In-wall rear surround recommendations

[mossman77]

Just wanted to check in quickly. I connected one of the VTF-2 MK5s just now and ran a quick measurement using the filters from the SB-1000 (just to get an idea of what to expect). This is only one sub in the living room, same location as where the SB-1000 was. Looking very promising!

 

[William Lemmerhirt]

Looks good so far man. Do you have any sweeps without filters on the HSU?
How do you like it so far?

 

[mossman77]

Looks good so far man. Do you have any sweeps without filters on the HSU?
How do you like it so far?

I literally just connected it, so no real impressions yet, other than it sounds pretty good with this TV program that is on.

Found it odd that when running Audyssey that the tone out of the sub sounded like a full range signal, whereas with my other subs it was a low frequency thump thump.

 

[William Lemmerhirt]

I literally just connected it, so no real impressions yet, other than it sounds pretty good with this TV program that is on.

Found it odd that when running Audyssey that the tone out of the sub sounded like a full range signal, whereas with my other subs it was a low frequency thump thump.

Yeah. I don’t how audyssey can make any sense of the thumps it uses for calibration. Works though!

 

[mossman77]

Yeah. I don’t how audyssey can make any sense of the thumps it uses for calibration. Works though!

Me either. What I meant is the sub tone sounded much different with the new sub, as if it were receiving a full range signal (sounded similar to the mains but muffled), whereas my other subs were a low frequency thump.

 

[William Lemmerhirt]

Me either. What I meant is the sub tone sounded much different with the new sub, as if it were receiving a full range signal (sounded similar to the mains but muffled), whereas my other subs were a low frequency thump.

So the new sweep you put up. Was that a fresh Audyssey run, but the old minidsp filters? Or new minidsp filters too?

 

[mossman77]

So the new sweep you put up. Was that a fresh Audyssey run, but the old minidsp filters? Or new minidsp filters too?

Ahhh, that must be why. I had the SB1000 filters programmed into the DSP during the Audyssey procedure [face palm]. I was just anxious to get one hooked up. I'll spend some time this weekend to get everything set up properly (including sub#2).

 

[Pogre]

Just wanted to check in quickly. I connected one of the VTF-2 MK5s just now and ran a quick measurement using the filters from the SB-1000 (just to get an idea of what to expect). This is only one sub in the living room, same location as where the SB-1000 was. Looking very promising!

View attachment 34893

So blue is what, after? Looks very good already tho!

I think the difference you hear in the thumps between the SB and the VTF could be a combination of a wider frequency range and the extra output of being a ported sub.

 

[mossman77]

So blue is what, after? Looks very good already tho!

I think the difference you hear in the thumps between the SB and the VTF could be a combination of a wider frequency range and the extra output of being a ported sub.

The blue is simply swapping the SB1000 out with one VTF-2 MK5 (using SB1000 filters). Just wanted to quickly see what it would look like. I'll do things properly this weekend.

To clarify, both curves are sub+main response.

 

[Pogre]

The blue is simply swapping the SB1000 out with one VTF-2 MK5 (using SB1000 filters). Just wanted to quickly see what it would look like. I'll do things properly this weekend.

To clarify, both curves are sub+main response.

Well you're looking pretty damned good already! I can't wait to see what you think when you get both setup and dialed in.

 

[mossman77]

I apologize if I missed the reply, but per an earlier post I made, after making all the necessary adjustments to the subwoofers to get the best response, does it make sense to then reconnect the mains and run the EQ on the complete system? Seems to make sense to me.

Well you're looking pretty damned good already! I can't wait to see what you think when you get both setup and dialed in.

Okay. Playing around a little more this evening. I did a bunch of sweeps from 20Hz to 120Hz with both subs and got the best response with sub2 (upstairs) 180 deg out of phase. I then ran sweeps with the subs+mains with AVR xover at 60Hz, 80Hz, 90Hz, and 100Hz. The best/flatest response was with the mains xover at 100Hz. So, do I now do one more sweep with the subs only from 20Hz up to the xover frequency I chose (100Hz), apply filters, then let Audyssey do its thing, or do I leave the Mains connected and correct the curve first? Getting confused whether to program the DSP according to the entire system response or only the subs and let Audyssey take care of the subs+main integration. Seems like I'd want to apply filters to the system curve because this will be the response when everything is playing together. Guess I could try both and see what happens.

Blue curve is subs only with AVR xover at 100Hz, brown is subs+main at 80Hz, and green is subs+main at 100Hz, which is the best system response I was able to get. This is with Audyssey off, no DSP filters, and no smoothing. Speaking of which, does the smoothing actually change the calculated filters at all, or is it for display purposes only (to make the curves look nicer than they really are)?

 

[mossman77]

Crossover of 100Hz has too much localization (should have known) and Audyssey calibration made the response worse. I'll post the curve tomorrow.

 

[Pogre]

Crossover of 100Hz has too much localization (should have known) and Audyssey calibration made the response worse. I'll post the curve tomorrow.

That's why I suggested Audyssey first, then tweak with rew.

 

[mossman77]

That's why I suggested Audyssey first, then tweak with rew.

I will definitely do that and compare.

Question regarding the use of both Audyssey and REW/miniDSP: Isn't the rule of thumb to limit any boosting of signals and mostly cut/attenuate? If so, do I need to adjust REW EQ settings to ensure I am not further boosting any frequencies that have already been boosted by Audyssey?

does the smoothing actually change the calculated filters at all, or is it for display purposes only (i.e. to make the curves look nicer than they really are)?

Anyone know the answer to this?

 

[ryanosaur]

You are correct that you want to avoid boosting. It is far preferable to cut peaks rather than try to boost dips.

If I understand your last question, the smoothing of the graph is just for visual effect and ability to see things. It does not alter the measurements.

Definitely agree with Pogre that you should try Aud first, measure and correct with DSP after.

 

[mossman77]

You are correct that you want to avoid boosting. It is far preferable to cut peaks rather than try to boost dips.

Okay, that's what I thought. So it sounds like I should do a raw measurement, then run Audyssey, take another measurement to see what Audyssey boosted and avoid boosting those frequencies when I tweak with the DSP, correct?

If I understand your last question, the smoothing of the graph is just for visual effect and ability to see things. It does not alter the measurements.

Okay. I don't see the point in even doing smoothing then since it obscures the true response.

Definitely agree with Pogre that you should try Aud first, measure and correct with DSP after.

Cool.

 

[ryanosaur]

Okay. I don't see the point in even doing smoothing then since it obscures the true response.

The 1/12 smoothing makes it easier to interpret the activity. Not smoothing it, if it works for you is fine, but I know I've seen some acoustics guys ask for charts at 1/12 smoothing.

Okay, that's what I thought. So it sounds like I should do a raw measurement, then run Audyssey, take another measurement to see what Audyssey boosted and avoid boosting those frequencies when I tweak with the DSP, correct?

Some boosting is fine, and may be required... my understanding is that you don't want to rely on that because it is effectively eating the digital headroom of your amps, which in turn can lead to clipped signals sooner than would otherwise be the case. (Corrections welcome if I am missing something there.)
With the Audysseu you have, you might run into other issues across the board. I would always recommend experimenting. Try it with audyssey by itself. Listen to the full system. Make certain you are happy with the sound. (Some complain of the way Aud corrects up high.)
Anyway, you've got the tools and seem like you are on the right path.
Keep in mind that the sexiest curves aren't always the best sounding, too!

 

[mossman77]

The 1/12 smoothing makes it easier to interpret the activity. Not smoothing it, if it works for you is fine, but I know I've seen some acoustics guys ask for charts at 1/12 smoothing.


Some boosting is fine, and may be required... my understanding is that you don't want to rely on that because it is effectively eating the digital headroom of your amps, which in turn can lead to clipped signals sooner than would otherwise be the case. (Corrections welcome if I am missing something there.)
With the Audysseu you have, you might run into other issues across the board. I would always recommend experimenting. Try it with audyssey by itself. Listen to the full system. Make certain you are happy with the sound. (Some complain of the way Aud corrects up high.)
Anyway, you've got the tools and seem like you are on the right path.
Keep in mind that the sexiest curves aren't always the best sounding, too!

Makes sense. Except you'd expect there to be at least 12dB of headroom since the receiver allows me to boost the entire band by that amount, presumably without clipping. Could be wrong. Regardless, I wouldn't push things to that extent.

People that search this thread are going to be utterly confused as to how any of this has to do with surround speaker recommendations. Oh well, forums are jam-packed with digressions

 

[snakeeyes]

Makes sense. Except you'd expect there to be at least 12dB of headroom since the receiver allows me to boost the entire band by that amount, presumably without clipping. Could be wrong. Regardless, I wouldn't push things to that extent.

People that search this thread are going to be utterly confused as to how any of this has to do with surround speaker recommendations. Oh well, forums are jam-packed with digressions

Mostly just the threads with @ryanosaur
LOL. j/k

I think we are all guilty as charged....

 

[mossman77]

Should have mentioned the previous curves are with both ports plugged. I'd like a little deeper extension, so I'm going to remove one port plug for now and redo everything. Also, I'm getting some localization at higher volumes because the damn floor is vibrating. I was thinking of giving the Subdude platform a try, or maybe spiked feet.