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Old 24th August 2006, 17:20   #46
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Originally Posted by blueraven316
Soomoku doing R&D for audiobahn......................................... ...............I may have darshan of the root of such controversy, till then ...............
Ok i found out more about SOOMOKU. This is the best i can do:

1. Their active 10" tube is sold by Audiobahn at ATB10AT. It has a
class AB Mono amplifier.

2. The 12" sub ( the one that i have in my car) has been jointly developed with Velodyne (American firm that specializes in home and professional subs)

3. The sub i have in my car is a 12 inch, vented box active subwoofer. It is powered by a 225 watt rms continuous class D amp (they call it Class-X for some reason)

4. I like the sub for 3 main reasons. A) Accuracy of the bass b) Quick cone reaction. This is very discernable, especially if you listen to rock(drums) or Jazz(Double Bass) where notes are played in quich succession.

5. The 12" class-D sub has a 0 - 180 degree continuously variable phase control. This can be really useful while fine tuning the performance.

6. SAM maybe i should take your advise and start promoting SOOMOKU. should have a talk with Palesha. I think it can do wonders with some marketing. I am not being sarcastic here. And besides, im really getting bored making software for the last 5 yrs

As for their affiliation with AudioBahn, i made some concrete enquiries and found it to be true. A lot of this work is done in AudioBahn's facility in china (i think in Shenzen). Soomoku's contibution is specially in the areas of enclosure design and managing air pressure levels inside the enclosure . One of their recent developments is a special chemical process to treat the MDF used. This process supposedly reduces the porosity of MDF used in the enclosures and thus greatly enhancin their acoustic properties.
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Old 24th August 2006, 17:37   #47
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Originally Posted by vikramshetty101
One of their recent developments is a special chemical process to treat the MDF used. This process supposedly reduces the porosity of MDF used in the enclosures and thus greatly enhancin their acoustic properties.
the mdf normally made up is normally of wood dust and resin. they are kept under pressure and heat so that they are bonded together....there are many type of mdf avalable in the market which have good outer layer but bad inner layer. and all of them are I think are very much non-poros due to the process from which it is made.....

in ur profile u live in delhi u can join in the meat this sunday and we can discuss and audit ur sub also........

http://www.team-bhp.com/forum/team-b...08-2006-a.html

Last edited by low_bass_makker : 24th August 2006 at 17:39.
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Old 24th August 2006, 17:43   #48
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thanks vikram!

I talked to a friend who was involved in designing a classD amplifier (in a commercial chip, not DIY) and asked him to give me an overview of its operation. Here is what I got- it converts PCM (raw digital samples, which are generally 16 or 24 bit) into another digital kind of signal (single bit) which is coded either as pulse width modulation or pulse amplitude modulation, instead of conventional analog signal created by DACs. This signal is amplified directly, usually using MOSFETs. It contains original signal plus other higher harmonic components which need to be filtered out. These generally result in relatively high THD, and is not used in high end applications. However, there are high end versions of classD as well where closed loop systems are used for accurately removing harmonic distortion to make THD acceptable. That puts a question mark as to which type of classD it is, ordinary or high-end! It is not a good idea to generalize all classD as low-end products. Instead we should make sure that THD figure is good...and that the same should reflect in its performance!

KB you are right, classD is efficient... thats the main advantage (nice for battery).
I think since most of the power is required for subwoofers, that makes it suitable for them, especially in cars.
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Old 24th August 2006, 18:12   #49
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Originally Posted by santosh.s
KB you are right, classD is efficient... thats the main advantage (nice for battery).
I think since most of the power is required for subwoofers, that makes it suitable for them, especially in cars.
class D amps are not digital amps they just named as d class to differciate from the other classes

the D class are very efficent amp nealry 80% some times and only 20% is lost in heat thats why they are used in car audio as the power has to be full utilise.....

also some new breed of d class are full range amp with better spec than our ab class....

http://en.wikipedia.org/wiki/PWM_amplifier

http://www.6moons.com/showcase/nuforce/nuforce.html
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Old 24th August 2006, 20:04   #50
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Hmm, Vikram, No Offence ! but, the way you are putting in bulletpoints for SoomoKoo , it is obvious that people will think you are marketting for them,
Anyways, Blueraven and myself are in the Audio Industry , he handles the bangalore branch of our business, and trust me, in india The Audio business is a lot lot more than putting in points, and proving how good a product is, there are a lot of products that are good but lack branding so are not what you can call today is " JBL " in India.
Dig into the business , you will know. Analysing on facts is easy, working on Practicality is an entirely different ball game, We will surely look at SoomoKoo when we get a chance.
Cheers !
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Old 25th August 2006, 01:43   #51
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Quote:
Originally Posted by vikramshetty101
3. The sub i have in my car is a 12 inch, vented box active subwoofer. It is powered by a 225 watt rms continuous class D amp (they call it Class-X for some reason)
In China, for some reason, they call hoes "chicken", and gigolos "ducks". I think it comes naturally to them. As long as they make the speakers right, we shouldn't bother.

Quote:
Originally Posted by vikramshetty101
4. I like the sub for 3 main reasons. A) Accuracy of the bass b) Quick cone reaction. This is very discernable, especially if you listen to rock(drums) or Jazz(Double Bass) where notes are played in quich succession.
You said you were a musician, didn't you?. Anyway, I was too, until they started paying me to STOP playing. It was rather lucrative, so I did.

Anyway, a rock drumkit and the double-bass play different frequency bands, in that the drumset only partly overlaps the region that is reproduced by a car subwoofer. And that is the bass drum or kick drum. And if you're talking about the double-bass that is a 2-pedal modification of the regular kick-bass pedal, that isn't much of an exception. The Toms (& Jerrys) and the Snares are much higher, and they should be cos they ought to be directional. Usually drum-rolls (for more on drum-rolls contact Gunbir, for more on Chicken rolls contact LBM, For more on dating...you're in the wrong forum), are accomplished without using the kick pedals. And since these are directional, and I dont want a Koomolu playing that in my trunk! I'll have my front speakers play it. I want the stereo feel and the intended & oh-so-natural pan! So how is the sub so responsive? You have subs in the doors? Unless you got a lot of music with kick drum rolls..and that sounds eerie and boring except "Metallica - The One"! No?

Quote:
Originally Posted by vikramshetty101
5. The 12" class-D sub has a 0 - 180 degree continuously variable phase control. This can be really useful while fine tuning the performance.
But it takes a lot of time, like you said. So I'll still go with the one that's ok without continuous phase alignment.

Quote:
Originally Posted by vikramshetty101
6. SAM maybe i should take your advise and start promoting SOOMOKU. should have a talk with Palesha. I think it can do wonders with some marketing. I am not being sarcastic here. And besides, im really getting bored making software for the last 5 yrs
You should. Soft-ware isn't any good like you just said, that's why they invented Viagra.

Quote:
Originally Posted by vikramshetty101
As for their affiliation with AudioBahn, i made some concrete enquiries and found it to be true. A lot of this work is done in AudioBahn's facility in china (i think in Shenzen). Soomoku's contibution is specially in the areas of enclosure design and managing air pressure levels inside the enclosure . One of their recent developments is a special chemical process to treat the MDF used. This process supposedly reduces the porosity of MDF used in the enclosures and thus greatly enhancin their acoustic properties.
There's a difference between "I think" and "I know". And it can't be concrete when you still say that "I think"??? Do you want to think again, or do you know? In case you don't really know and you just think, don't you think that's a rather irresponsible statement at the expense of some multi-billion dollar company? In that case, don't you think you have somehow been rightly reprimanded in the past?

Do you think or do you know that MDF is porous?

Could you please let me know what this air-pressure level management is? How it works, I'd be glad to know. In addition to metallurgy, I studied some aerodynamics too. Call it Fluid Mechanics if it suits you.
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Old 25th August 2006, 09:20   #52
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Originally Posted by low_bass_makker
class D amps are not digital amps they just named as d class to differciate from the other classes
what differentiate conventional amplifiers and classD is the signal for which power amplification is done. In conventional class A, B or AB it is alwas analog signal which represents original audio information. Whereas in classD its PWM representation, which has more of digital form (on/off), definitely not analog. Apart from PWM there are better coding techniqes also like sigma-delta or SPDIF (don't ask me about details, though!) which again fall in digital category. Whats in the name anyway, only the technology and its end results matter!

What I had explained was a classD system where a DSP processor is used to accurately generate PWM directly from samples. But I can't expect the sub under consideration to read samples directly. It must be taking analog signal itself (preamp output from head units) and converting it into PWM internally using some other (easier and cheaper!) technique. Something like the example given in your wiki link.

These are excellent readings, very informative. I was impressed by nuforce claims, especially regarding bandwidth, damping factor, phase accuracy and distortion/noise. However, I don't think these would be really affordable to many. Couldn't find any price information even on their own home-page (nuforce.com).
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Old 25th August 2006, 10:45   #53
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Quote:
Originally Posted by vikramshetty101
2. The 12" sub ( the one that i have in my car) has been jointly developed with Velodyne (American firm that specializes in home and professional subs)

As for their affiliation with AudioBahn, i made some concrete enquiries and found it to be true. A lot of this work is done in AudioBahn's facility in china (i think in Shenzen).
VIckram,

I dont doubt your claims but are you are liberty to tell us who told you all this.

Companies like REL and Velodyne are some of the better commercial subwoofer manufacturers. There are many others but a lot of these are the Pros (read as PA and SR). I find it hard to believe that the products I heard had any inputs from Velodyne.

I know less about Audiobahn than Velodyne and would be very pleased (thrilled if must ask) if anyof Palesha's collaborations were true. To me it would mean that we in India can atlast get products of world class quality at prices that are commensurate with our earning ability.
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Old 25th August 2006, 11:00   #54
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Originally Posted by navin
Companies like REL and Velodyne are some of the better commercial subwoofer manufacturers...I find it hard to believe that the products I heard had any inputs from Velodyne.
Yup. Having used a lot of Velodyne, that doesnt sound right to me. They do have asian manufactured products in the entry level segment. And they could be sharing some common parts sources, like for cabinets, or spikes, or whatever. But based on the sound I heard from Soomoku stuff, I can be sure there is no truth to this "co-designed by Velodyne" claim...
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Old 25th August 2006, 12:22   #55
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Originally Posted by Bass&Trouble
For more on dating...you're in the wrong forum
Ahem. B&T apparently the grey coloured goose has made you forget me.

So I'm a musician and here's my song:

Some people are diplomatic and wise, they are called navin
Some people are knowledgeable and wise, they are called gunbir
some people are a little high, knowledgeable and very smart mouthed & they are called B&T
I'm just a simple guy but i know the smell of horsedung when it hits me...

Chorus: When the horsedung hits me
ooohooo when it hits me


I know you don't know the tune, but it sorta sounds like a coldplay song. (Especially the "Hits me" bit)

Vikram i read your claims about Kokomo designing stuff for Audiobahn and Velodyne and I do not believe it. I think you are wrong and your source (since you say you found out) is feeding you ummm.... what's the word here?
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Old 25th August 2006, 12:28   #56
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Quote:
Originally Posted by Sam Kapasi
I think you are wrong and your source (since you say you found out) is feeding you ummm.... what's the word here?
The word eh??.....Horsedung....
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Old 25th August 2006, 12:47   #57
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Hmm after going through the various posts for the last couple of days i can see that..

1) Most of the audio gurus feel that the Soomoku subs are not value for money based on their listening experience.

2) There are few people who think otherwise about the quality of the subs. I get a feeling that people are desperate to prove a point here and maybe there are counter points to disprove the points aswell.

Something tells me that the name of the brand and its origin in a way might have had a bearing on the listener's perception of the speakers capability.

Maybe a blindfold test of few of the brands including the brand under question would settle things to an extent instead of digging into the history, affiliations, collaborations, expertise and all those jazz.

Last edited by muni : 25th August 2006 at 12:53.
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Old 25th August 2006, 13:06   #58
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Originally Posted by muni
Something tells me that the name of the brand and its origin in a way might have had a bearing on the listener's perception of the speakers capability.
Muni, I am an indian first and an audiophile second. I promise you that I would be happeist and most thirlled person on this forum if Palesha's sub was any good. Others here (Sam, B&T, Gunbir etc.) who know me would second this.

I have not heard the lastest incarnation so my opinions are based on older versions (and my earlier posts have been qualified as such).

There are a few Indian manufactuers (Cadence for example) that are doing a reasonable job given their infrastructure and finances and I applaud them. I sincerly hope that Palesha gets the same credit. But credit is earned.

as far as AVMax giving Palesha a Best Buy rating is concerned that is the opinion of the reviewer at the time. AV Max itself has come a long way since.

The Indian audio scene was very active in the 70s then video distracted us for about 30 years and the audio scene has only lately gotten active thanks to HT/AV. We still have a long way to go.

Last edited by navin : 25th August 2006 at 13:07.
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Old 25th August 2006, 13:54   #59
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Originally Posted by gunbir
And they could be sharing some common parts sources, like for cabinets, or spikes, or whatever. But based on the sound I heard from Soomoku stuff, I can be sure there is no truth to this "co-designed by Velodyne" claim...
That seems to be the reason for the misleading information. Rightly explained.

Velodyne and Audiobahn SURELY have better things to do. (Here I'm not saying "I think")

Just because you made a concoction from some commonly used parts, doesn't in any way translate into having 'assisted in R&D'.

When someone from Booboolu did probably assist, the 'super-slim coaxial high-end car speaker' turned out with an Fs of 180 Hz. The first part of the statement is an assumption. The second part is definitely true.
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Old 25th August 2006, 15:59   #60
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Originally Posted by Bass&Trouble

You should. Soft-ware isn't any good like you just said, that's why they invented Viagra.
HA HA !!!

Quote:
Originally Posted by Sam Kapasi

Vikram i read your claims about Kokomo designing stuff for Audiobahn ................

Chorus: When the horsedung hits me
ooohooo when it hits me
LOLOLOL !!!

Quote:
Originally Posted by Bass&Trouble

When someone from Booboolu did probably assist .........
I Just Fell off the Chair ............. MUUHAHAA

Last edited by 929RON : 25th August 2006 at 16:07.
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