Kef TDM45B - Awful Sounds

[lovinthehd]

I'm located in Edmonton, AB, Canada.

For example, this Klipsch Black Label 10" subwoofer has a lower limit of 32 Hz.
Obviously, this is middle-of-the-line subwoofer but its not that cheap (especially considering it's used).

Then there's this SVS SB-2000 Subwoofer, which has a lower limit of 19 Hz.
As expected, it's quite a bit more expensive. I think if I was willing to drop that kind of money I'd be buying new though.

I don't really have a budget at this point. I already spent $300 repairing the plate amp so I'm a bit hesitant to spend more money at this point (hence why I'm trying to find a workaround). When I do decide to buy another subwoofer, I guess I'll make my budget what it needs to be to avoid having this problem again (within reason).

Not sure what the SB-2000 goes for new there, but that's a sealed box and you might be better served by a ported version (PB series from SVS). What does a new one cost (SVS is available in Canada)? I wouldn't bother with that Klipsch. How big a space is your room (in terms of room volume)?

 

[Pogre]

I do! I was wondering what this thing was.
Fortunately, the previous owner was very diligent in leaving me everything, down to the carboard boxes the speakers came in.

That is good news! Follow the instructions and mic pattern for measurements closely and make sure your mic is at ear height. You may even hear an improvement overall with a fresh calibration.

 

[soundB]

I ran Audyssey and one of the first things it had me do was adjust my subwoofer to 75 dB.
As I tried to accomplish this, I realized that volume knob on the subwoofer was not doing anything.
It wasn't until I toggled the THX button (it was originally pressed in) that the volume knob started to respond. It was also immediately much quieter, which leads me to believe that it was at full volume before! The Kef manual only states that the crossover frequency control would be inoperative when THX was enabled, but I guess that applies to the volume control as well.

After completing calibration, I watched the video that I generated those samples from. Those trouble spots no longer caused distortion but I also noticed the subwoofer was much quieter than before. I did a quick Google to get some context and came across an avforums thread where someone was complaining their subwoofer was too quiet after the running Audyssey. There were a couple of quotes that made me realize my subwoofer had been running way too loud previously (no wonder there was distortion):

When a subwoofer level is set correctly for music you shouldnt be able to "hear" it until you switch it off!
I know that sounds bonkers but what I mean is if you can notice something missing when its powered off but dont notice it when its on then the level/integration is near correct.
A lot of people have sub level set too high because they want to hear it.....

If you want hearing damage, exaggerated sofa shaking bass and highly annoyed neighbours, then override the Audyssey settings to achieve whatever it is you want.

Someone actually hinted at this earlier but it totally went over my head:

Part of the issue is it might be running way too hot. That could be due to taste, or getting used to it over time, or even trying to just get more deep bass.

I guess I was expecting the bass to boom all the time but I don't have a subwoofer that's capable of that, plus that's probably not conducive to a proper movie watching experience. In my defense, I don't have much experience with home subwoofers, my only point of reference is back in high school when the point of subwoofers in my trunk was to be as loud as possible .

TL;DR: Ran Audyssey, discovered that subwoofer was at full volume due to THX button, adjusted to a more balanced listening experience, distortion gone. Feel like an idiot but learned a lot and am happy. Thank you all so much!

 

[soundB]

Not sure what the SB-2000 goes for new there, but that's a sealed box and you might be better served by a ported version (PB series from SVS). What does a new one cost (SVS is available in Canada)? I wouldn't bother with that Klipsch. How big a space is your room (in terms of room volume)?

The reason I was thinking a sealed box would be better is because my subwoofer tucks into a nook under my projector screen. I figured a ported box would cause all kinds of rumbling in a closed space like that.

Looks like a new SVS SB-2000 goes for $1,200 CAD (on Amazon Canada).

My room is around 15' x 14'.

 

[Pogre]

I ran Audyssey and one of the first things it had me do was adjust my subwoofer to 75 dB.
As I tried to accomplish this, I realized that volume knob on the subwoofer was not doing anything.
It wasn't until I toggled the THX button (it was originally pressed in) that the volume knob started to respond. It was also immediately much quieter, which leads me to believe that it was at full volume before! The Kef manual only states that the crossover frequency control would be inoperative when THX was enabled, but I guess that applies to the volume control as well.

After completing calibration, I watched the video that I generated those samples from. Those trouble spots no longer caused distortion but I also noticed the subwoofer was much quieter than before. I did a quick Google to get some context and came across an avforums thread where someone was complaining their subwoofer was too quiet after the running Audyssey. There were a couple of quotes that made me realize my subwoofer had been running way too loud previously (no wonder there was distortion):



Someone actually hinted at this earlier but it totally went over my head:


I guess I was expecting the bass to boom all the time but I don't have a subwoofer that's capable of that, plus that's probably not conducive to a proper movie watching experience. In my defense, I don't have much experience with home subwoofers, my only point of reference is back in high school when the point of subwoofers in my trunk was to be as loud as possible .

TL;DR: Ran Audyssey, discovered that subwoofer was at full volume due to THX button, adjusted to a more balanced listening experience, distortion gone. Feel like an idiot but learned a lot and am happy. Thank you all so much!

Success! Glad you got that worked out. I had a feeling Audyssey might be able to help you detect the issue. A lot of folks do run their subs hot. You get used to it after a while and exaggerated bass sounds normal to you. The quote you shared about not being able to "hear" it until turned off is pretty spot on and what I shoot for too. Well, a lot of us will go in after calibration and bump the sub trim levels a couple of dB.

I'm also a fan of Dynamic EQ for my bass. It adds a little bit more oomph too. I don't know what level of Audyssey you have, but if there's a DEQ setting turn it on and see how you like it. If there's a "Dynamic Volume" setting or "Audyssey LFC" make sure those are turned OFF. Those will both nerf your bass if they're on.

 

[lovinthehd]

The reason I was thinking a sealed box would be better is because my subwoofer tucks into a nook under my projector screen. I figured a ported box would cause all kinds of rumbling in a closed space like that.

Looks like a new SVS SB-2000 goes for $1,200 CAD (on Amazon Canada).

My room is around 15' x 14'.

Sealed subs are just less efficient down low....a good sub of either design shouldn't "boom" though.

Glad you figured it out. You did no particular setup of levels/delays before I take it?

 

[soundB]

Success! Glad you got that worked out. I had a feeling Audyssey might be able to help you detect the issue. A lot of folks do run their subs hot. You get used to it after a while and exaggerated bass sounds normal to you. The quote you shared about not being able to "hear" it until turned off is pretty spot on and what I shoot for too. Well, a lot of us will go in after calibration and bump the sub trim levels a couple of dB.

I'm also a fan of Dynamic EQ for my bass. It adds a little bit more oomph too. I don't know what level of Audyssey you have, but if there's a DEQ setting turn it on and see how you like it. If there's a "Dynamic Volume" setting or "Audyssey LFC" make sure those are turned OFF. Those will both nerf your bass if they're on.

Thanks for that, I enabled both dynamic EQ and dynamic volume. I'll be sure to disable dynamic volume!

By the way, I think Audioholics is the best forum on the internet.
I've never had so many folks eager to help me and excuse my total lack of knowledge.
You guys all ROCK!

 

[soundB]

Sealed subs are just less efficient down low....a good sub of either design shouldn't "boom" though.

Glad you figured it out. You did no particular setup of levels/delays before I take it?

Good to know, I guess my discrimination against ported boxes was unfounded.

Correct, I'd never done any setup before.
As I mentioned prior, I inherited all of this equipment from the previous owner of my house and, having no experience with this sort of stuff, I basically left it as-is (if it ain't broke, don't fix it).
However, having to get the subwoofer repaired kind of shook things up. Honestly, I probably pressed the THX button when I was putting it back thinking "THX good, right?" and this entire situation was caused as a result.
If it wouldn't have done that, I probably would've just put it back in and gone on along my merry way in the bliss of ignorance. But hey, I got to learn a whole bunch about my setup as a result, so not the worst thing that could've happened.

 

[Pogre]

Thanks for that, I enabled both dynamic EQ and dynamic volume. I'll be sure to disable dynamic volume!

By the way, I think Audioholics is the best forum on the internet.
I've never had so many folks eager to help me and excuse my total lack of knowledge.
You guys all ROCK!

Aw, shucks. Much obliged!

I might be a little bit off here, but to my understanding Dynamic Volume lowers dynamics across the board for stuff like late night watching. You can turn it up loud enough to hear dialogue and sudden explosions or spikes in volume won't wake folks up in the next room. Audyssey LFC (Low Frequency Containment) does a number on your bass. Also in the vein of not disturbing those close by.

If your DEQ has Reference Level Offset, that affects how much DEQ (let's just say "bass boost") is applied. 0 being the most and 15 the lightest.

 

[soundB]

Just wanted to give a final report for the sake of closure (and for anyone reading this in the future).

I watched a movie last night to give the subwoofer a real test. Unfortunately, I was still able to detect some distortion, though nowhere (and I mean nowhere) near what I was experiencing before. I likely wouldn't have noticed it prior to this whole experience but since I've become accustomed to listening for it, I heard it. Anyhow, I went to Onkyo's equalizer and dropped the 20Hz setting of the subwoofer section to -6 dB and didn't notice any distortion after that.

My system is now in a state that I can live with for the time being (I can now watch movies without wincing!) but I think I'd like to purchase a new subwoofer down the road. Looking forward to reenlisting all of your expertise when the time comes.

Thanks again!

 

[William Lemmerhirt]

Glad you found at least a workable solution. And don’t worry. Well be happy to spend your money when the time comes! Lol

 

[Zteinorw]

I had a problem when it was New. A wall inside was vibrating on low frequency, looked like it was not glued(bad production?) . After agreement with the dealer, i used epoxy. Fixed the problem. Now I got New issue.. The thx on off switch is bad. Its a blue 12 pin switch. Where can I find a New?