Sub frowned upon for music set up?

[suri]

Hi Captain,

Been looking up in the net and this is the best description I found so far in Wiki:

"In particular, "transmission line" is the name of a specific audio speaker enclosure topology, in which sound from the back of the bass speaker chassis passes along a long (generally convoluted) path within speaker enclosure. The energy is absorbed on this path, or emerges from the open end in phase with the sound radiated from the front of the driver, enhancing the output level at low frequencies.
A typical transmission line speaker layout.

This type of loudspeaker enclosure was proposed in October 1965 by Dr A.R. Bailey and A.H. Radford in Wireless World (p483-486) magazine. The article postulated that energy from the rear of a driver unit could be essentially absorbed, without damping the cone's motion or superimposing internal reflections and resonance, so Bailey and Radford reasoned that the rear wave could be channelled down a long pipe. If the acoustic energy was absorbed, it would not be available to excite resonances. A pipe of sufficient length could be tapered, and stuffed so that the enegy loss was almost complete, minimizing output from the open end. No broad consensus on the ideal taper (expanding, uniform cross-section, or contacting) has been established."​

Given my very limited knowledge in hi-fi, I can only postulate that compared to sealed or ported subs, TL subs in theory should have no direct and/or residual resonance due to those culprits being absorbed by the transmission line. In the context of this thread, a sub that would be used for music should be crisp & clear, i.e., absolutely no resonance and any "after effects". And since the sub should be able to keep pace with the pace of the music, TL subs would fit perfectly given their ability to eliminate residual energy.

Now this is only my hypothesis. suri, venkatcr and other senior members can validate or invalidate this.

I would also be interested to hear from venkatcr about the comparison he is about to do with his Hsu sub! Can this be an item of interest for the next Chennai HFV meet?

hi thekinge -

the only type of subwoofer that really integrates with a high-end two-channel stereo system, IMO, a transmission-line -

By witchesofsound at 2009-07-24

the boy standing next to the transmission line sub-woofer is my 10 year old nephew (about five feet tall).

such subwoofers cost the earth to build - and i do not think they are available commercially - nobody would want such a massive monolith in the house - the subwoofer in the picture weighs in excess of 300 kilos (managed to weigh it recently in response to a query on another forum).

sealed subwoofers are too "tight" and sometimes "honky" (perhaps because the side-panels {6 of them} vibrate and produce undesirable harmonics) - and ported sub-woofers tend to be "single-note"

 

[thekinge]

...
the boy standing next to the transmission line sub-woofer is my 10 year old nephew (about five feet tall).

such subwoofers cost the earth to build - and i do not think they are available commercially - nobody would want such a massive monolith in the house - the subwoofer in the picture weighs in excess of 300 kilos (managed to weigh it recently in response to a query on another forum).

sealed subwoofers are too "tight" and sometimes "honky" (perhaps because the side-panels {6 of them} vibrate and produce undesirable harmonics) - and ported sub-woofers tend to be "single-note"

Thanks Suri,

I suppose I will be able to see "eye to eye" with the subwoofer because I am about 6 feet tall

6 feet tall, weighs 300 kilos and you built it yourself?! Hats off to you sir! I hope to listen to your WOE & TL sub one day If I may ask, how much did the sub cost you including materials, parts & labor?

If I can't audition / buy one that is readily available and one that weighs less, I can think getting TL sub built only after I permanently move back to India. Till then, I have to make do with a better quality sealed or port I suppose

On a side note, your nephew is only 10 years old and is already 5 feet tall?! They do grow fast these days

 

[arj]

I remember reading in an article by the head of PMC about how Transmission Line is perhaps the best way of getting a full range speaker But the complexities in designing and implementing the same is what scares many manufacturers away from doing it.

PMC specialises in TLs... not aware on any existing manufacturers who follow the same philosophy across their range.

Suri.. u truly are the Cool Dude Mahapurush in this Hobby

 

[suri]

Thanks Suri,

I suppose I will be able to see "eye to eye" with the subwoofer because I am about 6 feet tall

6 feet tall, weighs 300 kilos and you built it yourself?! Hats off to you sir! I hope to listen to your WOE & TL sub one day If I may ask, how much did the sub cost you including materials, parts & labor?

If I can't audition / buy one that is readily available and one that weighs less, I can think getting TL sub built only after I permanently move back to India. Till then, I have to make do with a better quality sealed or port I suppose

On a side note, your nephew is only 10 years old and is already 5 feet tall?! They do grow fast these days

hehehe thekinge -

when you get back to India - perhaps i will have the opportunity to build you something like this - even it is the last thing i do before i die!!

about what it cost me? - i will need some time to calculate! - will post here soon - i do remember calling myself insane! - and my carpenter said the same thing! -

regds
suri

 

[thekinge]

perhaps i will have the opportunity to build you something like this - even it is the last thing i do before i die!!

Hi Suri,

I am not sure if you're serious or joking, but I'm going to hold you on to this deal! But I pray that you live long enough to build the sub and see me using it for many years

 

[iaudio]

hehehe thekinge -

when you get back to India - perhaps i will have the opportunity to build you something like this - even it is the last thing i do before i die!!

about what it cost me? - i will need some time to calculate! - will post here soon - i do remember calling myself insane! - and my carpenter said the same thing! -

regds
suri

And I will steal it in transit from Kannur to Chennai! Muhuahuahua!
(Dhoom/fast n furious music plays in the backround!)

 

[thekinge]

And I will steal it in transit from Kannur to Chennai! Muhuahuahua!
(Dhoom/fast n furious music plays in the backround!)

Really, you think you can get away lugging a 650 pound machine so easily?! Not so fast Titus, not so fast! I will come back and intercept you Kamal Hasan style in the movie Vikram

 

[nshankar]

5. Finally a sub is not about providing the Punch but able to Extend the frequency of the main speaker as seamlessly as possible..and articulate the information in the same way.

Team,
Just added a REL T1 sub to my setup. Fully appreciate what you have mentioned. The REL T1 connects direct to the main speakers output ports to achieve this.

4. Integeration of a sub (ideally a pair) is not easy amd can take a long time..but if you do it right it is very well worth it.

ideally its delicate balance such that a sub should not be heard when on.. but really missed if it is off

Calibration of the sub is a challenge, but I am told that if done right, then it is the best. The delicate balance what you mentioned is something that I aim to achieve (hopefully!)

 

[randhir_s]

Music is felt and not heard. A proof of that is the experiment that Bose did on plants. There is a lot of information that we might not be able to hear but still do feel and therefore it is best to have a setup which has the widest possible frequency range