclaim some of the lost very low end. Mind you, I was very happy with the sound of the Audyssey sub corrections prior to running REW, and really ran REW more out of curiosity than anything else.

Short version is that I think the Audyssey system works really well and delivers low-frequency results not unlike those that can be achieved with REW and a BFD. It brings out detail (not hiss or harshness) at all frequencies for both movies and music. I'm really glad the 705 has it!:T


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## Hakka (Sep 10, 2006)

I've been reading a bit about Audyssey EQ on the new Onkyos and it seems there are some problems with it cutting off the sub channel at around 20hz, this only affects those of us with subs that reach down this low obviously. I'm not sure if this is unique to the new onkyos or if its all Audyssey AVRs, I read it in the Onkyo thread at AVS.

Hakka.


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## RollsRoyce (Apr 20, 2006)

I don't know that it's a matter of Audyssey cutting off the sub channel as much as that it's adjustment floor seems to be 25Hz. At least, that's the lowest filter available if you want to do manual EQ on my 705. It's hard to say if it's an issue with Audyssey itself or with Onkyo's implementation of it. For instance, Onkyo gives users no manual control over the different response curves programmed into MultiXT, although other manufacturers do. It does automatically switch curves when the receiver is placed into or out of a THX listening mode, from what I've read on other forums. I do remember reading that there were bass cutoff issues with early implementations of MultiXT, but that they were addressed with firmware upgrades for older units and corrected on the production line for newer ones.


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## HionHiFi (Feb 18, 2007)

I own a Denon 3808ci receiver with Audyssey MultiEq XT and yes it does work wonders. Take with a grain of salt mind you. If you haven't taken care to setup your speakers up correctly, Audyssey will less of an minimal impact. Done right though it's a very nice system to have. 

The Audyssey does not cut subwoofer frequencies off below 20hz. Rather it doesn't filter or operate below that frequency. The information is still played, jut not with Audyssey doing anything to the signal.


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## Hakka (Sep 10, 2006)

There have been numerous reports from 875/805 owners in Australia that have measured reduced sub 20hz bass response when Audyssey is activated, using REW and/or RTA software. It seems like there is an issue with Onkyo's implementation, It seems other brands don't have this problem. 


Hakka.


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## HionHiFi (Feb 18, 2007)

> Hakka
> There have been numerous reports from 875/805 owners in Australia that have measured reduced sub 20hz bass response when Audyssey is activated, using REW and/or RTA software. It seems like there is an issue with Onkyo's implementation, It seems other brands don't have this problem.


I wonder if this problem is global Audyssey problem or just with the Onkyo's implementation of the system?


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## Hakka (Sep 10, 2006)

Are you able to take some REW measurements of the 3808 with the Audyssey on and off. You don't necessarily need a sub that can play sub 20hz, just measure the sub pre out of the 3808. I would be very interested to see the results.

Hakka.


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## sfdoddsy (Oct 18, 2007)

I have an actively tri-amped system using digital crossovers (DCX2496) which allows me to apply room EQ, plus a sub which is EQed with a BFD, plus I use the Onkyo SR705 as a prepro.

I did a comparison between my EQed system with and without Audyssey overlaid, measured with TrueRTA.

Audyssey does indeed roll off the bass compared to my preferred settings, which tilt up towards 20Hz. It also rolls off the highs.

It does, however, perform much the same kind of correction on individual frequencies as we do with the BFD, so the bass was very flat. Too flat for my tastes.

Since I have more EQ options than I can shake a mic at I don't use Audyssey, but for most people it would be a very good thing to have. If you have a sub with a Linkwitz transform or some similar global to apply post-Audyssey that would be perfect.


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