a couple questions on dual vtf-15h set up

[SteveO]

Is it better to leave the subs gain matched when they are located in opposite corners or would it be better to have them level matched from the seating position? I have one in the front right and the other in the back left, I'm sitting much closer to the sub in the back.

A seperate question I have has to do with setting up the receiver. I have a yamaha rxv-663 and it seems like it doesnt give me any bass when I do the auto calibration. If I have both subs at around 9 it it will set the sub output at -10 and it seems to have no bass at all. If I bring it up to 0 it gets some bass but nothing close to what I want. I tried running auto with just one sub at 9 and it sets it at -6 and after turning on the second sub I have to crank the volume very high to get any bass.
I ended up setting the volume on the subs to the next line up at around 10:30 and setting the receiver sub output to 0 to get decent pounding from the subs.
I did check to make sure all speakers are set to small after each auto run.

I guess my question is am I doing something wrong or is this a common issue with yamaha? I spent alot of time messing with this and it still doesnt sound right.
Thanks

[Tom C]

There are others that can speak to this better than I, but my guess would be that the 9 o'clock position is too high. You want the sub level at about +/- 3 in the receiver. What I would do is to run your auto setup with one sub. Adjust the gain (volume) switch on the back of your sub till you get close to 0. Since you have two, I would shoot for +3. Then do the same for the other sub. After that run auto setup with both subs on. Hopefully it'll be some where around -3.

When your sub is louder the receiver will try to compensate by going lower. If it's low then it'll raise the sub channel to compensate.

As far as your original question about level vs gain I don't know about that since I only have one.

If you haven't already, try posting on AVS in the VTF-15H thread for additional help.

http://www.avsforum.com/t/1288202/th...5h-thread/4710

Sorry I can't help more.

[SteveO]

Originally Posted by Tom C

There are others that can speak to this better than I, but my guess would be that the 9 o'clock position is too high. You want the sub level at about +/- 3 in the receiver. What I would do is to run your auto setup with one sub. Adjust the gain (volume) switch on the back of your sub till you get close to 0. Since you have two, I would shoot for +3. Then do the same for the other sub. After that run auto setup with both subs on. Hopefully it'll be some where around -3.

When your sub is louder the receiver will try to compensate by going lower. If it's low then it'll raise the sub channel to compensate.

As far as your original question about level vs gain I don't know about that since I only have one.

If you haven't already, try posting on AVS in the VTF-15H thread for additional help.

http://www.avsforum.com/t/1288202/th...5h-thread/4710

Sorry I can't help more.

Thanks for the reply. I might have to check out the avs forum you mentioned.
It just seems odd that having the subs set at 9 and manualy raising the sub volume on the receiver to 0 from the -6 is not providing much bass. I dont understand how lowering the subs volume so the receivers auto run sets it at 0 will give more bass?

[Tom C]

Originally Posted by SteveO

Thanks for the reply. I might have to check out the avs forum you mentioned.
It just seems odd that having the subs set at 9 and manualy raising the sub volume on the receiver to 0 from the -6 is not providing much bass. I dont understand how lowering the subs volume so the receivers auto run sets it at 0 will give more bass?

When you say that it's not providing much bass are you talking about during auto cal and when listening to DVD, CD, etc., or just when listening to DVD, CD, etc?

If not at all, check your receiver setup menu. It might be set to no subs or something like that. If it's missing only during play back of movies, etc., try something from this list:
http://www.avsforum.com/t/1333462/th...equency-charts

When you run auto cal it adjusts the level of each channel so that they will be all be equal. The range can vary, but most receivers are something like +/- 10 or 12. You want it close to the middle of the range.

The 9 o'clock position on the back of the sub is a starting point. If your receiver sets the sub channel -10 (which I'm guessing is the lowest it can go) that means the sub is too loud. You then have to lower the sub at the sub and rerun auto cal. Repeat as necessary to get the level around zero.

If none of this helps then you may want to call Hsu (1-800-554-0150). Sounds like something else is going on.

[lradden]

Originally Posted by SteveO

Thanks for the reply. I might have to check out the avs forum you mentioned.
It just seems odd that having the subs set at 9 and manualy raising the sub volume on the receiver to 0 from the -6 is not providing much bass. I dont understand how lowering the subs volume so the receivers auto run sets it at 0 will give more bass?

Any chance your sitting in a null? If you're in a null then raising from -6 to 0 still won't help much.

[SteveO]

I get good bass if I turn up the sub volume after running the auto calibration on the receiver.
The last time I did it with only one sub at 9 then ended up with -6 on the receiver, so even after turning on the second sub I still got very little bass and turning the receiver up to 0 I still wasnt getting much bass, didnt matter if it was movies or music I had the receiver volume cranked up high... so I turned up the subs volume to around 10:30 and gain matched them and left the receiver sub volume at 0 and now get good bass.
I have read on here and avs forums that we shouldnt mess with the sub volume after doing the auto calibration but my receiver seems to be way off on the bass managment department.

[SME]

It's usually better to gain match, not level match multiple subs. Otherwise, the maximum clean output of the system will be limited by the sub that has the higher gain setting. Be sure to gain match before any auto-setup, if you use it.

I may be wrong, but I recall reading that Yamaha's auto setup is unreliable with subwoofers. Is it possible to disable calibration for just the subwoofers in the auto setup of your receiver? Since you said you did gain matching, I assume you have an SPL meter. You can use the SPL meter to calibrate the sub level manually.

[SME]

I just read your note about a sub in each corner and that you are sitting much closer to one of them. How far away are you from each sub? If the distances differ by a lot, they may be difficult (but not necessarily impossible) to integrate properly.

[pmr]

Originally Posted by SteveO

Is it better to leave the subs gain matched when they are located in opposite corners or would it be better to have them level matched from the seating position? I have one in the front right and the other in the back left, I'm sitting much closer to the sub in the back.

A seperate question I have has to do with setting up the receiver. I have a yamaha rxv-663 and it seems like it doesnt give me any bass when I do the auto calibration. If I have both subs at around 9 it it will set the sub output at -10 and it seems to have no bass at all. If I bring it up to 0 it gets some bass but nothing close to what I want. I tried running auto with just one sub at 9 and it sets it at -6 and after turning on the second sub I have to crank the volume very high to get any bass.
I ended up setting the volume on the subs to the next line up at around 10:30 and setting the receiver sub output to 0 to get decent pounding from the subs.
I did check to make sure all speakers are set to small after each auto run.

I guess my question is am I doing something wrong or is this a common issue with yamaha? I spent alot of time messing with this and it still doesnt sound right.
Thanks

If you are sitting closer to one of the subs its better to level match.

Get a SPL meter and set the gain on each sub to measure approx. 72 db at your MLP. Together they should then equal approx. 75 db. at the MLP. Then run your auto eq.

Of course if your MLP is in a bass null, all of this is moot. The only way to properly integrate subs is to run frequency sweeps to see whats actually going on. Get a calibrated mic and download REW. Otherwise youre just spinning your wheels...

[SteveO]

Thanks for the help everyone.

SME, I can disable the sub option so I might try doing more auto runs with and without the subs, and the sitting position is 15' from the front right sub and 5' from the left back sub, at times I can hear that the back sub is there.

I received the subs last thursday and spent most of the weekend messing around with different locations for them and unfortunitly the best place for sound (front right corner and front under tv) dosent work with the wife, so this is the next best sounding location that she will accept.
I dont think I'm sitting in a null becouse it sounds/pounds good other than locating the back sub.

When I gain matched the subs I used the 50hz on the cd hsu sent, if I do try and level match the subs from the seating position do I also use the 50hz?

[SME]

Definitely try excluding the subs from the calibration, but do note that a distance difference of 10 feet is a lot! Integrating them well may bet quite difficult. I strongly agree with pmr that taking measurements with at least an SPL meter is a good idea! If you don't have the patience for this, the best thing to do may be to move both subs into the same corner, assuming space allows.

With that said, I strongly disagree with pmr about level matching them. Not only will it reduce headroom, but I think it will also likely accentuate the interference problems caused by their distances being so different. In my opinion, a better approach would be to gain match them and then enable the crossover and reduce the frequency cut off until it doesn't cause interference with the other sub anymore. My suggestion would be to try enabling the crossover on the distant sub first; however, doing this on the closer sub instead could help with making it less localizable. If you're up for it, try out both ways.

If you are real determined, you might consider buying a digital processor that lets you set individual delays for the signal to each sub. Some of these also feature EQ, which you could use to further optimize the blend instead of only relying on the crossover. if you go this route, you'll also want to invest in a measurement mic so you can test different configurations more quickly.

[pg_rider]

After running your auto-cal did you go into the menus and verify that all speakers were set to small with at least an 80Hz (or higher) crossover? If not you need to do that...

[SteveO]

I do check the speaker size after auto run, sometimes it has it as small and others at large, then I change to small. I have Boston acoustic bookshelf type speakers rated for 60hz. It always has the crossover at 80.

I think the receiver is haveing issues with the bass manegment. I played around with the subs off to see how low the other speakers go by using the test cd from hsu and spl meter and I discoverd that it dosent matter where the crossover is set on the receiver it still puts out low frequency. For example I set it as high as it go's to 200 and still a get strong reading at 50hz. I know there's going to be a roll off slightly below where its set at but this is still full strength.
Even at 20hz I still a small reading and can feel the woofer moving.

The dual 15h's set me back alittle so a new receiver isnt in the budget now, but after many hours messing with it it dosent sound too bad.

Thanks again for the suggestions. I will admit that some of the stuff mentioned is over my head, such as digital processor, measurement mic, and frequency sweeps. I'll have to do some research.