Upgrading amp internals

[tonapo]

I have enjoyed reading the various purify threads and this lead me to read the thread around different opamps. I currently have a Musical Fidelity M6si (https://www.musicalfidelity.com/products/m6series/m6si/) which I have had and enjoyed for a few years (connected to a Topping D90 via xlr into Kef Reference 1 speakers).

When I first had it I remember reading about the possibility of upgrading it which included the opamp. I didnt feel the need to upgrade the new amp at the time but I did end up emailing one of suggested UK firms to ask what was involved and I had a reply which I thought people here might be interested in. Here is the reply as to what would be changed if I did choose to go ahead.

“The upgrade involves replacing all electrolytic capacitors, opamps, power cable, speaker cable, speaker binding posts, my own special circuit modifications”

I also found a couple of pictures of a before and after, these were from another forum, so not my amp, so I can’t definitely say they are the result of the upgrade, but supposedly so, but I kept them as I thought I might want to refer to then in the future.

Anyway, I thought it might be interesting to get the views of people on here. So, any thoughts? What effect might this have on the amp etc and its performance?

 

[RayDunzl]

Do you have a problem with it that needs to be solved?

If not, why mess with it.

How does it measure now?

"If it ain't broke, don't fix it" has been my mantra since I learned at work to keep my hands off in-service Telephone Central Offices (before cell phones, when land-lines were all you got).

 

[Doodski]

“The upgrade involves replacing all electrolytic capacitors, opamps, power cable, speaker cable, speaker binding posts, my own special circuit modifications”

All MODs that may actually decrease integrity and won't change the sound quality. If you want better then get a better amp, get better speakers, use a EQ and calibrate it and don't waste time, effort and money performing useless MODs.

 

[UniPolar]

Electrolytics, power cable, binding posts -- Oh My ..

This would be better posted over at Audiokarma or DiyAudio rather than here on ASR..

Problem is, if you 'upgrade' and are not happy, you most likely have to live with those changes, as I would suspect they wouldn't offer any 'downgrade' or refund ... And your 'investment' would be diminished if/when you sell a 'modified' unit IMO - with no documented improvements....

Secondly, changes in the circuit may have the unintended consequence of causing premature failure of other components..

Don't do it..

 

[JeffS7444]

When I was younger and stupider (ha!) I used to perform those sorts of mods, and people seemed to like them. Today I wince at the thought, because without some sort of before-and-after measurements or at least a properly controlled ABX comparison, there's no way to gauge the effectiveness of the modifications.

There are other, more valid reasons to rework electronics, such as like replacing capacitor-malaise-era electrolytic capacitors or other likely problem areas, but I'm not aware of such issues with Musical Fidelity products.

 

[wwenze]

The only somewhat sensible mod would be to replace all the tier 3 electrolytic power capacitors because one of them spoilt. Or unreliable connectors.

This would be better posted over at Audiokarma or DiyAudio rather than here on ASR..

While it is fine and fun to post there, I think concurrently posting here is also good, because there are enough knowledgeable members here to point out when some wrong things worsen the performance or become dangerous. Diyaudio, the last time when I still visited there, was already 50/50 in terms of SNR. And many of the good members came to ASR anyway.

 

[Wes]

superglue some tubes on top

 

[Helicopter]

superglue some tubes on top

Seems like you could wire the heaters to mains via a voltage divider for that glow. I would probably go with the mesh plate 2a3s or some 845s since they look cool and should last a long time.

 

[dfuller]

Replacing the big electrolytics with better ones isn't a bad idea per se, and the neater AC wiring should help keep noise down a little, but otherwise I don't see any reason to make changes.

 

[MakeMineVinyl]

Your money would be much better spent one other parts of your system, especially your room's acoustics and your speakers. Your amplifier is designed to use the components which were specified in its original design. For instance, I see that the filter capacitors on the amplifier modules were made quite a bit larger (more capacitance). If the original rectifier which feeds those capacitors cannot handle the increased inrush current demanded by these larger capacitors, it could eventually fail, leading to a repair bill. Just replacing parts without intimate knowledge of the intent of the original design for 'better' ones is just not worth it, and most importantly, is very unlikely to make the amplifier perform better.

Unless there is a specific problem with the amplifier as-is, just spend your money on areas of your system which would benefit more.

 

[tonapo]

Thanks for the replies. And, just to be clear, I have not 'upgraded' the amp and nor was I looking too, as there were no clear benefits that I could see, perhaps if there was a fault then things would be different.

I think I was looking for two things by posting on ASR, one, affirmation that I had done the right thing by not doing anything, and two, (if point one is true) to highlight what is being sold to individuals as an 'upgrade' and perhaps give readers some pause based on the insights of members of ASR.

 

[Wes]

right, no clear benefits

it is rare when the correct answer to "upgrade?" is not "speakers, room, DSP, or masterings"

 

[Vini darko]

Bigger capacitance rail caps have some benifits and draw backs. Tidying wiring is fine. Replacing op-amps is very questionable.
Personally I would start with the volume pot. A stepped attenuator would be nice. Maybe relocate the transformer to the corner to make room for it.
However for a newish amp in this price bracket thats probably still under warranty I wouldn't touch a damm thing. Maybe in 10-15 years.