She is EE Diploma.
She has no experience in Hi-Fi Amplifier but designed Super Het Radio and Tape Decks for Small companies here in India back in 70s.
Her first design was a Tape Boom Box in 1971 (I think she was 21yrs and 2 yrs married already). All gain stages uses Panasonic 2SC series , Some form of discrete DNR , BEL India AC188 and AC187 in Push Pull Class B stage for speakers.
She is a member of noisy Germanium transistor cult.
Now a days she doesn't solder anything ( She can't see properly , She is in her 70s) but help me to tidy up stuff and Etch PCB while i am proto typing.
She sounds amazing.
Thanks to Pete for the valuable insight into his build. He has been a gentleman in providing me with a pair of boards and ceramic pads for the chips....transatlantic obviously. This forum has some incredible members.
My build will be slow but I will update here as and when!
Thanks to Pete for the valuable insight into his build. He has been a gentleman in providing me with a pair of boards and ceramic pads for the chips....transatlantic obviously. This forum has some incredible members.
My build will be slow but I will update here as and when!
Thanks Claude...if you saw the PS board I used it’s got so many Mundorf film cap filters on it I don’t think any X7R/C0G bypasses would bring out any better sounds. I know you wanted me to try...
This was a fun little project. Rummaging through stuff I found a pair of amp boards I got from someone (maybe from X?) ....DLH Amplifier: the trilogy withPLH and JLH amps. I guess it’s a Class A amp. I have to do some reading up on its build now.
Pete
Francois: When I saw this wonderful little project I understood the designers wanted to provide an inexpensive, stable & pleasing-sounding build (as any capable designers would). I just looked at the easy signal path tweaks that would change the sound (for better I hoped, maybe worse or no different) and give folk some options.
I looked immediately at R4, R1, R3, R15, & C28. R20, R2 & C18 were also in consideration. But, I had to built it stock first. It was a nice amp just as is and I hoped my tweaks would allow some positive variations.
I think putting the Dale’s at R1, R3, R4 and R15 were the biggest sound changers. I’ve used them before in another LM3886 build. C18 & C28 changes was just pure snobbiness on my part, came from previous amp builds and were guesses.
The matching of R11 & R14 was an uneducated change on my part. When I measured the incoming voltages (+ & - ) to the opamp they weren’t the same. Since the regulators’ outputs are set by the 2 resistor pairs across pins 1&2 that whole exercise may have been electronically meaningless, because I think I should have matched R12&R13 as well, looking at it now.
Time to measure voltages again...
Pete
My pair was built to the BOM with the 4.7 caps at C1 and the WIMA caps at C27. They sound great. Listened to them for three nights at 2-3 hours a night. I use the speakers X posted here as a homage to the LS3. I used a few different sources and I was very happy with the sound of the amp. Most days I listen to an F6 with Korg Nutube pre. so don't think you need a lot of upgraded parts to get this amp working very well.
Nor do I want to discourage you from trying stuff. My C1 caps are physically huge and ordered because the ones on the BOM were on back order. Maybe they make a difference maybe not but the bass is good and the music was pulling me in. To me that's good enough.
Nor do I want to discourage you from trying stuff. My C1 caps are physically huge and ordered because the ones on the BOM were on back order. Maybe they make a difference maybe not but the bass is good and the music was pulling me in. To me that's good enough.
Thanks for the information. Solder I use is a 63/37 and 0.6mm. I will try a smaller size of solder and possibly pick up a needle type solder tip. I have one already, but I think I over heated it as it has a blue tinge on the body, and not sure that it will hold solder anymore
Waiting on some boards and have to order a few new parts.
Waiting on some boards and have to order a few new parts.
As I never was disappointed with Reichelt, my intention surely isn't bashing. Anyway, we have to consider that Reichelt isn't a first hand distrobutor, but a reseller. Especially when it comes to delicate things like these, one has to be aware of that.
Best regards!
I concur about using the Elnas at C5&11. They take a bit to settle in but they do pleasantly change the sonics. Smoother, possibly a bit airier but that’s subjective. Bass response isn’t affected as far as I can hear. I don’t really crank up the music so I can’t confirm what happens to the overall response & attack with only 320uF per side when the system is pushed. It’s too bad all the big cap PCB positions weren’t made with slightly bigger mounting diameters.
Dibya....did you ever try replacing C6&9 with Silmics as well? Ever try caps other than FCs to drive the signal or is ESR important here?
Regards, Pete
