Equipment Mods

Autor

Beitrag

Manek
Inventar

#1 erstellt: 24. Mai 2008, 17:12

Hey guys

Any of you know of people who do good mods to stock equipment like cdp's, amps, even xovers ?

I am thinking there ought to be someone who does this.I am talking serious stuff and not replacements of stock chords with iec sockets :-)

I also wonder how many of us would be open to modifying the equipment we own ?

Manek

reignofchaos
Stammgast

#2 erstellt: 25. Mai 2008, 06:42

My DAC is modified heavily... replaced caps, higher precision TXCO clock, modified headphone out stage with LM4562 opamp. All done my yours truly :).

Manek
Inventar

#3 erstellt: 26. Mai 2008, 12:04

great...!

but for people who are a bit electronically challanged....what do we do sir ?

manek.

reignofchaos
Stammgast

#4 erstellt: 02. Jun 2008, 20:22

It depends on the CD Player/DAC. Search on the net for mods for the particular model. Get the parts either locally (or rs-india) or from digikey or partsexpress. Then start off one at a time. Do not attempt too many mods at the same time.

Thats about all I followed.

Arj
Inventar

#5 erstellt: 03. Jun 2008, 00:57

manek, which component are you planning to get modded ? not sure if there are knowledgeable people who do it in india ! an Audiophile + DIY enthusiasts who has the time is not very common !

Manek
Inventar

#6 erstellt: 03. Jun 2008, 06:21

hi arj,

I may try and experiment with my nad 320bee or even the 521i cdp. But only if I find reliable people who do it and know what they are doing :-)

I just want to know how far can you push these stock designs.....with prices rocketing on all fronts it may not be a bad option.

I know you got your nad modded....

Manek.

abhi.pani
Inventar

#7 erstellt: 03. Jun 2008, 07:26

Hi Manek,
Just a suggestion...since Arj's Modded CDP is there in Mumbai, why dont you compare your stock CDP to it and post some impressions, it will be nice and enlightening

Manek
Inventar

#8 erstellt: 03. Jun 2008, 08:00

yes good idea

but for all who want to try modding....make sure you keep the copies of the service manuals.

Manek.

reignofchaos
Stammgast

#9 erstellt: 03. Jun 2008, 09:15

Manek schrieb:

For the 521BEE, the easiest and the most beneficial mod probably is replacing the NE5532 opamp in the output stage with an LM4562. This is basically a free upgrade if you have the requisite soldering skills. One can get free samples from National Semiconductor. Once you receive the sample, its simply a matter of desoldering the existing opamp and soldering the new one. The next stage would probably be a clock upgrade followed by recapping. Anything beyond that would require significant expertise.

I'm not sure of amplifier mods. Never really tried it. Source mods definitely are the most bang for the buck.

Manek
Inventar

#10 erstellt: 03. Jun 2008, 09:43

thanks reign.....I have the nad 521i and not the 521bee.

my stuff is in pune so when I get there next will plan.... but wanted to do a POC on my stock pioneer DV-366 dvd player and then move ahead....

the DVD player albeit old still plays perfectly....

What do you suggest for it ? opamp ? PS caps ?

Manek.

reignofchaos
Stammgast

#11 erstellt: 03. Jun 2008, 11:28

Manek schrieb:

I think even that one uses a very similar output stage and will definitely benefit from an opamp upgrade. Recapping doesn't bring benefits worth the cost IMHO. Blackgates are just way too expensive.

Arj
Inventar

#12 erstellt: 03. Jun 2008, 12:08

Manek,
the NAD designs are not much amenable to modding. there is only so much you can improve.
typical changes which i had got done were
1. OPAMPS and input diodes
2. Remove Muting capacitor
3. Bias output stage to class A.

the 521i and the 521BEE do have some design changes and do sound diufferent..i do have a service manual for it somewhere..can send it to you if required.

but better bang for the buck would be upgrading it to a better cdp

[Beitrag von Arj am 03. Jun 2008, 12:28 bearbeitet]

audio_engr
Ist häufiger hier

#13 erstellt: 03. Jun 2008, 17:26

As the previous poster had mentioned, you can improve your NAD C-521i in the following areas under-mentioned:

1. Replace power diodes D514, D515, D516 & D517 with 3 ampere type so that the motor gets more current that is already starved of current, hence takes a long time for mechanism operations & tracking.

2. Replace Cap C529 3300uF/16V with 10,000uF/16V.

3. NAD in their Service Supplement suggested to replace:
C122 to 2.7pF
C123 to 0.01uF
C124 to 22pF

Reason: NAD said: If the customer has a complaint about C-520/521/521i/522/524/540/541/541i CD Players not being able to play a CDR or out of tolerance discs, try replacing these capacitors with the following values. This will also provide a cure on some players for “NO DISC” message.

4. Now, you may want to replace the analog stage Op-Amps U305 & U306 Dual Opamp with something exotic. Tried BB OPA627 Single opamp on a Brown-dog adapter and the result was extremely good but proved far too expensive for such a player. BB OPA 2107 (Dual) for the U305 & 306 is 90% of OPA627's performance.

5. Class-A biasing of Opamps: I ran them at 7.5mA into Class-A bias using appropriate resistors between pins (4 to 1) and (4 to 7). The sound was much meatier, organic, lush high freq, much more open, more midrange info cum overall transparency, etc. etc. Try it but opamp may require some DIY heatsink on top of the IC to cool it down. (After all, we live in India - a climatically hot country).
[This treatment is per Dual Opamp]. In the NAD, there are 2 of them.

Problem with these series of NADs is that the Sanyo transport is poor and lets down the player.

Advice: You may do 1, 2, & 3 together. Take up 4 later and then finish the 5.

Cheers! Have Fun.

Manek
Inventar

#14 erstellt: 03. Jun 2008, 18:40

Hi arj, audio engr

Tks for the updates. I am sure to buy a new player if and when I need one. No question about that. I am curious to know what modded players can do over stock, that's all.
Always read stuff on internet, never found out.

Manek

bhagwan69
Inventar

#15 erstellt: 03. Jun 2008, 20:01

Manek schrieb:

I also wonder how many of us would be open to modifying the equipment we own ?Manek

Not me;
I would not like to modify any gear that is owned by me. In fact, I would not like to have it opened at all !!!

audio_engr
Ist häufiger hier

#16 erstellt: 03. Jun 2008, 20:24

Mods are not everybody's cup of tea - only the tech competent with a flair to tailor & customize to their needs bother with this. You'll be surprised that even the 2 lac CDP uses a $5 opamp in a critical section whereas they should have implemented 627s or discrete.

bhagwan69
Inventar

#17 erstellt: 04. Jun 2008, 04:44

audio_engr schrieb:

Perfectly said;

CD Players cost 5 to 8 lacs too. Now, they too use the same 1 $ to 10 $ components. It is not about what is used, but how it is used. I suppose, if it was so easy, then ever CD Player maker would modify his CD Player with 50 $ parts & raise his CD Players price by 500 $'s and sell it in the market.

My point being, every designer has a 'limitation' [intelectual] i.e.
If it was so easy, every tube amp maker would make the Audio Note 'Ongaku' !!! But they cannot, there fore there is 1 Audio Note [Japan] & 1 Fake Audio Note [UK] !!

Basically entry level gear - sub US $'s 500/- may have a lot of chance to be 'modded' as 'audio engineer' states. But High End Gear; I am not so sure........
Can an EMM Labs / dcS / Teac Esoteric / Meridian etc. be Modded ? I am not so sure......

Manek
Inventar

#18 erstellt: 04. Jun 2008, 05:49

Audio engr and bhagwan

You both have very valid points.

Now here is a simple thought....is there budget kit which is well designed but with cheaper parts to keep costs down....if so couldn't component replacement mods do the trick to raise it a bar or two ?
If so which one ? Maybe we could take a hint from the modders who do this for a living ?

Manek

Arj
Inventar

#19 erstellt: 04. Jun 2008, 08:04

Manek schrieb:

manek, i guess the Zhou Lou, Lite Dac etc are like that which can be modded for much higher value.
in mps the gainclone clones and the AKSA kit etc come first to mind.

I belive there also are PAss Labs schematics/kits available ? not sure of it though

audio_engr
Ist häufiger hier

#20 erstellt: 04. Jun 2008, 17:41

Can an EMM Labs / dcS / Teac Esoteric / Meridian etc. be Modded ? I am not so sure......

The above brands execute whatever they put in well - even if its a $1 part. Upon opening the top cover of these brands, the overall topology of their circuit is such that there's practically no scope to improve much. Moreover, tinkering them often results in messing up. Best, leave them alone & if unhappy, move on to something else.

Its the low value stuff that can be pushed up - depending on the circuit and its execution. Sub $1000 products esp. dacs & CDP's dac stages usually has room for improvement. The manufacturers usually skimp here in order to keep costs in check. Sometimes they could be simple stuff like better connectors - RCA sockets or coax ones.

Thoroughbred manufacturers will not leave scope in such areas. They'll make doubly sure its done correct.

There are an handful of Chinese gear at sensible prices (dacs, CDPs and tube amps) where couple of critical parts put in are cheap and substitution can honestly boost performance. Yet the build quality is fairly nice. e.g. Shangling CDPs.

bhagwan69
Inventar

#21 erstellt: 04. Jun 2008, 18:25

audio_engr schrieb:

Can an EMM Labs / dcS / Teac Esoteric / Meridian etc. be Modded ? I am not so sure......

Precisely so;

Even 'expensive' machines use cheap and common parts. The money is not for the parts, but for the 'way they are used' !!! The money charged is for the R & D / trial & error that has gone into making the product.
More often than not, they are sitting on cutting edge technology.

sivat
Stammgast

#22 erstellt: 05. Jun 2008, 06:21

Manek schrieb:

Why don't we wail until Amp_Nut gets his "buffalo" (love the name) DAC ... Get the DAC ...and add a tube output stage (thought u might need a transformer to convert that balanced output from DAC into single-ended input for the valve output stage).

Based on experience, i will generally stay from any Chinese products.

If u can spend a little extra get the DAC module from Hagtech.

Regards
Siva.

Amp_Nut
Inventar

#23 erstellt: 05. Jun 2008, 09:29

Siva,

It looks like its going to be a long wait ( 6 to 8 weeks ? )

The site received only 20 of the DAC chips, and it seems that there is a LOOOONG wait list ...

On yr pointer towards the Hagtech... its price similar ( US $ 550 As a Kit ) to the Eval board that you are using ... and I guess the Hagtech is inferior ?

sivat
Stammgast

#24 erstellt: 05. Jun 2008, 13:48

I have both the modules (eval and hagdac). Both are equally good.

Eval Board : Gives u the flexibility with filters, choice of I/V resistors, etc., You will have to buy the oscillator

HAGDAC : Unless u are good with SMD components, u will loose the above mentioned flexibility. Oscillator comes with the board.

I will highly recommend HAGDAC if you are looking at just screwing it up into ur box without much R&D. If you like to fool around, then Eval board will be better.

If you were in BLR, you could have listed to both....

Amp_Nut
Inventar

#25 erstellt: 05. Jun 2008, 14:00

Thanks for the info & and the invite !

I presume you are referring to the CHIME HAGDAC ?

Or did you buy only the HAGDAC ( Without O/p tube buffer, PSU, Volume Control & Chasis ?

Thanks again for sharing your extensive experience..

sivat
Stammgast

#26 erstellt: 05. Jun 2008, 14:16

I got only the HAGDAC module....the output stage is different. Since the module had a very low I/V, i used a step up transformer before the tube o/p stage.

Volume control is done in the preamp with a TVC.

Chasis is the same one i had used for the Eval board...

Amp_Nut
Inventar

#27 erstellt: 05. Jun 2008, 14:31

Thanks for the details, Siva.

I see that the HAGDAC does not do 24/96 ?

sivat
Stammgast

#28 erstellt: 06. Jun 2008, 05:49

Amp_Nut schrieb:

Thanks for the details, Siva.

I see that the HAGDAC does not do 24/96 ?

On the eval board, i tried both 20 and 24 bit operations between the receiver/filter and the PCM1704. I preferred the 20 bit....all though it is a very very negligible difference.

I'm not very sure whether 24/96 will be an advantage or disadvantage. I would keep the filtering operations as simple as possible...which is kind of a mid-way position between the Non-OS and OS camps..

Amp_Nut
Inventar

#29 erstellt: 06. Jun 2008, 08:02

Hi Siva,

I was looking into 24/96 playback capability, not so much for upsampling, but playing back Hi Res ( 24/96) Music Downloads, thru a HDD.

A USB interface is now, an Essential feature for me, for any DAC that I buy.

Incidentally, recently downloaded 6 Chesky's Songs, currently on offer as free downloads ( 24/96) ...

reignofchaos
Stammgast

#30 erstellt: 06. Jun 2008, 09:45

Which website was this that's offering 24/96 content for free :KR.

Amp_Nut
Inventar

#31 erstellt: 06. Jun 2008, 11:50

http://www.hdtracks.com

The 8 Free 24/96 Traccks offered for download are :

Our Turn to Dance - Livingston Taylor
Well, I've Been to Memphis - David Johansen and the Harry Smiths
Mexican Hat Dance - Earl Wild
Larger Than Life - Holly Cole
Rumble - Mike Garson
Can't Let Go - Koko Taylor
Baba Yaga - The Minnesota Orchestra/Eiji Oue
Una tarde de verano - Brio

Includes complete PDF liner notes and cover art. Plus, your choice of FLAC, AIFF or MP3 high resolution files.

Amp_Nut
Inventar

#32 erstellt: 06. Jun 2008, 11:53

From Audiogon's Industry News ( Also similar reports on Stereophile )

http://cgim.audiogon.com/cgi-bin/pr.pl?cheskyrecords&1211395266&v

05-20-08 Chesky Records

Chesky launches HDTracks with free hi-res download

New York City, May 20, 2008 – HDtracks.com, the new high-resolution digital music store founded by audiophile record label Chesky Records, today announced the limited availability of a free album download that encourages all listeners to “hear the HDtracks difference.”

“The HDtracks Ultimate Download Experience,” free to visitors to HDtracks.com who register with only an email address, offers eight spectacular audiophile-quality recordings across different genres, all hand-picked to prove just how great music downloads can sound. Those who download The Ultimate Download Experience will also receive a promotional code for 20% off their next HDtracks purchase.

HDtrack is unique among digital music stores for its combination of CD-quality music files unencumbered by digital rights management (DRM)*, the ability to download in any of three file types to match most playback devices, and a reliable, easy-to-use interface that makes browsing and downloading a pleasure. The site features thousands of artists representing 60 of the world’s best independent record labels, and all albums are priced at $11.98 and come complete with PDF liner notes (a first among digital music sites). Tracks may be downloaded as CD-quality uncompressed AIFF files or lossless FLAC files, or MP3 files ripped at 320 kilobits-per-second (kbps) — some 2½-times the rate of typical music-store downloads. Ultra-high-resolution 96kHz/24-bit downloads are planned as well.

“Musicians and sound engineers create incredible performances and amazing, lifelike recordings, only to have people download their work at 128 kbps from the popular music stores,” said HDtracks co-founder David Chesky. “This completely destroys the nuance of the recording and often introduces audible distortion. Our free “Ultimate Download Experience” album should prove to listeners once and for all that they can hear the difference between a CD-quality or high bit-rate file and a conventional download, even on an iPod®.”

About HDtracks
Founded by David and Norman Chesky of the respected audiophile-record label Chesky Records, HDtracks is a high-quality music download service offering a diverse catalog of independent music from around the world. HDtracks does not believe in DRM, and as a result, offers a selection of unencrypted files that play on any computer or portable device. HDtracks recognizes that while there are significant benefits to accessing music at the touch of a button in today’s computer age, preserving sound quality and the visceral experience of the live music performance should remain a priority. The HDtracks mission is to deliver the whole package: world-class music, unrivaled sound, files that play in any environment, and liner notes that enhance appreciation of the artist and album.

* Digital Rights Management encoding, or DRM, is a technology that limits the usage of digital media. HDTracks does not employ this technology, as the company believes that once its customers purchase music from its site, they have the right to play it wherever they wish on any device they choose.