Musical Fidelity A1 Improvements

[juluska]

I made these improvements to my Musical Fidelity A1:

http://ignatiusprojects.blogspot.com/

¿do you now where to find the OPA4134 in dip14 format?
I removed the existing TL084CN and installed a dip14 socket to prove other opamps. Is there any other dip14 opamp to improve the sound of TL084CN.

Thanks

[Bonsai]

I didn't think it would b e possible to improve the A1.

[juluska]

Originally posted by Bonsai
I didn't think it would b e possible to improve the A1.

Probably true. But it's possible to dissipate heat better. Due to the heat produced the caps where suspiciously inflated and the pot was broken. The minimum changes to do are to remove the heatsink, install a better one with a fan and change the 10000uf cads and the Alps pot. See my photos:

http://ignatiusprojects.blogspot.com/

[Nrik]

I think the OPA4134 is out of production, so you need to find someone who has stock.

I am sure there are other alternatives. Search this forum for opamp threads, and lookup datasheet on the manufacturers websites.

[h_a]

Doesn't look like the OPA4134 is out of production, just that companies carry only the SOIC-package. Wanna go surface-mount ?

Have fun, Hannes

[juluska]

I have an OPA4134 in Soic package. is there any easy way to adapt it to DIP14 without soldering?

[Zen Mod]

@juluska

you're wasting time with some of these "improvements" .

go HERE and read what's problem with preamp stage itself .

you can do same as M. Hennessy , or you can look at this post in our local Serbian forum and make this line stage :

[jez]

Hi,

A word of advice.
Do not replace the TL074 used in the shunt regulated supplies to the phono stage with an OPA4134. It won't work. It's not just if it sounds good or not, it actually won't work at all.
It's ok to replace the other one in the line stage.

[senshu]

juluska-san,

I have had some opamps rolled on my MF A200, which is equipped with similar pre stage as MF A1.

TL074/084 ... Original. Warm, masked.
AD8620x2 ... Clearly audible improvement on resolution
OPA627x4 ... Significant improvement, still keeping MF's sound
TLE2074 ... Slight improvement on resolution
OPA4227 ... Dull. Maybe worse than TL074
TLE2144 ... Significant improvement, with colder sound tone

Last three newer 4ch opamps were my quite recent trials, and I found TLE2144 is quite impressive. Sound is full of details with somewhat cold sound tone, while OPA627 gave hotter sound.
LM49740 can be another option, though, I skipped it because I do not like the sound of LM49720 in my diy headphone amplifier.

You can find TLE2144 in Digikey at very reasonable price.
Good luck!

P.S.
Some pictures in my site;
http://d.hatena.ne.jp/web123/20090626

[destroyer X]

Say...audiophiles.... i am watching you with the A1, and i know how the A1 sounds... this way i feel myself interested to know the ones Japanese values.

I have worked for Sony, and i respect a lot your people, and the value of your opinion is strong in my mind.

Also, i would like to ask you the one is better between those chips i have here:

OPA2134
OPA1632
LM49860
LM4562
INA134
DRV134

Write to panzertoo@yahoo.com

Sayonara

Carlos