I have been steadily building a moderately priced amplifier in Mumbai for the last year or so. I expect the whole system including source (PC with pro soundcard) to cost me in the region of 60-65000 Rupees after it's finished, and perform well ahead of its price range.
I've imported two dual mono LM4780 kits from Peter Daniel, a stepped attenuator and RCA plugs and sockets from Australia, and had a friend bring an E-mu 1212M as a source for this system from Singapore.
Total duty paid is zero so far.
Good quality EIs can be custom wound in Mumbai, at prices that are dirt cheap and they can be fully custom models (with oversized secondary wire, electrostatic shield, Mu-metal caps). May not be the prettiest, but they can stand a good shakedown with the best imports. A good 500 watt transformer should be within Rs. 1000 ($25?).
Toroids are also available, but their quality is not so great yet, they buzz and run hot (Mains filters are a must).
Thanks to Tarun (tcpip) I have contacted Dinrack, who is doing an awesome set of custom cases for me. The 2 cases cost me 11000 bucks, so it ain't cheap, but it's fully custom, with 5mm sandblasted aluminum throughout, and a very innovative method for weight support (the transformers weigh 6 kilos each, the total amp is expected to be in the range of 40 kios).
About heat, there is a strong point against Class-A for heat and power requirements, however it's not as if tube and Class-A amps don't sell in India, they do. Horses for courses.
The biggest problem with DIY Class A amps in India is finding heatsinks that can pull the heatsink off the device surface fast enough, not the Heatsink-to-ambient dissipation. The best heatsinks available from regular retail are just too wimpy for anything more than the OTA or the SEWA, and those devices I would hesitate to put on even the biggest heatsink available from Lamington Road (Which are what - 0.5 c/w?).
My little contribution to this thread.
I've imported two dual mono LM4780 kits from Peter Daniel, a stepped attenuator and RCA plugs and sockets from Australia, and had a friend bring an E-mu 1212M as a source for this system from Singapore.
Total duty paid is zero so far.
Good quality EIs can be custom wound in Mumbai, at prices that are dirt cheap and they can be fully custom models (with oversized secondary wire, electrostatic shield, Mu-metal caps). May not be the prettiest, but they can stand a good shakedown with the best imports. A good 500 watt transformer should be within Rs. 1000 ($25?).
Toroids are also available, but their quality is not so great yet, they buzz and run hot (Mains filters are a must).
Thanks to Tarun (tcpip) I have contacted Dinrack, who is doing an awesome set of custom cases for me. The 2 cases cost me 11000 bucks, so it ain't cheap, but it's fully custom, with 5mm sandblasted aluminum throughout, and a very innovative method for weight support (the transformers weigh 6 kilos each, the total amp is expected to be in the range of 40 kios).
About heat, there is a strong point against Class-A for heat and power requirements, however it's not as if tube and Class-A amps don't sell in India, they do. Horses for courses.
The biggest problem with DIY Class A amps in India is finding heatsinks that can pull the heatsink off the device surface fast enough, not the Heatsink-to-ambient dissipation. The best heatsinks available from regular retail are just too wimpy for anything more than the OTA or the SEWA, and those devices I would hesitate to put on even the biggest heatsink available from Lamington Road (Which are what - 0.5 c/w?).
My little contribution to this thread.
sangram said:
1. Good Torroids can be got from Miracle in Bangalore and they ship to Mumbai. OPTs for tubes are another question.
2. Why not use SS for the box it is stiffer. To support the tranny make a brass case it helps in shielding too!
3. Class A amps and Tubes do sell and so do Rs. 60K record players in fact the deealers I know cant keep them in stock. One person picked up to 85kg Krell amps in his Pajero. The dealer I know has one of these http://www.airsled.com/standard.htm
to move things around his shop. See in Mumbai (if not in India) things can get just as crazy as anywhere else. In fact I think he represents AirSled as an accessory line.
4. Heat is another matter anyone who can afford Krell or Tubes can afford (or budget for) adequate airconditioning as well. To hell with global warming and all that envirment stuff.
LOL.This thread was an hope for getting non magnetic MFRs for the JLH.
I have a tri amp which uses the Rod's active crossover playing through Philips India speakers, and was fine for me till this DIYAUDIO bug beat me. This amp contains 3 EI transformers of very high quality, salvaged from Mil-spec instrument. I also have components for 2 stereo amps, purchsed long back. But before I assembled them, I happened to stumble on this highly knowledgeable member's site called DIYAUDIO dot com and I started to hate these components.
I also have a pair of LM4780s.
Now the aim is not just assembling some amp but hearing those audio grade components.
I like listening to classical and want to experience it with Class A amp.
To make the long story short, to hear to these components, one needs at least good drivers. I would like to buy high efficiency driver like Fostex FE208. So has anyone in India ordered and received any drivers from Madisound, and what was their experience (read not of the drivers but customs etc.)
Gajanan Phadte
I have a tri amp which uses the Rod's active crossover playing through Philips India speakers, and was fine for me till this DIYAUDIO bug beat me. This amp contains 3 EI transformers of very high quality, salvaged from Mil-spec instrument. I also have components for 2 stereo amps, purchsed long back. But before I assembled them, I happened to stumble on this highly knowledgeable member's site called DIYAUDIO dot com and I started to hate these components.
I also have a pair of LM4780s.
Now the aim is not just assembling some amp but hearing those audio grade components.
I like listening to classical and want to experience it with Class A amp.
To make the long story short, to hear to these components, one needs at least good drivers. I would like to buy high efficiency driver like Fostex FE208. So has anyone in India ordered and received any drivers from Madisound, and what was their experience (read not of the drivers but customs etc.)
Gajanan Phadte
To be honest, I have only seen the last two pages of this thread and so have no knowledge of what all of you are collectively eyeing.
As Naveen pointed out Miracle in Bangalore sells torroids of a very high quality. I am a regular customer of Miracle. They don't give any discounts except for high quantity. Recently they hiked their prices thrice within two months. Even by my standards, I feel the prices are very high now. Nevertheless, I still buy from them. Someone wrote that a 500VA EI transformer would cost less than Rs.1,000/- in Mumbai; well, at Miracle you will shell out Rs.2,500/- give or take a hundred.
I imported a pair of Fostex 168ES Sigma drivers, one pair of Fountek JP3 ribbon tweeters, twenty 6.5" woofers, twenty dome tweeters, all of the crossover parts for these, long hair wool and a couple of other things. I had a tough time with the Customs department although right from the start I had stated that I was ready to pay the fully Duty. I ended up paying not only Duty but some demurrage to the warehouse, as well. I have receipts for all the payments made.
So be warned that if you get large quantities like I did, you will certainly end in trouble. Small quantities via air freight and particularly through a reputed courier company will save you many a sleepless night.
As Naveen pointed out Miracle in Bangalore sells torroids of a very high quality. I am a regular customer of Miracle. They don't give any discounts except for high quantity. Recently they hiked their prices thrice within two months. Even by my standards, I feel the prices are very high now. Nevertheless, I still buy from them. Someone wrote that a 500VA EI transformer would cost less than Rs.1,000/- in Mumbai; well, at Miracle you will shell out Rs.2,500/- give or take a hundred.
I imported a pair of Fostex 168ES Sigma drivers, one pair of Fountek JP3 ribbon tweeters, twenty 6.5" woofers, twenty dome tweeters, all of the crossover parts for these, long hair wool and a couple of other things. I had a tough time with the Customs department although right from the start I had stated that I was ready to pay the fully Duty. I ended up paying not only Duty but some demurrage to the warehouse, as well. I have receipts for all the payments made.
So be warned that if you get large quantities like I did, you will certainly end in trouble. Small quantities via air freight and particularly through a reputed courier company will save you many a sleepless night.
Hi Samuel
Sorry to hear about your unhappy experience with the government. Which is almost always the case with all our governemnt officials. I have a selfish motive though,
Which would be what? In absolute numbers or percentage of the driver costs?
Thanks again, sinceI am going to place a pretty large order I want to be mentally prepared for the tribulations...
Sorry to hear about your unhappy experience with the government. Which is almost always the case with all our governemnt officials. I have a selfish motive though,
Samuel Jayaraj said:
Which would be what? In absolute numbers or percentage of the driver costs?
Thanks again, sinceI am going to place a pretty large order I want to be mentally prepared for the tribulations...
I feel this Class A heat issue is being blown out.
All my amplifying devices are maasive-heating devices. Either Class A (whether MSOFET/Bipolar or Tubes). Heat/power drain has never been a factor – its just too marginal. I am more concerned about the gunk that comes in thro the electric supply and faithfully amplified by the Class A output devices – particularly the tubes.
Toriods are available from several sources. Miracle is one good source – I have one which was abandoned by George. DELTA makes some good toriodals and R Core too. I regularly use Toroidals made by a company called AE Electronics available in Chandni.
Secondly, heat sinks are a lot cheaper in India. You get wide variety too. Latly, we are now seeing Taiwanese heat sinks in the market. I hope the overall situation will improve with that.
OPTs, as Navin mentioned, are a different cattle of fish. I usually get mine from a small company in Korea who make very high standard stuff. Right now I;m building a pair of 845 monoblock and my last order to them was for a pair of 8k/120mA SE OPT’s. pair of 850CT-350CT-250CT, a pair of 10H PSU choke, pair of 175H Anode Choke and a pair of large filament transformers. The total came to approx 800US$. The lot weighed in at around 80Kg and came to India over several trips. If I had approached a company like Lundhal or Sowtar I would have been bank robbed. So a good deal but unfortunately not possible in India considering the small market. I know of guys in CAL who wind very good OPT’s plus they know their maths too. But the highly quality laminates and copper/silver alloy winding wires are not available here.
For Power tranny I can strongly recommend Delta. They have maintained their QC and offer stupendously wide range of them.
As for ordering from Madisound, I was contemplating a pair of FR’s. As luck would have it George was taking a vacation in the US and very kindly agreed to bring back a pair for me. I yet do not know what unmentionable things he wants in return But knowing him (and considering his age bracket) I am bracing my self.
All my amplifying devices are maasive-heating devices. Either Class A (whether MSOFET/Bipolar or Tubes). Heat/power drain has never been a factor – its just too marginal. I am more concerned about the gunk that comes in thro the electric supply and faithfully amplified by the Class A output devices – particularly the tubes.
Toriods are available from several sources. Miracle is one good source – I have one which was abandoned by George. DELTA makes some good toriodals and R Core too. I regularly use Toroidals made by a company called AE Electronics available in Chandni.
Secondly, heat sinks are a lot cheaper in India. You get wide variety too. Latly, we are now seeing Taiwanese heat sinks in the market. I hope the overall situation will improve with that.
OPTs, as Navin mentioned, are a different cattle of fish. I usually get mine from a small company in Korea who make very high standard stuff. Right now I;m building a pair of 845 monoblock and my last order to them was for a pair of 8k/120mA SE OPT’s. pair of 850CT-350CT-250CT, a pair of 10H PSU choke, pair of 175H Anode Choke and a pair of large filament transformers. The total came to approx 800US$. The lot weighed in at around 80Kg and came to India over several trips. If I had approached a company like Lundhal or Sowtar I would have been bank robbed. So a good deal but unfortunately not possible in India considering the small market. I know of guys in CAL who wind very good OPT’s plus they know their maths too. But the highly quality laminates and copper/silver alloy winding wires are not available here.
For Power tranny I can strongly recommend Delta. They have maintained their QC and offer stupendously wide range of them.
As for ordering from Madisound, I was contemplating a pair of FR’s. As luck would have it George was taking a vacation in the US and very kindly agreed to bring back a pair for me. I yet do not know what unmentionable things he wants in return
But knowing him (and considering his age bracket) I am bracing my self.I would have been happy if someone proved me wrong with his importing experience.
Looks like a $100 driver will cost around $400 at the door, that too with a great favour from .....
I better make a wish list and visit US, and stay near Madisound. Might endup cheaper
and without the tough time with the customs deptt.
Sangram, I am waiting for your outcome.
Please e-mail me at gmphadte@nio.org
Gajanan Phadte
Looks like a $100 driver will cost around $400 at the door, that too with a great favour from .....
I better make a wish list and visit US, and stay near Madisound. Might endup cheaper
and without the tough time with the customs deptt.
Sangram, I am waiting for your outcome.
Please e-mail me at gmphadte@nio.org
Gajanan Phadte
gmphadte said:
One pair of drivers should have no trouble except in handling. So be sure to ask Madisound to pack them and label them approriately. Remember insurance will only cover cost of product not shipping or duties and taxes.
On another topic I would suggest you consider a PP 167/168 instead. It will give you greater sensitivity, less beaming and 4 drivers can be later used for HT/AV if you ever go down that route or get better drivers (like I eneded up doing) and dont want to waste the fullrange drivers.
sangram said:
John K is an excellent Xo designer. Although I have not heard all of them I would recommend the fainthearted to just copy his designs. I dont think he has ever done a W22 based system.
Samuel Jayaraj said:
Miracle offers discounts only on orders above 1000pcs. And the discounts are 5-10%. Cant balme them copper prices have gone through the roof lately.
The 168ES is an excellent driver. Did you feel the need for the ribbon tweeter?
20 woofers and 20 tweeters? No wonder you had trouble I ti sbest not to import more than 5-6 of any one driver. I wold say if you are building a HT/AV system 5-6 woofers, 5-6 tweeters and 1-2 subwoofers would be the most you can expect to get away with without too many hassles. Still please use the services of a reputed importer/agency.
corbato said:
How are Delta for delivery. Miracle was great. i jsut emailed them and they sent the stuff COD.
I get my OPTs from Singapore. $150 for one that can be used with 2 EL 34 PP (UL taps included).
George when is you next vacation!
LOL Just kidding.
navin said:
No, this one http://seas.no/trym.htm done by Murray.
However I'm now leaning towards the smaller drivers, after stumbling on http://www.humblehomemadehifi.com/ which has some great series XO designs with the smaller Aluminum drivers, and without needing slanted baffles. I'm now not sure which to build, but I guess I'll make up my mind at some point.
I was planning on doing a blind copy first and then start tweaking it, actually.
No, not really, I'm not looking at full range for this particular set as I need content at both extremes (granted the smaller 2-ways don't deliver the bottom but in the nearfield that's not really a problem) for monitoring.
Maybe context helps.
I need compacts which will allow me to sit in front of the computer, and do some close-field monitoring. Right now there's a set of Altec Lansing speakers doing this and while they're basically OK for clipping checks, I can't rely on them for checking my mixes, they have too much at the two ends of the spectrum so mixes come out sounding hard and dry.
Full-ranges (at least from FR data) start late and roll off too early, so my mixes may then seem like they have a loudness filter built in. The best I have done is mixing only on floorstanders, but that's really tough given the acoustics of the room (Mumbai flat!).
The slightly rolled-off top octave of the TBFCG is just the ticket for close field, so it does not get too painful over long sessions. For the midbass I was thinking either the L15 or L18, now for the L18 I have two solid options to choose from - either the series XO + symmetric layout or parallel + offset layout.
However I am going to be building a set of full ranges for the bedroom, but that's for another time.
Maybe context helps.
I need compacts which will allow me to sit in front of the computer, and do some close-field monitoring. Right now there's a set of Altec Lansing speakers doing this and while they're basically OK for clipping checks, I can't rely on them for checking my mixes, they have too much at the two ends of the spectrum so mixes come out sounding hard and dry.
Full-ranges (at least from FR data) start late and roll off too early, so my mixes may then seem like they have a loudness filter built in. The best I have done is mixing only on floorstanders, but that's really tough given the acoustics of the room (Mumbai flat!).
The slightly rolled-off top octave of the TBFCG is just the ticket for close field, so it does not get too painful over long sessions. For the midbass I was thinking either the L15 or L18, now for the L18 I have two solid options to choose from - either the series XO + symmetric layout or parallel + offset layout.
However I am going to be building a set of full ranges for the bedroom, but that's for another time.
sangram said:
1. I would look at good coax drivers too. Tannoy and the USB project.
2. For close monitoring a 2 way (L15 or L18 dependin on how large you want the 2 way to be) is nicer. I would consider a series XO i possible. To my ears it sounds easier and when you are working for several hours you can do with less ear fatigue. atleast this is what I felt given the drivers I used.
3. what fullranges have you considered for your next fullrange project? I am tossing between the JX92, Foxtex 108 sigma, or a 2 way using the L12 (John K's design) as my box is limited to 10 liter or less. For my needs 80-20kz is adequate as I would have a couple of subs below that.
navin said:
I guess we're very badly off-topic, but here's the last one -
1. Yes I did consider the USB. Actually I'm not sure about the PP (soft) cone which is why I considered the Al cones.
2. John's L12? I didn't know he had an L12...
3. Actually I was looking at the Eminence Beta... J/K. And it'll be my first fullrange. I was looking at the Aura NS3/4 or TB titanium drivers, or maybe I'll plump for the FF125K. This is a bedroom background music
project so size is a major consideration.
I usually buy from their dealer 'Radio Products of India' in Kolkata. Now this man is in business since 1938 in the same shop. At age 93 he is as sharp as ever. A great repository of tube related wisdom and a crazy nerd who open his shutters just to keep himself occupied. Although I have an option of buying direct from Delta, I prefer supporting the old man.navin said:
DELTA will send by courier. Check their range at http://deltatransformer.com . They are email and cell phone friendly. Call Mr. Harish Arora at 9871050709. You can give my reference.
Some of their vintage Trafos are not listed in the website. But I have a copy of their mid-70's catalogue for valve amps and I get my trafo within a fortnight. They also make audio output transformers. I will be happy to send a scan if needed.
After using several cheaper (but lousy) options I have come back to DELTA. My only grouse is that they don’t do really HV like 1KV and up.
Back on topic.
Some nice finds.
There is a PCB maker on Lamington Road who gave me a first quote of 1.50 per sq. cm. for Double sided PTH boards, and a Rs. 200 charge for the films. If you guys actually can decide which amp to build, this might be the easiest way out.
1/8 watt Metal films resistors are available in bulk (100 and multiples) at .40 paise each. They're not too bad - and I don't know if resistors have a sound. You can also import exotics if you need to. 1/4 watt metal films are now very common, these smaller ones help make a build very compact.
Chips will need to be imported but even 100 chips make for a small package. Digikey has all the chipamps ever discussed on this forum in stock, and good prices for 100+ quantities.
Big capacitors are very easy to find and not expensive. Elna (not the audio ones) computer-grade caps of 10,000uF/71 volts - 10 for 750 bucks, not too bad. Slightly higher price for single units.
Chassis are still a problem, would love to hear from others what they are doing.
I had thought of a modular system using L-angles and Alu sheets in precut formats, available in 5" and 10" depths (to match the running length of commonly available sinks). However if it is a group buy it would be easier to organise a large quantity of a single type of chassis.
So here is what I propose:
A group chip amp project based on LM4780. This balances the need of power, economy and fidelity within a reasonable cost, and is a good initiation into hifi.
My proposition is the use of two LM4780 chips per 'side'. Each 'side' will be capable of stereo, parallel or bridge operation with the use of only a single XLR socket and no switches (provided you have a bridging adapter to invert the polarity to one half of the 4780). This is tremendously flexible to adapt to a situation with low-impedance, high-impedance, difficult and easy speaker loads.
The power supply will need to be kept at 30 volts or so to stay within safe area for operation into 4 ohm loads or bridged modes. 2 ohm loads will need parallel operation only, and since it's 4 amplifiers, multi-room applications are also possible.
Two sets of binding posts are required, so four pairs total. Input will be XLR panel sockets, and mains will be fed through IEC sockets on the back panel.
The design will be pure dual mono, but designed around the more common Center-tapped transformer with single bridge rectifier. You could use a single large transformer if you wish.
The PCBs will need to be designed. Someone come up with that please. Ideally a double sided PTH PCB. A regular datasheet-based stereo application with room for an output resistor is all that's needed, so if anyone raises their hand we can get this off the ground.
The chassis will need to be designed, I can take that part on in consultation with Dinrack if there's enough interest (20 pieces). I expect the cost limit to be around Rs. 2000-2500 if you don't go overboard (which means no 8 mm front panels). These should be able to be shipped flat and hand-assembled in a few minutes, so that can be part of the design brief.
Part sourcing: We'll need someone to source parts. Since most of us have productive and remunerative day jobs, this will need to be done on weekends.
Caps and resistors can be sourced from one point to get rate benefits.
Transformers are very heavy and everyone will have their own preferences, so I guess localised sourcing is better.
Heatsinks: It would mke sense for the heatsinks to ship with the chassis if they are designed as a single unit, however they add weight (and bulk).
Case hardware: MX has a decent range of sockets, plugs and case hardware and their plating has improved dramatically. These should be available locally but we will need to account for specific input, output and power sockets on the back panel at the design stage itself.
I guess we should cut off at 20 units, so let's start taking votes. I don't need one myself, but I will take one. So that's 19 more, then we can start getting some more details down.
Some nice finds.
There is a PCB maker on Lamington Road who gave me a first quote of 1.50 per sq. cm. for Double sided PTH boards, and a Rs. 200 charge for the films. If you guys actually can decide which amp to build, this might be the easiest way out.
1/8 watt Metal films resistors are available in bulk (100 and multiples) at .40 paise each. They're not too bad - and I don't know if resistors have a sound. You can also import exotics if you need to. 1/4 watt metal films are now very common, these smaller ones help make a build very compact.
Chips will need to be imported but even 100 chips make for a small package. Digikey has all the chipamps ever discussed on this forum in stock, and good prices for 100+ quantities.
Big capacitors are very easy to find and not expensive. Elna (not the audio ones) computer-grade caps of 10,000uF/71 volts - 10 for 750 bucks, not too bad. Slightly higher price for single units.
Chassis are still a problem, would love to hear from others what they are doing.
I had thought of a modular system using L-angles and Alu sheets in precut formats, available in 5" and 10" depths (to match the running length of commonly available sinks). However if it is a group buy it would be easier to organise a large quantity of a single type of chassis.
So here is what I propose:
A group chip amp project based on LM4780. This balances the need of power, economy and fidelity within a reasonable cost, and is a good initiation into hifi.
My proposition is the use of two LM4780 chips per 'side'. Each 'side' will be capable of stereo, parallel or bridge operation with the use of only a single XLR socket and no switches (provided you have a bridging adapter to invert the polarity to one half of the 4780). This is tremendously flexible to adapt to a situation with low-impedance, high-impedance, difficult and easy speaker loads.
The power supply will need to be kept at 30 volts or so to stay within safe area for operation into 4 ohm loads or bridged modes. 2 ohm loads will need parallel operation only, and since it's 4 amplifiers, multi-room applications are also possible.
Two sets of binding posts are required, so four pairs total. Input will be XLR panel sockets, and mains will be fed through IEC sockets on the back panel.
The design will be pure dual mono, but designed around the more common Center-tapped transformer with single bridge rectifier. You could use a single large transformer if you wish.
The PCBs will need to be designed. Someone come up with that please. Ideally a double sided PTH PCB. A regular datasheet-based stereo application with room for an output resistor is all that's needed, so if anyone raises their hand we can get this off the ground.
The chassis will need to be designed, I can take that part on in consultation with Dinrack if there's enough interest (20 pieces). I expect the cost limit to be around Rs. 2000-2500 if you don't go overboard (which means no 8 mm front panels). These should be able to be shipped flat and hand-assembled in a few minutes, so that can be part of the design brief.
Part sourcing: We'll need someone to source parts. Since most of us have productive and remunerative day jobs, this will need to be done on weekends.
Caps and resistors can be sourced from one point to get rate benefits.
Transformers are very heavy and everyone will have their own preferences, so I guess localised sourcing is better.
Heatsinks: It would mke sense for the heatsinks to ship with the chassis if they are designed as a single unit, however they add weight (and bulk).
Case hardware: MX has a decent range of sockets, plugs and case hardware and their plating has improved dramatically. These should be available locally but we will need to account for specific input, output and power sockets on the back panel at the design stage itself.
I guess we should cut off at 20 units, so let's start taking votes. I don't need one myself, but I will take one. So that's 19 more, then we can start getting some more details down.
gmphadte said:
I meant Push-Push Fostex 167 or 168. There are plenty of Fostex 167/168 designs on the net. The advantage of push-push esp if you have room for this sort of design is that you dont need baffle step compensation. And with 2 drivers you can get plenty loud too!
corbato said:
Do they make decent OPTs too. I thought you imported your OPTs.
I would like to see what Delta quotes. Right now I am happy with Miracle and they are cheaper than my older Mumbai supplier!
sangram said:
1. What amp are we building here. I am no clear. Once we have that settled making the PCB is the easy part.
2. Once you have an amp and about 20-30 takers you can get most things on lamington road. parts not available can be imported in one lot. but who's co-ordinating this project. If parts need to be imported who will do the honours. Importing can be a hassle.
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