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Discussion Starter · #1 ·
HSU subs the VTF-3.4 and 3.3

I have been instructed to use the rat-shack spl meter to set the subs at 80 dB prior to using Audyssey calibration with my receiver Onkyo-809 . However when I run Audyssey it tells me to set the sub or subs to 75 dB. If I mess with the subs volume dial to get to the 75 dB then I just defeated the purpose of the gain match.

When I have both subs on when Audyssey is saying to set 75 dB the subs are reading more like 86 dB. If I turn one of the subs off then it's reading 80 dB and that matches what I gained matched with the spl meter.

Do I need to worry about this or am I doing something wrong ?

Thanks for any info....
 

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You are trying to level match the subs. Set each sub to 72 or 73 db at the listening spot on at a time with the other sub turned off. The run the autocalibration and you should be fine. Level match is done with non-identical subs and gives the best response at the MLP.


Even with gain matching , the level of the subs have to be decreased to a workable level for autocalibration or, the calibration process will stop and tell you to turn down the subs.
 

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Dual subs = a 6dB increase in output.   So if you set them both to 80 by themselves, you will be 85-86 with them both running.  Like derrick said level match them to around 70 dB.  This should give you close to 75 with both running in order to then run audyssey.
 

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Discussion Starter · #5 ·

Quote:
Originally Posted by derrickdj1  /t/1521517/dual-subs-gain-matched-but#post_24454368


You are trying to level match the subs. Set each sub to 72 or 73 db at the listening spot on at a time with the other sub turned off. The run the autocalibration and you should be fine. Level match is done with non-identical subs and gives the best response at the MLP.


Even with gain matching , the level of the subs have to be decreased to a workable level for autocalibration or, the calibration process will stop and tell you to turn down the subs.

OK,

The HSU subs are identical subs in terms of size and power etc. The difference between them is the newer model 3.4 has more tuning options.

Do I still need to level match versus gain match ? Oh sh^t I'm getting confused again !!! Whats the difference between gain and level matching ?

As I stated I was instructed to gain match these subs from the manufacture before running Audyssey. As I ran calibration both subs combined they showed 86 dB and the calibration took with no issues.

So I have the 2-HSU subs in the front left and right corners about 14'-15' away from the MLP. I also have 2- of the lesser powerful subs Klipsch RW-12d in the back left and right corners. I thought I would get the HSU subs set correctly and then fool with the settings on the RW-12 d's later as they are closer to the MLP.

Otherwise the RW-12's are collecting dust.

Thanks
 

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Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24455425


OK,

The HSU subs are identical subs in terms of size and power etc. The difference between them is the newer model 3.4 has more tuning options.

Do I still need to level match versus gain match ? Oh sh^t I'm getting confused again !!! Whats the difference between gain and level matching ?
See this thread: http://www.avsforum.com/t/1282064/two-subs-gain-matching-vs-level-matching
Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24455425


As I stated I was instructed to gain match these subs from the manufacture before running Audyssey. As I ran calibration both subs combined they showed 86 dB and the calibration took with no issues.

So I have the 2-HSU subs in the front left and right corners about 14'-15' away from the MLP. I also have 2- of the lesser powerful subs Klipsch RW-12d in the back left and right corners. I thought I would get the HSU subs set correctly and then fool with the settings on the RW-12 d's later as they are closer to the MLP.

Otherwise the RW-12's are collecting dust.

Thanks
You don't want to run Audyssey and then add more subs afterwards. If you want to use the Klipsch subs, you want them on when running Audyssey. Gain-match the Hsu subs, (they should both be "tuned" the same), then separately gain-match the Klipsch subs. Then use the level-matching technique that Audyssey recommends to integrate all 4 subs. (Hook up the 2 Hsu subs to Sub1 output and the 2 Klipsch subs to Sub2 output.)


Craig
 

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I think what Craig is saying, run the HSU subs as one and the Klipsch subs as one unit. This will simplify the setup process. The subs are very similar and all 4 subs could be leve matched to 70 or 72 db. This may also give a more even response at the MLP. Gain match will keep from driving one sub harder than the other but, most likely will not be relevant since all these subs should have set limiters. Here is a good read on setting up the subs. A Guide to Bass Management Part I on the Bluray forum. Sorry, I am having trouble with pasting the link.
 

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Discussion Starter · #8 ·

Quote:
Originally Posted by craig john  /t/1521517/dual-subs-gain-matched-but#post_24455556


See this thread: http://www.avsforum.com/t/1282064/two-subs-gain-matching-vs-level-matching

You don't want to run Audyssey and then add more subs afterwards. If you want to use the Klipsch subs, you want them on when running Audyssey. Gain-match the Hsu subs, (they should both be "tuned" the same), then separately gain-match the Klipsch subs. Then use the level-matching technique that Audyssey recommends to integrate all 4 subs. (Hook up the 2 Hsu subs to Sub1 output and the 2 Klipsch subs to Sub2 output.)


Craig

Hey Craig,

Thanks man I'm almost there, I think ?? I have the HSU subs gain matched already and I ran Audyssey. So I need to re-run Audyssey with the Klipsch subs turned on after I gain match those two subs @ 80 db using the same method of gain matching the Hsu subs correct ? Do I put the Klipsch subs in the same original location as where the HSU subs were done in the front right corner of the room which is where one of the HSU subs sit ?

This is how HSU techs told me to gain match their subs.

To gain match, proceed as follows. Start out with your VTF-3 MK3. Play the 40 Hz test tone on our CD. Adjust the volume on the receiver to get 80 dB reading on your SPL meter (C weighting, slow, placed 3 ft in front of sub). Mark the position so you can place the VTF-3 MK4 exactly in the same spot. Move the VTF-3 MK3 out and move the VTF-3 MK4 to the same spot. Play the same track again. Adjust the volume control on the sub (not receiver) to get the same 80 dB reading. Now they are gain matched.


Also when playing the 40 HZ test tone on the HSU cd what setting/sound mode should the Onkyo 809 be set to ?

Where do I find the info on this > Then use the level-matching technique that Audyssey recommends to integrate all 4 subs ?

I have this already done > (Hook up the 2 Hsu subs to Sub1 output and the 2 Klipsch subs to Sub2 output.)

I did read some of this thread but I started going into the rabbit hole and getting off track > See this thread: http://www.avsforum.com/t/1282064/two-subs-gain-matching-vs-level-matching


Ok, thanks again for any info......
 

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Discussion Starter · #9 ·

Quote:
Originally Posted by derrickdj1  /t/1521517/dual-subs-gain-matched-but#post_24456307


I think what Craig is saying, run the HSU subs as one and the Klipsch subs as one unit. This will simplify the setup process. The subs are very similar and all 4 subs could be leve matched to 70 or 72 db. This may also give a more even response at the MLP. Gain match will keep from driving one sub harder than the other but, most likely will not be relevant since all these subs should have set limiters. Here is a good read on setting up the subs. A Guide to Bass Management Part I on the Bluray forum. Sorry, I am having trouble with pasting the link.

Ok,

Thanks for the info. I would have to agree as I did not gain match the HSU subs until I found out that one of the drivers had an issue of bottoming to fast, after trouble shooting with the HSU techs. They replaced it free of charge and I don't want to take that chance again if that was the reasoning for the driver having that issue.

As a matter of fact I just put the new driver in and have not really played anything yet.

I want to get all working today so I can watch Gravity and the new Thor tonight.
 

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Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24456325


Hey Craig,

Thanks man I'm almost there, I think ?? I have the HSU subs gain matched already and I ran Audyssey. So I need to re-run Audyssey with the Klipsch subs turned on after I gain match those two subs @ 80 db using the same method of gain matching the Hsu subs correct ? Do I put the Klipsch subs in the same original location as where the HSU subs were done in the front right corner of the room which is where one of the HSU subs sit ?

This is how HSU techs told me to gain match their subs.

To gain match, proceed as follows. Start out with your VTF-3 MK3. Play the 40 Hz test tone on our CD. Adjust the volume on the receiver to get 80 dB reading on your SPL meter (C weighting, slow, placed 3 ft in front of sub). Mark the position so you can place the VTF-3 MK4 exactly in the same spot. Move the VTF-3 MK3 out and move the VTF-3 MK4 to the same spot. Play the same track again. Adjust the volume control on the sub (not receiver) to get the same 80 dB reading. Now they are gain matched.


Also when playing the 40 HZ test tone on the HSU cd what setting/sound mode should the Onkyo 809 be set to ?

Where do I find the info on this > Then use the level-matching technique that Audyssey recommends to integrate all 4 subs ?

I have this already done > (Hook up the 2 Hsu subs to Sub1 output and the 2 Klipsch subs to Sub2 output.)

I did read some of this thread but I started going into the rabbit hole and getting off track > See this thread: http://www.avsforum.com/t/1282064/two-subs-gain-matching-vs-level-matching


Ok, thanks again for any info......
I just looked at the manual for your receiver. It has Audyssey MultEQ XT. It has 2 subwoofer outputs, but they're both the same, so you can't do the final step I suggested previously using Audyssey's level-matching technique. Therefore, here is what I would do instead:


1. Place your SPL meter at the primary listening position and each sub in it's final in-room position.

2. Start Audyssey. In the first step, Audyssey outputs a subwoofer noise signal. (It will tell you to set the subwoofer to 75 dB. Ignore that initially, (see next step.)

3. Playing one sub at a time, set each sub to 69 dB on the SPL meter.

4. Turn all the subs on and start Audyssey. If you've done Step 3 properly, your combined level for all 4 subs together should be close to 75 dB. If you're too high by more than 3 dB, redo Step 3 and set each sub to 66 instead of 69. Then redo- Step 4. Repeat as needed to get the combined output of all 4 subs to 75 dB +/- 3 dB.

5. Continue with the rest of the Audyssey run.


The above technique is "level-matching" but since you're using multiple different subs, it's probably your best option. Trying to gain-match different subs is generally not an effective technique.


To explain the difference between gain-matching and level-matching...


Gain-matching is setting the subwoofer gain controls so they are the same, irrespective of how they measure at any specific location in the room. Gain-matching ensures the subs are outputting the same acoustic energy to the room. They might measure differently in different locations in the room, but they are driving the same energy into the room. This technique ensures that the subs have equal output all the way up to thier limits, and that no one sub reaches it's limits before the other(s).


Level-matching involves picking a specific location in the room, (usually the primary listening position), and setting the gains so the subs measure equal SPL at that one location. This technique often results in all the subs having different gain settings. The sub with the highest gain setting will reach it's limits first and will set the limits for the entire system.


Craig
 

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Discussion Starter · #11 ·

Quote:
Originally Posted by craig john  /t/1521517/dual-subs-gain-matched-but#post_24458664


I just looked at the manual for your receiver. It has Audyssey MultEQ XT. It has 2 subwoofer outputs, but they're both the same, so you can't do the final step I suggested previously using Audyssey's level-matching technique. Therefore, here is what I would do instead:


1. Place your SPL meter at the primary listening position and each sub in it's final in-room position.

2. Start Audyssey. In the first step, Audyssey outputs a subwoofer noise signal. (It will tell you to set the subwoofer to 75 dB. Ignore that initially, (see next step.)

3. Playing one sub at a time, set each sub to 69 dB on the SPL meter.

4. Turn all the subs on and start Audyssey. If you've done Step 3 properly, your combined level for all 4 subs together should be close to 75 dB. If you're too high by more than 3 dB, redo Step 3 and set each sub to 66 instead of 69. Then redo- Step 4. Repeat as needed to get the combined output of all 4 subs to 75 dB +/- 3 dB.

5. Continue with the rest of the Audyssey run.


The above technique is "level-matching" but since you're using multiple different subs, it's probably your best option. Trying to gain-match different subs is generally not an effective technique.


To explain the difference between gain-matching and level-matching...


Gain-matching is setting the subwoofer gain controls so they are the same, irrespective of how they measure at any specific location in the room. Gain-matching ensures the subs are outputting the same acoustic energy to the room. They might measure differently in different locations in the room, but they are driving the same energy into the room. This technique ensures that the subs have equal output all the way up to thier limits, and that no one sub reaches it's limits before the other(s).


Level-matching involves picking a specific location in the room, (usually the primary listening position), and setting the gains so the subs measure equal SPL at that one location. This technique often results in all the subs having different gain settings. The sub with the highest gain setting will reach it's limits first and will set the limits for the entire system.


Craig

Craig,

Thanks for posting and providing solutions. I know it takes time for you to post , look up manuals, all in the good to help people such as myself. I really do appreciate that. Right now I have the 2-hsu subs split with a y- splitter cable on one of the sub outs on the receiver. So in other words the 2-hsu subs are on the same sub out from receiver and the other 2- subs are on the other sub out on the receiver.

Is that the correct way to connect the 4-subs ?


I have the older Rat-shack analog spl meter. I'm not sure I can figure out where uneven numbers would be on that spl meter such as 66 dB and 69 dB. What should I set the spl meter to ? C-weighting- slow response, dial on 70-dB or 80 db ? The spl meter starts from -10 all the way to the left, 0 in the middle and +6 to the far right, so I'm not sure how to read it to measure 66 dB as an example. Hold the spl meter at arms length, pointing straight up at ear level from the main listening seating while Audyssey outputs a subwoofer noise signal ?

Could I just use this> 2. Start Audyssey. In the first step, Audyssey outputs a subwoofer noise signal. (It will tell you to set the subwoofer to 75 dB). 3. Playing one sub at a time, set each sub to 69 dB on the SPL meter.

Could I do this for each sub one at a time and turn the volume knobs on each sub down to the 66-dB or 69 dB based on the Audyssey mic without using or instead of using the SPL meter ?

Once I'm all done with running Audyssey in all 8 positions what should the receiver subwoofer setting be 0.0dB or -10 dB etc ?


Let me know..

Thanks again....
 

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Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24459700


Craig,

Thanks for posting and providing solutions. I know it takes time for you to post , look up manuals, all in the good to help people such as myself. I really do appreciate that. Right now I have the 2-hsu subs split with a y- splitter cable on one of the sub outs on the receiver. So in other words the 2-hsu subs are on the same sub out from receiver and the other 2- subs are on the other sub out on the receiver.

Is that the correct way to connect the 4-subs ?
Yes, that is the correct connection scheme. However, prior to those connection, the 2 Hsu subs should be gain-matched with each other and the 2 Klipsch subs should be gain-matched with each other. For instructions on how to do that, see Post #5 in the thread I lined above.
Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24459700


I have the older Rat-shack analog spl meter. I'm not sure I can figure out where uneven numbers would be on that spl meter such as 66 dB and 69 dB. What should I set the spl meter to ? C-weighting- slow response, dial on 70-dB or 80 db ? The spl meter starts from -10 all the way to the left, 0 in the middle and +6 to the far right, so I'm not sure how to read it to measure 66 dB as an example. Hold the spl meter at arms length, pointing straight up at ear level from the main listening seating while Audyssey outputs a subwoofer noise signal ?
Can you mount the SPL meter on a mic stand or a camera stand? That will be much better and more repeatable than holding it in your hand. Also, you want it exactly at ear "position", not at :arm's length at ear level." You want it to be exactly in the spot between where your ears would be in the primary listening position.


If the meter is set to 70, then 70 dB is at "0" on the meter. If you want 69 dB, set the level so the meter reads -1, (70 - 1 = 69). If you want 66 dB, set the level so the meter reads -4, (70 - 4 = 66).

Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24459700


Could I just use this> 2. Start Audyssey. In the first step, Audyssey outputs a subwoofer noise signal. (It will tell you to set the subwoofer to 75 dB). 3. Playing one sub at a time, set each sub to 69 dB on the SPL meter.

Could I do this for each sub one at a time and turn the volume knobs on each sub down to the 66-dB or 69 dB based on the Audyssey mic without using or instead of using the SPL meter ?
Yes, that could work also, and is a better idea. It would, in fact, be more accurate than the SPL meter because the Audyssey mic is calibrated in this range where most SPL meters need some correction in the subwoofer range. More importantly, you would be using the same mic for setting the SPL that you would be using for the Audyssey run. Good pickup!

Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24459700


Once I'm all done with running Audyssey in all 8 positions what should the receiver subwoofer setting be 0.0dB or -10 dB etc ?
Anything within the range of adjustment of the receiver's subwoofer trim should be acceptable. However, I prefer to have a negative setting so there is some ability to raise the subwoofer level to preference. If it's at "0" or a positive number, you run the risk of overdriving the subwoofer amp inputs if you raise the subwoofer trim in the receiver.


Good luck.


Craig
 

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i have a question about dual sub setups. ive have had my pb2000s for little over a month now and love them. the way i set them up with the onkyo 818 was had both on and audyseey says to get it to 75db then i finsihed the rest of the setup. i cant remember exactly what it set the subs to i believe -8 or-7. i had the gains set to 2 on the back of the subs. so i manually raised the trim +3db hot and the sound good. sometimes i even raise it to +6 when i listen to bass heavy songs and they sound great. no chuffling choking bottoming out or that hot amplifier smell. now my question is by doing the above mentioned method of calibrating subs by having one off getting it to 70 then doing the same with the other one give me the same results just without having to muscle bass out of them? like i said they sound great and dont listen to crazy high volumes for long periods of time just movie here and there some songs. i only get to play with my toys on the weekend and at that its not very much. just want to make sure i nhave the set optimally without forcing them
 

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Discussion Starter · #14 ·

Quote:
Originally Posted by craig john  /t/1521517/dual-subs-gain-matched-but#post_24461997


Yes, that is the correct connection scheme. However, prior to those connection, the 2 Hsu subs should be gain-matched with each other and the 2 Klipsch subs should be gain-matched with each other. For instructions on how to do that, see Post #5 in the thread I lined above.

Can you mount the SPL meter on a mic stand or a camera stand? That will be much better and more repeatable than holding it in your hand. Also, you want it exactly at ear "position", not at :arm's length at ear level." You want it to be exactly in the spot between where your ears would be in the primary listening position.


If the meter is set to 70, then 70 dB is at "0" on the meter. If you want 69 dB, set the level so the meter reads -1, (70 - 1 = 69). If you want 66 dB, set the level so the meter reads -4, (70 - 4 = 66).

Yes, that could work also, and is a better idea. It would, in fact, be more accurate than the SPL meter because the Audyssey mic is calibrated in this range where most SPL meters need some correction in the subwoofer range. More importantly, you would be using the same mic for setting the SPL that you would be using for the Audyssey run. Good pickup!



Anything within the range of adjustment of the receiver's subwoofer trim should be acceptable. However, I prefer to have a negative setting so there is some ability to raise the subwoofer level to preference. If it's at "0" or a positive number, you run the risk of overdriving the subwoofer amp inputs if you raise the subwoofer trim in the receiver.


Good luck.


Craig

Great info Craig and again thanks very much.


I guess what I will do then is ditch the gain match (will have to use the subs volume to get 66 dB or so ) and the Radio Shack Analog SPL meter (the needle moves too much for exact readings) all together and just use the Audyssey mic. Use the subwoofer test tone in the 1st step of Audyssey to set each sub one at a time to around 66 dB using the sub volume knobs.

Once that has been done turn on all subs and see how close I am to the 75 dB mark with the Audyssey mic still on in the main seating area on the tripod.

After that I will run the Audyssey set up all 8-positions and then look at the sub trim level in the AVR afterwards.

I'm sure the trim level will be 0.00 or lower which is a good thing ?

If the subs are too quiet adjust to my liking ? Example if it's set to -6.5 I can adjust to let's say 0.00 which will be louder than the -6.5.

Does that sound like a good plan ?


Thanks !!!!!
 

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Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24462571


Great info Craig and again thanks very much.


I guess what I will do then is ditch the gain match (will have to use the subs volume to get 66 dB or so ) and the Radio Shack Analog SPL meter (the needle moves too much for exact readings) all together and just use the Audyssey mic. Use the subwoofer test tone in the 1st step of Audyssey to set each sub one at a time to around 66 dB using the sub volume knobs.

Once that has been done turn on all subs and see how close I am to the 75 dB mark with the Audyssey mic still on in the main seating area on the tripod.

After that I will run the Audyssey set up all 8-positions and then look at the sub trim level in the AVR afterwards.

I'm sure the trim level will be 0.00 or lower which is a good thing ?

If the subs are too quiet adjust to my liking ? Example if it's set to -6.5 I can adjust to let's say 0.00 which will be louder than the -6.5.

Does that sound like a good plan ?


Thanks !!!!!
That sounds like a great plan for your setup. You may have some gain inequalities, which *might* result in some absolute limitiations of the output, but with 4 subs, that shouldn't be a problem. Nonetheless, when your done, you may still find the bass to be too low for your liking. However, before you just turn up the sub trim, I suggest you first try adjusting the subwoofer "Distance" setting. When you have multiple subs, and they are different distances from the LP, but they're all getting the same Distance Setting, Audyssey doesn't always get that set optimally. Audyssey finds the "first arrival" of the bass signal and it assumes all the other arrivals are reflections. However, some of those arrivals are from the other subwoofers. Therefore, the optimal Distance setting could be something "longer" than the first arrival. Here is a demonstration of this phenomenon:





These two traces are the same system, which includes 3, non-co-located subs, measured from the same primary LP. The subs were all hooked to one subwoofer output, and the whole subwoofer system got one subwoofer Distance setting, just like your current system. The only difference between the two tracings is the subwoofer Distance setting in the pre/pro. With the green trace I added 4 feet to the subwoofer Distance setting. This completely eliminated a cancellation between the speakers and subs around the crossover frequency of 80 Hz. The difference in sound between these 2 graphs was incredible. The cyan graph sounded thin and weak and neutered. The green trace sounded strong and powerful and full.


So, if your bass seems too low after running Audyssey, try an adjustment of the subwoofer Distance setting before you just raise the subwoofer trim. It may solve your problem where the trim setting won't help as much, and is the wrong tool to fix the problem.


Craig
 
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Discussion Starter · #16 ·

Quote:
Originally Posted by craig john  /t/1521517/dual-subs-gain-matched-but#post_24465827


That sounds like a great plan for your setup. You may have some gain inequalities, which *might* result in some absolute limitiations of the output, but with 4 subs, that shouldn't be a problem. Nonetheless, when your done, you may still find the bass to be too low for your liking. However, before you just turn up the sub trim, I suggest you first try adjusting the subwoofer "Distance" setting. When you have multiple subs, and they are different distances from the LP, but they're all getting the same Distance Setting, Audyssey doesn't always get that set optimally. Audyssey finds the "first arrival" of the bass signal and it assumes all the other arrivals are reflections. However, some of those arrivals are from the other subwoofers. Therefore, the optimal Distance setting could be something "longer" than the first arrival. Here is a demonstration of this phenomenon:





These two traces are the same system, which includes 3, non-co-located subs, measured from the same primary LP. The subs were all hooked to one subwoofer output, and the whole subwoofer system got one subwoofer Distance setting, just like your current system. The only difference between the two tracings is the subwoofer Distance setting in the pre/pro. With the green trace I added 4 feet to the subwoofer Distance setting. This completely eliminated a cancellation between the speakers and subs around the crossover frequency of 80 Hz. The difference in sound between these 2 graphs was incredible. The cyan graph sounded thin and weak and neutered. The green trace sounded strong and powerful and full.


So, if your bass seems too low after running Audyssey, try an adjustment of the subwoofer Distance setting before you just raise the subwoofer trim. It may solve your problem where the trim setting won't help as much, and is the wrong tool to fix the problem.


Craig

OK,

Thanks for this very informative post. Unfortunately I do not own any type of measuring devices other than the SPL meter. After running Audyssey it set the front main speakers and wides to 40HZ etc. I was informed to change that to 80 HZ. So with that being said Audyssey has set the HSU subs front right and front left corners @ 17' from the main seating area. Now physically via tape measure the HSU subs are close to that distance. However the Klipsch subs are much closer around 8' or so.

To be honest Craig I really like " hard hitting bass slamming movies" and the tactical feel I get. My HT room on the 2nd floor. That is my reasoning for having 4-subs along with trying to get even smooth bass across the entire listening area. As a matter of fact I have just about all of the 5-star bass movies on the current list and a lot of the 4.5 star movies.


You see I started off with one HSU sub the VTF- 3.3 and then I purchased the cheaper Klipsch .Then I bought another HSU sub the 3.4 and then another Klipsch rw-12d. I know the HSU subs crush the Klipsch in every way , but it is what it is and I can't buy any more subs at this time. So that's why I'm trying to get all 4 subs working together.


I do plan on setting up REW and buying something like this miniDSP mic a little later. But in the meantime I will work with what I have and thanks to you, I feel like I'm finally gaining ground.

Sorry to get off track !!

OK so if I want better bass pending the Audyssey outcome where should I start with distance in the AVR settings ?


Thanks so much....
 

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With an SPL meter as your only tool, I suggest you download the Realtraps test tones: http://realtraps.com/test-cd.htm Burn them to a CD. Put the CD in your player and play the 80 Hz tone, (instructions on navigating the disc are at the bottom of the Realtraps page.) Place the SPL meter at your listening position and measure the SPL of the tone with the Audyssey Distance setting. Then add 4.5' to the subwoofer Distance. Replay the 80 Hz tone and re-measure the SPL. If it's gone up, there is benefit to be realized with subwoofer Distance adjustment. From that point, it's a matter of trial and error to find the best, most optimal setting. Just repeat the process until you find the highest SPL setting.


If the SPL doesn't change or goes down, try going the other way. Subtract 4.5' from the subwoofer distance and re-measure. Proceed as above.


Why 4.5'? Because the wavelength of an 80 Hz frequency is 14'. 1/4 wavelength is 4.5', so you're going 1/4 wavelength in either direction.


If it works, you've realized a free benefit. If it doesn't work, and Audyssey got it right, at least it didn't cost anything.


Then work on getting REW or some other measurement software up and running. It's amazing how much you can learn about your system with measurements.



Craig
 

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Discussion Starter · #18 ·

Quote:
Originally Posted by craig john  /t/1521517/dual-subs-gain-matched-but#post_24470972


With an SPL meter as your only tool, I suggest you download the Realtraps test tones: http://realtraps.com/test-cd.htm Burn them to a CD. Put the CD in your player and play the 80 Hz tone, (instructions on navigating the disc are at the bottom of the Realtraps page.) Place the SPL meter at your listening position and measure the SPL of the tone with the Audyssey Distance setting. Then add 4.5' to the subwoofer Distance. Replay the 80 Hz tone and re-measure the SPL. If it's gone up, there is benefit to be realized with subwoofer Distance adjustment. From that point, it's a matter of trial and error to find the best, most optimal setting. Just repeat the process until you find the highest SPL setting.


If the SPL doesn't change or goes down, try going the other way. Subtract 4.5' from the subwoofer distance and re-measure. Proceed as above.


Why 4.5'? Because the wavelength of an 80 Hz frequency is 14'. 1/4 wavelength is 4.5', so you're going 1/4 wavelength in either direction.


If it works, you've realized a free benefit. If it doesn't work, and Audyssey got it right, at least it didn't cost anything.


Then work on getting REW or some other measurement software up and running. It's amazing how much you can learn about your system with measurements.



Craig

Craig,

I can't thank you enough for your help. I feel good about what to try and what to proceed with now (again thanks to you). Yes sir , I'm going to get the REW very soon.

A few more questions and I will leave you alone.


I have a HSU bass cd that has a 80HZ track. Do I still need to download from realtraps ?

SPL meter on 80 dB or 75 dB when measuring and changing the distance in 4.5' increments ?

Do I need to cut all other speakers off as they are set at 80HZ ?

OK that's it ......
 

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Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24474917


Craig,

I can't thank you enough for your help. I feel good about what to try and what to proceed with now (again thanks to you). Yes sir , I'm going to get the REW very soon.

A few more questions and I will leave you alone.


I have a HSU bass cd that has a 80HZ track. Do I still need to download from realtraps ?
The Hsu track should work fine. I suggest you put your receiver in PLIIx Movie, (or Cinema) Mode. This wil re-direct the frequencies above the crossover to the CC and you'll be evaluating the subwoofer/CC blend. If you get that blend right, all the others should also be right. Then, if you want to check the L & R speakers, put the receiver in "Stereo" mode and ensure Bass Management is active in stereo. Check the left speaker/CC and the right speaker/CC blends separately.
Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24474917


Craig,SPL meter on 80 dB or 75 dB when measuring and changing the distance in 4.5' increments ?
Set it to 80. Then 0 on the meter = 80 Hz.
Quote:
Originally Posted by Ray77085  /t/1521517/dual-subs-gain-matched-but#post_24474917


Craig,Do I need to cut all other speakers off as they are set at 80HZ ?

OK that's it ......
The cancellation is caused by a negative interaction between the speakers and subs around the crossover frequency, so the speaker(s) need to be playing while taking the measurement.
 
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Discussion Starter · #20 ·
Ok Craig,

I will get to work and hope for the best. I will have more time on my hands this Sunday. Thanks again and I hope to someday have a very powerful set up like yours.
 
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