t/s specs for indian drivers

[somakmaitra]

hi ,
does any body have the t/s spec of bolton or any other indian made woofers ?
the speaker shops in calcutta have never heard of the t/s parameters !!!

which is the best indian dome teeter ?
i am quite pleased with the philips dome but it cannot handle high output.
any suggestions will be welcome .

regards ,
somak

[sangram]

Well, well, well...

I remember someone saying around here that Bolton has some specs on their site. The best bet if you're depending on in and around these parts is the stuff from Peerless in Mumbai, but I have no clue about that stuff. I prefer buying prebuilt. Expensive but far superior to anything that you can make with stuff available in India.

Apart from that, most Indian drivers are dark, dirty and have no sense of traffic rules...

If you still insist on going DIY, I would stick with the Philips dome, or go for the Motorola Piezo horns. Stay away from those Bolton Dome tweeters. They fail with the 12 dB crossovers, only an active 24 dB/octave active system can keep them happy. Same story with the Philips silk dome. Since they are high sensitivity, they do not need much power if you cross them over intelligently. However all of these guys have problems with the commonly available passive XOs.

I have never got good results using the locally made drivers including Bolton. Not tried Peerless. Some guys sell an 'imported' 'Sony' 'Woofer' that is even worse, poor excuse for a speaker. A few have started manufacturing halfway decent speakers, which are cheap so it can't hurt to try.

Best would be if there was a way to actually measure the T/s yourself. Such methods exist, but I dunno what they are.

I have built quite a few pairs, the only ones I like are some 12" woofers that I have actually 'heard' at 16 Hz... But they're 12". Tough to implement...

[navin]

the best drivers that a DIY can lay his/her hands on yet made in india and sold in india albeit sprodically are ones made by peerless INDIA (PI)

that said there are other methods to get good drivers in India.

1. import them direct. today drivers are OGL (Open General Licence) and yo can import them from Madisound or whatever (there is one person who imported from singapore)

2. A few manufactuers are DIY friendly a dn will sell excess stock of decent imported drivers to DIYers. I hear Norge (Bombay) or Torvin (Madras) are 2 such manufactuerers.

3. Salvage them I have a friend who manged to salvage some nice 8" and 12" woofers from a Celestion system and added a PI 5" and 1" and made a 4 way.

The only time locally made good drivers were freely available in India was in the 70s and 80s (around 76-81). Philips India used to make a wide range including a nice 12" and 5" woofers, 5" cone and 2" dome mids and a 2" cone and a couple of 1" dome tweeters. They also made a 7" full range. The T/S specs were not bad. Manufactuers like Arphi, Sonodyne and Cosmic used the make their owhn drivers that could also be bought retail. Then Video killed Audio and that was the end of that.

Today Arphi makes ear plugs, Cosmic make motorcycle helmets, Sonodyne concentrates on exports.

[sangram]

If, however, you are intersted in Sonodyne stuff, I happen to know Anindya fairly well and can hook you up with him. He will drop a little price on some of his material if you buy direct, but I don't know about components and excess inventory, maybe you will have to ask him separately...

Edit: Navin: What duty is payable for drivers, if someone were to say, buy from PartsExpress? I may be able to buy some stuff...

[somakmaitra]

well thanks a lot to both of you ,

regarding the custom made drivers is it possible to make a drive by importing the basket , voice coil and surround and mating with a local cast frame and good quality magnet?

regarding the philips i am having the problem of blow tweeters .

for measuring the t/s parameters i sugest you go for speaker workshop software ,its a freeware , or you can download a signal generator software .and use a multimeter and resistor for measuring it . you can go to the ron elliot site sound.au.com

regarding imports i am quite afraid with the customs department .

regards
somak

[navin]

1. you can make a driver by importing parts in fact parts attract a lower duty rate. but i would not bother. you need precision machine to asseble the driver. even small manufactuers like palesha import their drivers (in this case a 12") from outside (usually China).

2. China made drivers are quite nice to look at. the T/S specs are all over the place but so are indian drivers. if you import 20 6" woofers you might 4 that match but 20 chinese 6" woofers are still less than 2 SS woofers. On the other hand 2 6" SS woofers might probably slip past customs without much of a bother. China made tweeters are also erratic the power handling is fine but they are very hard on the ear. There is one manufactuer that makes good stuff i forget the name. also vifa makes it's logic line in china if you can ask vifa thailand (it handles india) to ship you these I think you can get good cheap drivers with relaiable T/s specs.

3. Anindya is a nice guy. I have met him a few times when he comes to Bombay. I am trying to convince my art deco oriented father in law to put in a surround sound system based on 5 Genie 2s and a Palesha or Sonodyne sub.

4. the customs have improved of late. the duties i think are 50% duty, 28% CVD, 4% Octroi (bombay only). duty is on CIF value. CVD is on value incl. duty. octroi is on CIF+duty+CVD. enjoy. duty on parts is 30%. it pays to hire a GOOD, HONEST clearing agent.

[navin]

how many indians are there on this forum? anyone have a count? if you want email me direct.

[Cacophonix]

An indian newbie from texas here!

[sangram]

Me too...

Also the latest issue of AVMax has some joy in regard to specially this discussion.

There somebody called SanTen in Mumbai who is importing and seems one can talk to him. I will shoot off a mail to him tonight and will keep you guys posted. Maybe one can be lucky...

[somakmaitra]

well thank you very much to you both navin & sangram for ur valuable suggestion,
the sonodyne speakers are a real gem and they are probably the best designed bass reflex enclosures speakers in india . they have a very flat response and very sweet treble .
but people have developed wrong impression about sonodyne , half of the people think that it has closed its shops .though every body agrees itis the best .
i still feel the uranus I is their best designed speaker .

it is really nice to find so many of us (indians) around .
i am thinking of making a speaker based on a design by jeff mackaulay appeared in june 1995 of electronics world .
it is very compact and the design is very peculiar it has a 6th order alignment and because of its very small volume it exibits the character of a sealed box ie its output from the vent is still in phase with the speaker even below the resonance .
if you can give me any in put i will be glad .

regards ,
somak