Low bass in music - Sub or no Sub ?

[Thad E Ginathom]

OK... quite willing to eat my words if I got it all wrong. I'm a beginner at this stuff.

Have a morning function, so have to sleep tonight (rather than tomorrow morning, my usual hours) so will get back to this in a day or two...

I think we have HFVers who know the room treatment stuff too?

 

[captrajesh]

OK... quite willing to eat my words if I got it all wrong.

C'mon Thad, the intention of countering and even crossing swords on some occasions is not to put someone in a sticky corner; it is only to enrich the community with the right knowledge. I'm certain that you would empathise with me.

Have a morning function, so have to sleep tonight (rather than tomorrow morning, my usual hours) so will get back to this in a day or two.

HFV is not be all and end all. We have our private lives too. I do understand.

I think we have HFVers who know the room treatment stuff too?

Yes I hope knowledgeable FMs would chip in with their views. I'll be happy to be proven wrong too.

 

[Fantastic]

......Pardon my ignorance; Are you referring to ported design? IMHO, even TLs and folded horn designs could also be broadly classified as ducted speakers and hence confused.
If ported is what you've meant, as per my personal experience, sealing the port by stuffing a rolled on sock would significantly reduce the bass response. I'm not sure if by sealing the box and modifying the crossover would result in better bass response.......

It doesn't really matter what anyone would want to call it. Usually a ducted box was referred to a bass reflex cabinet. But we are interested in what it does when modified. A sock is actually not a good enough seal. You'd need to block it with something more 'solid' . To experiment you could use a bottle that just about fits the duct and build up the diameter with a few layers of cloth to give you a well sealed fit. It will give you less bass because the Fr goes up. With a reflex box with a 60Hz roll off , it went up to 90Hz when the duct was sealed. You will have to measure Q and the Fr of the system. With that you can make a LR crossover to match it to give an accurate overall acoustic 4th order LR rolloff.
Removing large excursion signals from the main speakers will audibly clean up the midrange. But of course as you have now reduced the LF you will need to add an appropriately crossed over sub. It isn't always easy to get a good match. Bass heavy male voice can supposedly go down to 65 to 80 Hz ! This means that even with a 60 Hz 4th order crossover on the sub you might still get 'some' voice through the sub while playing male vocals with bass heavy voices. But this probably will be quite rare I guess.

Isn't it fun ? SO MANY variable factors to deal with and no single best answer ! Keeps one completely occupied and the beer flowing endlessly !

Might add that the more you know,you find out that you actually know very little ! To sober us up we need more beer !

 

[captrajesh]

It doesn't really matter what anyone would want to call it. Usually a ducted box was referred to a bass reflex cabinet.

From what I've read up, (which is quite little; I admit) a bass reflex cabinet was commonly referred to as a ported cabinet and hence the confusion.

A sock is actually not a good enough seal. You'd need to block it with something more 'solid' .

Totally agree; I was just referring to my home experiments wherein I could control boominess of speakers using that technique.

To experiment you could use a bottle that just about fits the duct and build up the diameter with a few layers of cloth to give you a well sealed fit.

If a lossy sock could reduce the bass response, it is quite logical that proper sealing of the port would do it even better. No argument.

Removing large excursion signals from the main speakers will audibly clean up the midrange.

Can't agree more.

But of course as you have now reduced the LF you will need to add an appropriately crossed over sub.

Glad to know that we are on the same page. Now that it is clear that we need to add a sub for augmenting the bass, there is no scope of argument from now on.

Might add that the more you know,you find out that you actually know very little ! To sober us up we need more beer !

Again, can't agree more.

:cheers:

 

[manoj.p]

OK... quite willing to eat my words if I got it all wrong. I'm a beginner at this stuff.

Have a morning function, so have to sleep tonight (rather than tomorrow morning, my usual hours) so will get back to this in a day or two...

I think we have HFVers who know the room treatment stuff too?

Well, I am not an expert on room treatments, but my understanding is this.

The subwoofer range is prone to standing waves and room modes. These cancel the original sound wave coming from speakers causing nulls or reduction in db levels at certain locations. If the listener happens to be in those locations of subs, he will not hear sound at the full levels. If one puts bass traps, it absorbs the wave when it hits it, and there is no reflection wave and if that mode is gone, then there is nothing causing cancellation. This way, the listener will be able to hear the source sound.

However, there is a catch, to absorb the sound wave completely, one needs bass traps several feet deep. Lets say at 80 hz, the sound wave is 14 ft long. to absorb it completely, we would need a bass trap at 3.5 ft deep.

hope this helps.

 

[Thad E Ginathom]

C'mon Thad, the intention of countering and even crossing swords on some occasions is not to put someone in a sticky corner; it is only to enrich the community with the right knowledge. I'm certain that you would empathise with me.

Oh.... I didn't mean it in a negative way! Word eating is good where finding out I'm wrong about something means learning. No negative implications.

(There was a deeply nasty PM of my mother country who said something like, "I've often had to eat my words, and I find them a very good diet." He was a very unpleasant man, but clever at one liners. Oh, he had a certain knack at winning wars too :lol

HFV is not be all and end all. We have our private lives too. I do understand.

:lol: But hey, I do prefer my owl hours! Still it was a good function, including release of DVD on life and music of mridangam mega-maestro Palani Subramaniam Pillai

Yes I hope knowledgeable FMs would chip in with their views. I'll be happy to be proven wrong too.

Google here I come! I wish there was some system to bookmark links and automatically index them by why I thought they might come in useful

But...

Well, I am not an expert on room treatments, but my understanding is this.

The subwoofer range is prone to standing waves and room modes. These cancel the original sound wave coming from speakers causing nulls or reduction in db levels at certain locations. If the listener happens to be in those locations of subs, he will not hear sound at the full levels. If one puts bass traps, it absorbs the wave when it hits it, and there is no reflection wave and if that mode is gone, then there is nothing causing cancellation. This way, the listener will be able to hear the source sound.

However, there is a catch, to absorb the sound wave completely, one needs bass traps several feet deep. Lets say at 80 hz, the sound wave is 14 ft long. to absorb it completely, we would need a bass trap at 3.5 ft deep.

hope this helps.

Yes, it does help, but ...3.5ft deep? Does this mean that this is one of those things that works well in tough but is tough to achieve in practice?

 

[manoj.p]

Yes, it does help, but ...3.5ft deep? Does this mean that this is one of those things that works well in tough but is tough to achieve in practice?

Yes sir. That's why taming very low frequencies is very tough. There other traps like Deep bass trap (which uses a plywood membrane+airgap+thermal insulation) and Helmholtz resonator etc.

And then there is the most effective way of using multiple subwoofers spread appropriately in the room depending upon room modes.

 

[Thad E Ginathom]

Well, I just spent a short time with one or two of my old bookmarks and google. I came up with a couple of Audioholics links here and here ...and here.

Useful stuff can be done while still leaving some room to move around!

But doing it could cost as much as some of us spend on our hifis. Oh well...

But I would love to try doing something like this.

(which actually costs similar to buying a pair of flagship headphones. And if I had the room I wouldn't need the headphones. Can anyone see any reason why Mrs G shouldn't go along with that? )

 

[manoj.p]

Yes, it can be quite tricky, thats why multiple subwoofers help. They can go quite low and give you headroom + less distortion as we have to turn down the gain knob on those.

 

[gobble]

I use a rolled up thick woolen carpet 7ft long as a bass trap. It looks innocuous enough lying in the corner of the living room waiting to be unrolled.

G0bble

 

[jagdish_p]

I have finalized REL T7. I'll post a review once I get it.

Did you get the Sub? Waiting for your review

BTW how much does the T7 cost and from where?
Thanks

 

[Shivam]

Did you get the Sub? Waiting for your review

BTW how much does the T7 cost and from where?
Thanks

REL T7 has been quoted at INR 89,000 by Sound & Vision, Pune. Transporting is a problem from there and secondly the price is high for me. I am searching other sources for it now.

 

[manoj.p]

Wow, 89000 is approx $1500. That's a lot of money for a 10" sub-woofer with 200 watts amp. HiFi equipment is indeed very expensive in India.

On another note - If you are looking for the organ music play, then don't even look below 15" woofer. Even a single 15" driver won't be able to play it that well. Anything below and you will still be unsatisfied. I would definitely audition the sub if I have to pay that much money.

 

[mpw]

Wow, 89000 is approx $1500. That's a lot of money for a 10" sub-woofer with 200 watts amp. HiFi equipment is indeed very expensive in India.

On another note - If you are looking for the organ music play, then don't even look below 15" woofer. Even a single 15" driver won't be able to play it that well. Anything below and you will still be unsatisfied. I would definitely audition the sub if I have to pay that much money.

============================================

agree..

the key is the keep the volume level as low as you can and yet feel the bass.

mpw

 

[hydra]

As a separate option, do check with Kanwar also.

hifiashok uses a Avepa Sub with an active XO (both made by Kanwar). The sub is 21". (whoa!)

EDIT: http://www.hifivision.com/active-speakers/23553-avepa-zyphers-z-21-active-subwoofer.html

 

[Thad E Ginathom]

Wow, 89000 is approx $1500. That's a lot of money for a 10" sub-woofer with 200 watts amp. HiFi equipment is indeed very expensive in India.

On another note - If you are looking for the organ music play, then don't even look below 15" woofer. Even a single 15" driver won't be able to play it that well. Anything below and you will still be unsatisfied. I would definitely audition the sub if I have to pay that much money.

It's looking like a huge amount of money to spend to reproduce just one genre of music better --- but if that genre is important to Shivam, well, fair enough.

Also, people say that subwoofers add weight to frequencies a little further up the scale too, so it should give an improvement to more than just long, long organ pipes.

 

[manoj.p]

It's looking like a huge amount of money to spend to reproduce just one genre of music better --- but if that genre is important to Shivam, well, fair enough.

Also, people say that subwoofers add weight to frequencies a little further up the scale too, so it should give an improvement to more than just long, long organ pipes.

Yes, agree with the part of spending money on something that you want/like. But spending Rs 89000 on that 10" subwoofer will not get Shivam what he wants. That sub may reinforce some frequencies but is nowhere capable of producing the organ music that he craves. It can probably do above 30 Hz.

Its a lot of money for a sub that can't do the thing you wanted in the first place. If I were to spend that kind of money, I would not buy blind. I will audition the sub and if I can't - then I will check for measured output on internet sites like data-bass.com

By comparison - Data-Bass this sub is measured to give output till 12.5 Hz. Rhythmik also sells a cheaper and smaller DIY kit. That's what I would look in a sub. If he has to buy local, then contact Kanwar in Delhi and see what he can do.

 

[Shivam]

I got a chance to try a REL T7 sub before finalizing and it did bring out the organ music very nicely. One of the biggest advantage with REL is its ability to use the signal from speaker level connections (without adding or removing anything much) which makes it ideal for an active system like mine.

 

[manoj.p]

Okay, that's perfect and you have done all your homework. See if you can get it from nearby dealer.

 

[captrajesh]

Rhythmik also sells a cheaper and smaller DIY kit. That's what I would look in a sub.

Which one are you recommending? DS1200 CI - Direct Servo subwoofer or GR Custom Install?