Hi,
Nicely done, enjoy!
Just a few notes, for whatever it is worth, just thinking out loud and not criticing of course...
1- It seems the caps are taller and don't allow the top lid fitting anymore. Regarding caps, the most important thing in this position and case is to go for very low ESR ones... is that what you did? Eventhough, bypassing them the way we did brought in OUR case further bebefits... you seem to have the skill to try it if not done already!
2- I hope you have secured your blue PS input terminal very securely, this is defo not the place you want anything to happen / getting lose...
3- The bigger PS can't harm of course, but let's be honest, this power amp doesn't really need it. The tiny traces on the board don't make allowance for much power in fact, so increasing V (and possibly A) doesn't make a lot of sense HERE. Of course, doubling the traces, or cutting them and using other routes (similar to what your did for your PS cable?), may make things different - perhaps that's what you did or intend to do? - say for short power burst, dynamic plays, as at the end the entire amp is not done for that eventhough the chip can cope with more if cooled appropriately.
BTW, what OPA did you go for?
Enjoy your music and thanks for sharing!
Claude
Nicely done, enjoy!
Just a few notes, for whatever it is worth, just thinking out loud and not criticing of course...
1- It seems the caps are taller and don't allow the top lid fitting anymore. Regarding caps, the most important thing in this position and case is to go for very low ESR ones... is that what you did? Eventhough, bypassing them the way we did brought in OUR case further bebefits... you seem to have the skill to try it if not done already!
2- I hope you have secured your blue PS input terminal very securely, this is defo not the place you want anything to happen / getting lose...
3- The bigger PS can't harm of course, but let's be honest, this power amp doesn't really need it. The tiny traces on the board don't make allowance for much power in fact, so increasing V (and possibly A) doesn't make a lot of sense HERE. Of course, doubling the traces, or cutting them and using other routes (similar to what your did for your PS cable?), may make things different - perhaps that's what you did or intend to do? - say for short power burst, dynamic plays, as at the end the entire amp is not done for that eventhough the chip can cope with more if cooled appropriately.
BTW, what OPA did you go for?
Enjoy your music and thanks for sharing!
Claude
I removed the dip socket and soldered the op1656 on the adapter.
Large capacitors 2200/50 Nippon Chemicon KY series, with low impedance and high ripple current. I haven’t done a bypass with ceramic capacitors (1uF 50V x7r) yet, since I like the sound quality in its current state. Following your advice, I bypassed the middle capacitor using 0.1 uF NPO.
My English is terrible, Google translator helps me communicate.
Hi, Claude!
Why does bypassing the central capacitor with C0G have such good efficiency? The circuit already contains a small capacitor that bypasses it. Apparently it is “bad” - Z5U, Y5V?
Attachments
Ahhhhh.... Why indeed?
Let's face it, given the posters here, there were many different boards and also some variations on this amp despite carrying the same name, even changing the gain of the preamp section.
The first questions we may ask are:
In the latter case, let's face it, this unit cost very little money. Hmm, so little money that you have to wonder what parts were used, if at all. If you put the required build of material together, even allowing a large discount as manufacturer, all parts and casing and assembly, plus some margin... it doesn't really add up. Bottom lines, some expected parts are either not there, or are fakes / very low quality ones, it just can't be.
I am glad you are enjoying this mod on the 5th middle cap, which as posted (and as you know) has a different function than its neighbours. All our game was to buy the cheap amp as it was (you can't get all this any cheaper by yourself) and replace or bypass parts at what we felt strategic places. Some times it worked better than expected, sometimes not. That's why we posted iall what we did to avoid following people all the hassle. It has to be clear that if the amp would have had proper PS & Co with quality parts from the start all this wouldn't exist!
It is also clear, as we posted during our comparison with commercial amps, that for 200E and some work you could end up with something sounding as a commercial 1500E amp. It won't be a giant killer and get higher though, regardless what you di, you hit a limit then, starting in the bass and soundstage vs high end products. The interesting thing is that sometimes replacing with quality parts brought benefits, but even that these sometimes benefited from a bypass! The other thing, VFM, is that not replacing the supposedly lower quality parts and just bypassing them with high quality parts, sometimes various, worked out to be easier, cheaper and sounding the same or better.
The good thing is we tried it all, and have now a clear view on what is worth doing and in what way - all only in our humble opinion of course - and we posted benefits with narrative/ description on how to do it and what sonic plus to expect and even used a point system to give an amplitude on the improvements. So everybody can decide how far to go, or if the mods are really audible for him or not. We went all the way / max moddifications on our 2 first units because we wanted to test all possibilities and always have an amp baseline for comparison, hence 2 units... but on the third unit I built for my mother we just went for the lightweight mods we felt were best VFM. As in a post summing it all, it was 90% of the sound for 20% of the cost and hassle...
At the end, some mods simply work better than others, and as in every build the PS, whatever one you consider (amp, preamp section, RIAA...), is key...
Enjoy tweaking and let us know if you share our findings
Claude
Let's face it, given the posters here, there were many different boards and also some variations on this amp despite carrying the same name, even changing the gain of the preamp section.
The first questions we may ask are:
- does the bypass cap exist on all units?
- if so, what is used?
In the latter case, let's face it, this unit cost very little money. Hmm, so little money that you have to wonder what parts were used, if at all. If you put the required build of material together, even allowing a large discount as manufacturer, all parts and casing and assembly, plus some margin... it doesn't really add up. Bottom lines, some expected parts are either not there, or are fakes / very low quality ones, it just can't be.
I am glad you are enjoying this mod on the 5th middle cap, which as posted (and as you know) has a different function than its neighbours. All our game was to buy the cheap amp as it was (you can't get all this any cheaper by yourself) and replace or bypass parts at what we felt strategic places. Some times it worked better than expected, sometimes not. That's why we posted iall what we did to avoid following people all the hassle. It has to be clear that if the amp would have had proper PS & Co with quality parts from the start all this wouldn't exist!
It is also clear, as we posted during our comparison with commercial amps, that for 200E and some work you could end up with something sounding as a commercial 1500E amp. It won't be a giant killer and get higher though, regardless what you di, you hit a limit then, starting in the bass and soundstage vs high end products. The interesting thing is that sometimes replacing with quality parts brought benefits, but even that these sometimes benefited from a bypass! The other thing, VFM, is that not replacing the supposedly lower quality parts and just bypassing them with high quality parts, sometimes various, worked out to be easier, cheaper and sounding the same or better.
The good thing is we tried it all, and have now a clear view on what is worth doing and in what way - all only in our humble opinion of course - and we posted benefits with narrative/ description on how to do it and what sonic plus to expect and even used a point system to give an amplitude on the improvements. So everybody can decide how far to go, or if the mods are really audible for him or not. We went all the way / max moddifications on our 2 first units because we wanted to test all possibilities and always have an amp baseline for comparison, hence 2 units... but on the third unit I built for my mother we just went for the lightweight mods we felt were best VFM. As in a post summing it all, it was 90% of the sound for 20% of the cost and hassle...
At the end, some mods simply work better than others, and as in every build the PS, whatever one you consider (amp, preamp section, RIAA...), is key...
Enjoy tweaking and let us know if you share our findings
Claude
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