Sanity check: Bad Sub ? (REW Sweep results)

[shadyJ]

The measured response is largely the room. The sub probably measures OK. The dip in the response at is probably the distance difference from the port to the woofer, or maybe the port is over-represented. If you want to be sure, do a near-field measurement of the port (like 1 or 2 inches) and then a near-field of the woofer. That should at least tell you if one of them is misbehaving.

 

[lovinthehd]

The measured response is largely the room. The sub probably measures OK. The dip in the response at is probably the distance difference from the port to the woofer, or maybe the port is over-represented. If you want to be sure, do a near-field measurement of the port (like 1 or 2 inches) and then a near-field of the woofer. That should at least tell you if one of them is misbehaving.

Did you measure that sub? Gotta link?

 

[Linwood]

So you moved the better speakers to the front of the cabinet to avoid reflections?

The new speakers' fronts are slightly in front of the cabinet, and at the outer edge of the wall. They are 10.5" off the back wall, KEF says something like 9" minimum, and recommended I stuff the port with their provided paper muffle (which I did). The new sub is about the same width as the old so should fit i the same spot, but unlike the old which is downfacing will face outward, so won't be in a cave of sorts from the furniture.

The center is right at the front edge of the glass top.

I may try putting the sub outside the towers, which would look better, but the seating in the area is at or somewhat outside where they towers are now, so that would make the sound at the outside seats worse, I think, if they are put in closer. As it is, they are a bit of a road hazard of someone going around those corners.

In this shot the console is probably 4" further forward than I hope to get it, I've got some balled up sub cable (it's like 30' and really heavy) that I need to fix by buying a new coax cable, which this is a good reminder of, thanks.

Advice welcomed.

 

[everettT]

The new speakers' fronts are slightly in front of the cabinet, and at the outer edge of the wall. They are 10.5" off the back wall, KEF says something like 9" minimum, and recommended I stuff the port with their provided paper muffle (which I did). The new sub is about the same width as the old so should fit i the same spot, but unlike the old which is downfacing will face outward, so won't be in a cave of sorts from the furniture.

The center is right at the front edge of the glass top.

I may try putting the sub outside the towers, which would look better, but the seating in the area is at or somewhat outside where they towers are now, so that would make the sound at the outside seats worse, I think, if they are put in closer. As it is, they are a bit of a road hazard of someone going around those corners.

In this shot the console is probably 4" further forward than I hope to get it, I've got some balled up sub cable (it's like 30' and really heavy) that I need to fix by buying a new coax cable, which this is a good reminder of, thanks.

Advice welcomed.

View attachment 76742

I think you need to ditch the remote sub idea with the all in one unit and when the new sub arrives and after best placement is determined get a separate RF unit if necessary. Low frequencies and rooms are the nightmare that ruins good sound and I wholeheartedly commend you for the effort you have made, not many would have dove head first into this hobby at the beginning of their journey.

 

[Linwood]

...not many would have dove head first into this hobby at the beginning of their journey.

Bad analogy, it's diving in credit card first.

 

[everettT]

Bad analogy, it's diving in credit card first.

When I get the itch for more speakers the wife pulls out shotgun, lol. I've dropped some serious coin over the years relative to what my budget should have been and have never had buyers remorse yet. I've held onto speakers that worked for my ears probably too long after purchasing new.

The one thing I have learned over the years is that there a lot of electronics out there that are overpriced and provide no audible benefit just because of their name. Enjoy your journey and hope you enjoy the new subwoofer!

 

[Linwood]

So for those waiting with bated breath, this is the SVS in the same spot, everything defaulted, pure direct , no attempt at tuning anything.

The very low was clearly inability of the old speaker (orange) to reach low. The dips beyond that would appear to be the room?

I'll spend some time working with it, but the similarity makes me think the old one was "not that bad" (other than below 30hz), and should I actually just keep it and use both? (The 3800 can drive four independently with separate eq for each, as I understand it).

 

[lovinthehd]

So for those waiting with bated breath, this is the SVS in the same spot, everything defaulted, pure direct , no attempt at tuning anything.

The very low was clearly inability of the old speaker (orange) to reach low. The dips beyond that would appear to be the room?

I'll spend some time working with it, but the similarity makes me think the old one was "not that bad" (other than below 30hz), and should I actually just keep it and use both? (The 3800 can drive four independently with separate eq for each, as I understand it).

View attachment 76749

Pure direct with 2ch generally doesn't use the sub, can you elaborate on the setup?

Your avr can set level/delay for up to four subs, but they are eq'd simultaneously if using Audyssey.

Generally I'd at least want the subs to be fairly similar in performance, but prefer identical.

 

[Linwood]

Pure direct with 2ch generally doesn't use the sub, can you elaborate on the setup?

Your avr can set level/delay for up to four subs, but they are eq'd simultaneously if using Audyssey.

Generally I'd at least want the subs to be fairly similar in performance, but prefer identical.

The graph was from REW, which can send directly to the sub.

Audyssey may set them together but there's a manual EQ to balance them, as well as separate distances. (Now that it has that does not mean I know what to do with it).

I wasn't planning to buy two new subs. But the question I guess is whether I should discard the old Klipsch or keep it.

It does make the room look more symmetric; or maybe emphasizes their difference (but the baby has a blue light to make up, right?)

Honestly I have no idea what to do with the one sub to fine tune it, so I may just be silly thinking of having two. but I HAVE two, so will play around a bit.

I'm still lost in watching some of the tuning videos, to measure with REW to fine tune crossover (that makes sense) and distance (they seem to change that, which I assume changes delay, to fill gaps which is confusing).

 

[lovinthehd]

Thanks for the clarification; I take it you didn't run Audyssey? Or used it just to set levels/delays?

If you use the Denon's manual graphic eq, you lose the Audyssey eq; they don''t work simultaneously. Distance is the delay adjustment. The benefits of dual subs could well be better even with somewhat different subs. Experiment.

ps generally graphic eq is the least desirable way to do eq. PEQ would be better (but doesn't come with the Denon), and for now I'd let Audyssey do its thing and use it's setup, maybe even think about using Dirac. Limitation in positioning will be a factor, too.

 

[Linwood]

Thanks for the clarification. If you use the Denon's manual graphic eq, you lose the Audyssey; they don''t work simultaneously.

But there's a manual speaker level adjustment that I thought was on top of Audyssey. This one. You can't do an frequency specific change, but I could balance the relative power of the two subs, and this doesn't turn off Audyssey's curves, right? Below I've balanced them to the ear with whatever noise it plays (i.e. not sure at what frequency that concentrates).

Thanks for the clarification; I take it you didn't run Audyssey? Or used it just to set levels/delays?

If you use the Denon's manual graphic eq, you lose the Audyssey eq; they don''t work simultaneously. Distance is the delay adjustment. The benefits of dual subs could well be better even with somewhat different subs. Experiment.

I did run Audyssey but with the old sub. I will run it again when I finish experimenting.

I also ran A1 EVO Accoustica and loaded that into the other speaker preset. It did not sound better, it may have been worse. I put in the Harmon house curve with it, but I think it needs a bit more on the medium-high frequencies for my ear.

I'm watching the sales, thinking of either Dirac Live or Multeq-x, not because I know what to do with either, but I like toys with lots of knobs to screw up adjust with care. There doesn't seem to be much consensus which is a better choice.

Delays... I was watching a youtube last night about tuning subs (or more specifically one sub) and the guy was taking curves, seeing those big dips, then changing crossover and distance to smooth out the dips. I didn't get why delay would change it -- but I think in retrospect he must have also been sending the same signal to the mains, otherwise the crossover and distance would not seem to have an effect on the curve shape. But the delay would cause or prevent resonance and interference I guess.

Lots to learn.

 

[lovinthehd]

That's just a level adjustment, and you can alter both level and delay (distance) on top of Audyssey. Using an Audyssey setup with different speakers/subs/room/placement are going to require you to re-run it. I'd simply start with Audyssey, and recommend the $20 MultEQ Editor App for a bit more control/flexibility of eq you don't get in the avr alone before spending bigger bucks on MultEQ-X or Dirac.

 

[dolynick]

With both subs showing the same dips 50 & 70 Hz regions I'd say that confirms what several suspected earlier - that it is the room and/or placement within in.

In your case, with the older sub not really useful below 30Hz and the SVS doing strong output below 30 Hz (way more than I would have expected really), I would probably look into trying to solve the 50 & 70 Hz issues with the old sub. The only real option for dealing with that behavior is moving it elsewhere in the room. So take the old sub and start putting it in different places around the room and re-measuring it (you can probably unhook the SVS while you do this). Once you find a spot where the behavior in those two regions is more smooth and even, leave it there. Then reconnect your SVS and run the sweep with both again. You may fine that they start cancelling each other out at certain frequencies now, so this where you start to use the phase adjustment on one (probably the old one if the SVS with the mains is likely to be closer in phase with them already). What you're looking for is a phase setting where the two subs behave more additively rather than cancelling (so output goes up at the various frequencies, not down).

Don't get too worried about excessive output at certain frequencies. You can deal with those fairly effectively with room EQ. You're trying to eliminate the drastic dips below the reference/average level of the rest of the sweep. Room EQ can help with dips, but only a little bit. It is much more effective at removing excessive peaks. So you can use that to play to the strength of the tool(s).

Essentially what you're going to do is use the old sub to fill in that 50 & 70 Hz range the SVS is having trouble with where it is. And then let the SVS handle the deep bass as it seems to be doing very well with. Once you run Dirac or Audessey, they should hopefully blend well enough.

Alternatively, you could just ditch the old sub and do the placement crawl with the SVS by itself. You can probably do better in those regions but you'll likely find that it gets worse at others. This is why multiple subs are often recommended as it makes it easier to get even coverage across the whole spectrum.

 

[Kingnoob]

But there's a manual speaker level adjustment that I thought was on top of Audyssey. This one. You can't do an frequency specific change, but I could balance the relative power of the two subs, and this doesn't turn off Audyssey's curves, right? Below I've balanced them to the ear with whatever noise it plays (i.e. not sure at what frequency that concentrates).



I did run Audyssey but with the old sub. I will run it again when I finish experimenting.

I also ran A1 EVO Accoustica and loaded that into the other speaker preset. It did not sound better, it may have been worse. I put in the Harmon house curve with it, but I think it needs a bit more on the medium-high frequencies for my ear.

I'm watching the sales, thinking of either Dirac Live or Multeq-x, not because I know what to do with either, but I like toys with lots of knobs to screw up adjust with care. There doesn't seem to be much consensus which is a better choice.

Delays... I was watching a youtube last night about tuning subs (or more specifically one sub) and the guy was taking curves, seeing those big dips, then changing crossover and distance to smooth out the dips. I didn't get why delay would change it -- but I think in retrospect he must have also been sending the same signal to the mains, otherwise the crossover and distance would not seem to have an effect on the curve shape. But the delay would cause or prevent resonance and interference I guess.

Lots to learn.

View attachment 76751

Back when I got my onkyo avr I accidentally got the one model down from multi sub eq. Maybe you can get it to work a 8” and a 12”, my best sub isn’t even in usage. Wish I had gotten a hsu or svs not diy years ago.

 

[Linwood]

I've been experimenting a bit with the alignment tool, and the combined output seems much better (except at 128hz maybe) if I invert the smaller sub. The red is both set to normal/positive/zero, the blue is the same settings but the small flipped to 180 (I'm assuming 180 and inverted polarity are the same thing, there's only one switch).

Checking mains and new sub they work best with it normal. And according to the alignment tool this actually gets better with a slight delay change but I can't do that in pure direct and don't want to mix whatever audyssey has stored up with this.

I'm assuming with this the crossover needs to be 100-110hz .

Moving the subs elsewhere in the room involves getting new transceivers for remote. Delaying that until I need to.

I could swap the towers and the subs. For the small sub that probably makes a big difference as it's down-facing. For the new sub not so much as it's forward facing. I am not sure how much impact that has toward narrowing the effective sound stage of the towers, which is not a good thing. Though I guess I could swap then toe them out just a bit and break mostly even?

Anyway, lots of experimentation to do.

Oh.. the SVS has parametric EQ so if I can figure out what a "Q" is, without my mind drifting off into Star Trek, that may help.