Small vs Large & Passive vs Active

[AcuDefTechGuy]

It seems like most people recommend setting the speakers to Small when using subwoofers.

I see the logic to that since most speakers cannot go down to 20Hz flat.

But what about speakers like the Revel Salon 2 or the KEF 207/2 that can go down to 20Hz FLAT IN-ROOM RESPONSE (Stereophile John Atkinson's Room)?

Salon 2:

KEF 207/2:

So Question #1 is:

Would you still set the Speakers to Small and the Crossover to 40Hz (this is the lowest crossover setting allowed on the Denon AVP-A1HDCI)?

Another question is the Passive vs Active Subwoofers, like the RBH Sound 1010-SEN/R (20Hz @ -3dB) vs 1010-SEP/R (18Hz @ -3dB) and the 1010-SEN (24Hz @-3dB) vs 1010-SEP (20Hz @ -3dB).

If you use the Passive subwoofer 1010-SEN/R, you have to use your own amplifier (instead of the 350-watt amp that came with the 1010-SEP/R).

So Question #2 is:

If you increase the Subwoofer Level in the Pre-pro by +2dB, +3dB, +4dB, etc., would you achieve that same 18Hz @ -3dB?

 

[templemaners]

I think part of it would depend on how capable my subwoofers are - sure, my speakers can go down to 20 Hz, but do they do it as well as my subwoofer? I'd imagine anyone who can buy ~$20K speakers has something slightly above the quality of a $500 subwoofer.

Why not set it at 40 Hz and see what sort of measurements you get in your room. With all due respect, unless John Atkinson is giving me his room to use, his in room measurements are only useful for identifying which speakers are the most accurate. It doesn't take into account how my room will interact with said speakers.

So, I say try it, measure the results, and then compare to other data points (running full range, running with a sub at crossover points of 60, 80, 100, 120) to see what sounds best to you.

 

[Hocky]

My main speakers are -3db @ 20hz in my room at high db with no issue. I played a lot with a 40hz crossover vs full range and honestly, there was not a notable difference either way. Because of that, I stuck with the 40hz crossover - might as well keep the stress off of the mains if it doesn't make a difference. Of course, if you dial your sub in too hot, you'll probably have weird response with the 40hz xover vs full range because of the +xdb jump due to your sub. In this case, you'd probably prefer to run them full range.

 

[InTheIndustry]

I think part of it would depend on how capable my subwoofers are - sure, my speakers can go down to 20 Hz, but do they do it as well as my subwoofer? I'd imagine anyone who can buy ~$20K speakers has something slightly above the quality of a $500 subwoofer.

Why not set it at 40 Hz and see what sort of measurements you get in your room. With all due respect, unless John Atkinson is giving me his room to use, his in room measurements are only useful for identifying which speakers are the most accurate. It doesn't take into account how my room will interact with said speakers.

So, I say try it, measure the results, and then compare to other data points (running full range, running with a sub at crossover points of 60, 80, 100, 120) to see what sounds best to you.

My main speakers are -3db @ 20hz in my room at high db with no issue. I played a lot with a 40hz crossover vs full range and honestly, there was not a notable difference either way. Because of that, I stuck with the 40hz crossover - might as well keep the stress off of the mains if it doesn't make a difference. Of course, if you dial your sub in too hot, you'll probably have weird response with the 40hz xover vs full range because of the +xdb jump due to your sub. In this case, you'd probably prefer to run them full range.

What speakers do you guys have?

 

[templemaners]

What speakers do you guys have?

In my office on my cheap 2 channel system, I have Behringer 2030P's and a HSU STF-1.

For my living room, if I can ever stomach coughing up enough $$$ to get the receiver I want, I have Ascend Acoustics Sierra 1's for the front soundstage and Infinity P362 for surrounds, ready to go.

My statement was not to imply that I have 20 Hz capable speakers - it was to say if I had something like Salon 2's or Kef 207/2's, it would still depend on my subwoofer(s) quality/performance level for me to figure out the best crossover point.

 

[Vaughan Odendaa]

Bass content exists in the main channels that reach down lower than 20 Hz (some down to 15 Hz and fewer still below that). Which means those big Revels still won't cut the mustard. Even if their response was down to 20 Hz it most likely wouldn't be perceived and I have a feeling they simply won't provide adequate displacement down to 20 Hz for it to be worthwhile.

Secondly, the best positioning for low bass response is usually not the same for imaging, so I think either way, the Salons will be at a disadvantage. High-pass them at 40 Hz, the chances are they will sound cleaner and less congested and the power requirements will be significantly reduced which provides even further benefits.

 

[Hocky]

What speakers do you guys have?

ML summit.

 

[InTheIndustry]

Bass content exists in the main channels that reach down lower than 20 Hz (some down to 15 Hz and fewer still below that).

Could you provide a link to info on this? I will be interested to read more.

Thanks!

 

[Vaughan Odendaa]

Here you go : http://www.avsforum.com/avs-vb/showthread.php?t=1288162&highlight=bass+management

 

[AcuDefTechGuy]

Here you go : http://www.avsforum.com/avs-vb/showthread.php?t=1288162&highlight=bass+management

So that is the "redirected bass" - the bass from the main front Left & Right channels that would be redirected to the subwoofer?

So that is saying the "Incredible Hulk" had a peak maint front Left & Right bass level of 9Hz @ -10dB Volume?

No wonder I love that movie.

 

[TLS Guy]

By the look of it, neither the Revel, or the KEF speaker need a sub except for HT.

I would set the the speakers to large and have a sub reserved only for the LFE channel. For music I would not use a sub.

There is nothing to compare with a true full range speaker.

Because of the design of my system, I am able to mix the LFE channel to four of the drivers.

I have absolutely no need of a sub.

Any sub that was not a huge TL with a response below 20 Hz would be an absolute quality spoiler.

My speakers in room are 3db down at 20 Hz, but with second order roll off, so there is output below 20 Hz.

With all the effort put into those speakers, rolling them off in the low end is tantamount to a criminal act.

Suds are for puny speakers that can't cut the mustard.

 

[GranteedEV]

I understand where TLS Guy comes from on his position but one thing that full range speakers can't do is address bass room modes as well as the multiple mono subs approach. It's the nature of rooms to have suckouts which you just can't fix with EQ, and absorption does not work well that low. By having multiple subs, placed at random but notably different locations (IE side cieling + back wall center + side wall corner + front wall side?) you can then EQ (FIR) flat frequency response. At bass frequencies, the frequency domain dominates so there's no need for imaging or worrying about late reflections as long as your sub is well designed. If you have a room that absorbs low frequencies from 100hz to 350hz or so, reflective with frequencies above that, and multiple subs to smooth response below 100hz, I think you have potential for very good sound - not strictly speaking output. Getting the system integrated properly is still a task that should not be underestimated I'm sure.

Now a full range speaker with cardioid bass.. that might be an option..

http://www.wvier.de/texte/Beneficial of Coupling.pdf

Which is why when I have to money for building that Nao Note, I will build it with the U-Frame woofers, for the semi-cardoid behaviour.

 

[Pyrrho]

It seems like most people recommend setting the speakers to Small when using subwoofers.

I see the logic to that since most speakers cannot go down to 20Hz flat.

But what about speakers like the Revel Salon 2 or the KEF 207/2 that can go down to 20Hz FLAT IN-ROOM RESPONSE (Stereophile John Atkinson's Room)?

...

So Question #1 is:

Would you still set the Speakers to Small and the Crossover to 40Hz (this is the lowest crossover setting allowed on the Denon AVP-A1HDCI)?

Another question is the Passive vs Active Subwoofers, like the RBH Sound 1010-SEN/R (20Hz @ -3dB) vs 1010-SEP/R (18Hz @ -3dB) and the 1010-SEN (24Hz @-3dB) vs 1010-SEP (20Hz @ -3dB).

If you use the Passive subwoofer 1010-SEN/R, you have to use your own amplifier (instead of the 350-watt amp that came with the 1010-SEP/R).

So Question #2 is:

If you increase the Subwoofer Level in the Pre-pro by +2dB, +3dB, +4dB, etc., would you achieve that same 18Hz @ -3dB?

For the first question, as templemaners has already stated, it depends upon the relative abilities of the subwoofer and the main speakers. If one has subwoofers capable of 10Hz, why would you want to miss out on that deep bass by sending it to the main speakers that are flat only down to 20Hz? Do you want to miss out on the deepest frequencies of a pipe organ, or do you want it reproduced closer to all of its intended glory?


For the second question, what unpowered subwoofers are capable of will in part be dependent upon the amplifier used with them. Assuming a flat bass response and sufficient power to drive them, one will be able to get all that the subwoofers are capable of delivering. One sets it up just the same as one sets up powered subwoofers, with the preamp subwoofer output going to the input of the amplifier driving the subwoofers, but one also has to hook up speaker wire from the amplifier to the unpowered subwoofers. One sets the level exactly as one would normally set it with a powered subwoofer. And then if one increases the subwoofer level from there in the preamp, it will have precisely the same effect as it would have with a powered subwoofer. After all, what one is doing is simply having the gear in one more box than if one were using a powered subwoofer.

I personally like using unpowered subwoofers (I have a pair of the old SVS CS-Ultra subwoofers). I like this because with subwoofers, amplifier failure seems more common than woofer failure, and one can easily replace an external amplifier. Also, having the amplifier in a separate box allows one to have it in open air all around for better heat dissipation, which should improve reliability. And one can select whatever amplifier one wants, of whatever quality or price one sees fit, so one has greater flexibility with it. It also makes the subwoofers a little less heavy and slightly smaller (for the same internal volume), which is nice when moving one.

Of course, neither one will inherently sound better; it is simply a decision on where to put the amplifier, whether to build it into the subwoofer or have it in a separate box.

 

[AcuDefTechGuy]

5.0 & LFE redirection

Okay, theoretically, let's say you have 5 speakers that can go down to 10Hz @ -10dB in room response. Theoretically.

If you set the pre-pro to NO SUBWOOFER and all speakers to LARGE, will the LFE channel be redirected to ALL FIVE LARGE speakers, or just the front LEFT & RIGHT?

What is the bass management algorithm?

So I called 2 different Denon Tech Support guys.

The first Tech said that the LFE would be redirected evenly and equally to all five large speakers.

The second Tech said the LFE would be redirected "mainly" to the front Left & Right, "secondly" to the Center, and "thirdly" to the Surround speakers.