Parts in Mumbai (India)

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ashok

ashok

Member
Joined 2002
vkj said:
Another audio question: Is it possible to send digital audio (from say a DVD player) over long distances (~20 feet) via 75 Ohm cable and do the D-A conversion at the far end?

vkj
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Use BNC connectors and genuine 75 ohm video cable. I think Neutrik has 75 ohm RCA type connectors but would be quite expensive and harder to find.
Regular RCA connectors are not 75 ohm and you could have quite a bit of loss there. Safest is to stick to BNC as you get good quality BNC connectors in the market.
You can find that many audiophiles have pulled out the RCA SPDIF output connectors on their players and replaced them with BNC sockets and usually not just because they want to take the signals over longer distances.
 
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V

vkj

Member
Joined 2011
linuxguru said:
Liquid flux is a recent innovation, and generally meant for wave-soldering or hand soldering on plated surfaces in current use - Sn/Pb, lead-free, immersion silver or gold. It works great on clean uncontaminated surfaces, and produces shiny, concave solder beads. It's really mainly meant for solders to flow very smoothly and wet surfaces.

For terribly contaminated copper surfaces (with lots of oxide and other metallic impurities like aluminium, iron, etc.), ammonium chloride aka Sal Ammoniac was the only easily available flux that worked in the old days. It's a white slightly hygroscopic salt that used to be available from chemistry supply stores. It's harmless and non-toxic in solid form, but produces an acrid cloud of ammonia and hydrogen chloride at the moment of soldering. I don't know if Mangaldeep's aluminium flux is the same thing, but sal ammoniac works with some difficulty on aluminium surfaces also.



The spectacled guy in the same row of shops as Mangaldeep (the enamelled Cu wire store) is the Watts dealer and specializes in resistors. You can ask specifically for Watts and maybe a few other local brands from him. Most other shops will also give you Watts on request, but they source it mostly from the spectacled guy above. It's clearly marked on the paper tape, so there's no hanky-panky. The leads will be very soft tin-plated pure copper on almost any Watts resistor, except on some older stuff where they used tin-plated brass.

The problem with the cheap resistors is ferromagnetic leads or end-caps. The worst are those Fe-Cu (Fecuma) leads seen on cheap metal-oxide resistors, but nickel/kovar plating is also weakly magnetic and messes up audio.

Weakly magnetic end-caps now seem to be an unavoidable evil, even on otherwise high-quality imports like Panasonic ERX metal film and KOA CF carbon film. There are very few resistors now that are completely non-magnetic - Dale, PRP, Futaba, NOS Holco, Welwyn and some Shallcross non-inductive wirewounds come to mind. Of these, Dales are the only ones that occasionally show up locally.



I have one of those Rs.100 Chinese MP3 modules with remote as well.
I haven't tried it yet, just wanted the little IR remote actually.

For high-quality digital playback, the best options are moderately expensive: A linux-based Atom motherboard connected to a separate USB 2.0 audio DAC like the HiFiMeDIY Sabre ES9023 24/96 DAC.



Sure, you just need a DVD player with digital SPDIF coax output, and a DAC or an amplifier with SPDIF digital input. Many DVD players have SPDIF built-in, and some have optical output as well.

There are inexpensive modules that can convert the optical signal back to coax SPDIF digital, or slightly more expensive modules that have a DAC and can convert optical to 2-channel line-level analog audio.

The simplest option is any cheap Home Theatre receiver that has digital input - just about any Sony, Pioneer, Kenwood, Panasonic, Harman-Kardon, etc.
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Thanks for the info, Linuxguru. I was under the impression that Amm. Cl. was a no-no for electronics. I remember in the old days when brass vessels were coated with lead and this was liberally used by the fella with that most interesting bellows who used to set up a furnace right on the road side! Eating all that lead has given me a very good excuse for my insanity tho :).

The Al. flux is prob. Amm. based, its liquid tho and is quite corrosive. For ~Rs 200 I sure hope it isnt just Amm. Cl.

Its really quite incredible that this Chinese manuf. can produce a MP3 board PLUS a remote for peanuts, literally. It just doesnt make sense. I was so excited that I bought two :(. Unlike that pathetic Sony 660P DVD player, it handles NTFS flash-drives too! If it wasnt for that popping noise, it would be quite decent, actually.

If I recall some of the Microchip processors have a built-in USB support. Not sure if they have the HP to do the MP3 tho. The Microchip website has a section on MP3 apps. but it appears to be mostly for low-quality voice.

I have a stand-alone DAC, a small, but expensive unit made by Audio Alchemy. Tho it claims to be a audiophile type, with those thick gold plated Monster Cable audio outs, I was a bit surprised to find a very ordinary Cirrus Logic run-of-the-mill DAC chip (forgot the no.). I was hoping to press this into service for the remote amp.

I dont have an AV recr. I made a 5-ch PA (Leach) and bought a Proton Preamp way back (the co. is out of business now, and with good reason--another ripoff). The latter has developed an intermittent distortion on the center channel, and I am unable to fix it.

vkj
 
V

vkj

Member
Joined 2011
ashok said:
Use BNC connectors and genuine 75 ohm video cable. I think Neutrik has 75 ohm RCA type connectors but would be quite expensive and harder to find.
Regular RCA connectors are not 75 ohm and you could have quite a bit of loss there. Safest is to stick to BNC as you get good quality BNC connectors in the market.
You can find that many audiophiles have pulled out the RCA SPDIF output connectors on their players and replaced them with BNC sockets and usually not just because they want to take the signals over longer distances.
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Thanks. Can you explain why BNC is required? AKAIK, unlike in (analog) video, the SPDIF signal isnt 75-ohm terminated? I would imagine that one uses the coax simply to minimize cap. loading. Im guessing the difference between a cheap coax and good coax cable in terms of cap. isnt that much? I would certainly agree for 75 Ohm applications, resistive loading would contribute to reflections, and hence here a good coax is important. Right? or am I missing something?

vkj
 
Roushon

Roushon

Member
Joined 2004
gannaji said:
I am a regular reader of this thread. Glad to note that DIY activity is very live in india.
Can I request that when a source for an item is mentioned, the contact details may also be given like t el no and url if exists. This will help non bombayites also to contact the parties.
Gannaji
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This was the main purpose of this thread and it is systematically maintained. Please check back postings, wherever source of parts are given, all details are mentioned. I am grateful to all the contributors. A page was also created by Aucosticraft.

https://docs.google.com/spreadsheet/ccc?key=0AmUCTMjsBdd4dHY3UkJSOGllQl8wSkZUQUpueTF1X3c#gid=0

You can also contribute to this page by clicking the below link.

https://docs.google.com/spreadsheet...ue&formkey=dHY3UkJSOGllQl8wSkZUQUpueTF1X3c6MQ

Edit: The above page does not yet contain all the informations posted in this thread.

Roushon.
 
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Roushon

Roushon

Member
Joined 2004
A request!

I was just reading some few back pages and was happy that people also discuss about parts and their availability. But noticed these discussions are pointed towards persons who are aware of the local market and names of the retailers.

My request to all the posters that whenever you mention the name of a particular retailer please give full details, like full name, full address and phone numbers and then you can continue your discussions.

In case you are only interested in discussion then please open a new thread with the correct thread name, that will give more exposer to your subject and at the same time protect the purpose of this thread.

Thanks and regards
Roushon.
 
A

Aucosticraft

Member
Joined 2009
Roushon said:
I was just reading some few back pages and was happy that people also discuss about parts and their availability. But noticed these discussions are pointed towards persons who are aware of the local market and names of the retailers.

My request to all the posters that whenever you mention the name of a particular retailer please give full details, like full name, full address and phone numbers and then you can continue your discussions.

In case you are only interested in discussion then please open a new thread with the correct thread name, that will give more exposer to your subject and at the same time protect the purpose of this thread.

Thanks and regards
Roushon.
Click to expand...

May I add , Pls update the sheet too.
 
Roushon

Roushon

Member
Joined 2004
I need to order Panasonic FM series 1000uF 50v
capacitor from Elements 14-kits-n-spares (Mft. part
no.EEUFM1H102, Elements14 part no. 1219484)) .

Shopping.kitsnspares.com

Up to 49 the cost is Rs 107/- and from 50-99 it is Rs 73/-.
A drastic drop. I need about 20 to 25 pieces. If any of you
need, kindly let me know then we can order a large
amount. Shipping cost of a lot of 50 caps is Rs 300/- and
then a separate shipping cost will be from me to you.

Thanks
Roushon
 
L

linuxguru

Member
Joined 2007
I'd be vary about sinking too much cash into average-quality electrolytics like the Panasonic FM, with its magnetic leads and aqueous electrolyte - they're really computer/industrial grade low-ESR caps, rather than audiophile grade (of which there are very few: Rubycon Black Gates, Elna Silmic/Cerafine/Tonerex/Starget/Duorex, Panasonic Pureism/Takeh, Nichicon Muse (over half dozen in the series), Sanyo OSCON, Nippon Chemicon AWF and a few others. All of these have non-magnetic leads and construction.

A simple test is this: If the leads are ferromagnetic, they're not good enough for demanding audio, but may still be OK for high-current bypass and decoupling applications. There are a zillion commodity electrolytics that fall into this category, including inexpensive Nichicon P-series, Nippon Chemicon K-series, and Rubycon Y- and Z-series. In fact, nothing beats a Rubycon ZL or ZLH if you're willing to live with magnetic leads.
 
ashok

ashok

Member
Joined 2002
vkj said:
.... Can you explain why BNC is required?

vkj
Click to expand...

SPDIF is 75 ohms terminated. Everything in the chain from the chip output to the reciever input must have a characteristic impedance of 75 ohms. EVEN the connectors. IF this does not happen you get reflections. If your system can tolerate ordinary RCA sockets and plugs and you cannot hear any problems due to jitter in your system then you can just stick to that . There is always an ideal goal. But you can often get away with imperfections in your system. If your ear is happy , that's all that matters.

I tried to write a longer explanation on this but it took too much time just to get part way. So I googled and found a write up by Steve Nugent which explains it very well. Read it.
spdif

Cheers.
 
Roushon

Roushon

Member
Joined 2004
linuxguru said:
I'd be vary about sinking too much cash into average-quality electrolytics like the Panasonic FM, with its magnetic leads and aqueous electrolyte - they're really computer/industrial grade low-ESR caps, rather than audiophile grade (of which there are very few: Rubycon Black Gates, Elna Silmic/Cerafine/Tonerex/Starget/Duorex, Panasonic Pureism/Takeh, Nichicon Muse (over half dozen in the series), Sanyo OSCON, Nippon Chemicon AWF and a few others. All of these have non-magnetic leads and construction.

A simple test is this: If the leads are ferromagnetic, they're not good enough for demanding audio, but may still be OK for high-current bypass and decoupling applications. There are a zillion commodity electrolytics that fall into this category, including inexpensive Nichicon P-series, Nippon Chemicon K-series, and Rubycon Y- and Z-series. In fact, nothing beats a Rubycon ZL or ZLH if you're willing to live with magnetic leads.
Click to expand...

Thanks for the info. But I read otherwise on the net and in many other threads here....everybody points me to Blackgate, Panasonic FM and Elna Silmic II. Of which first one is either not available or costs a fortune and the last one is suggested for signal paths. I needed something for power supply which is just after BG. Will search for Rubycon ZL or ZLH as you say. Could you tell me where can I find them (physical shop) genuine in India? Please do not say search in Lamington Road. Something
specific.

Regards
Roushon.
 
Sangram

Sangram

Moderator
Joined 2002
Paid Member
^^I bought a hundred each of 100uF FM and a few values of FC about 6 years ago. I can testify that the FM is not great in signal coupling application in series path. However it is *very* good as a decoupling cap and does not require paralleling of low-value caps in audio applications most of the time. Also, when used as a Ci cap it has an interesting sonic signature, very different from the regular audiophile caps (and I have used plenty).

I agree though that investing in 100 of them may not be such a fantastic idea unless you're certain you will be using at least half that number over the next few years.
 
Roushon

Roushon

Member
Joined 2004
sangram said:
^^I bought a hundred each of 100uF FM and a few values of FC about 6 years ago. I can testify that the FM is not great in signal coupling application in series path. However it is *very* good as a decoupling cap and does not require paralleling of low-value caps in audio applications most of the time. Also, when used as a Ci cap it has an interesting sonic signature, very different from the regular audiophile caps (and I have used plenty).

I agree though that investing in 100 of them may not be such a fantastic idea unless you're certain you will be using at least half that number over the next few years.
Click to expand...

Thanks for the kind information from your own experience. I did plan to order 50 of them (1000uF 50v)
and use them in my whole system (amp, players, preamp etc etc). Just was searching for the other caps suggested by Linuxguru, they are far more expensive and I do not read about them much, do not know why?

Regards
Roushon.
 
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