ggetzoff,
Is everything well soldered (no cold joints)?
Also, maybe you could try «nichicon muse» electro caps at some point. they have high resitance and you may loose bass tightness a little, but tends to give a very nice tonal balance in general ( in my experience).
Yes, very carefully soldered. I obsess over solder joints. Yes, I could try that for both positions you are talking about.. Thanks for the suggestion.
just to be sure, regarding nichicons.... i'm talking about psu caps to replace your panasonic fc (i think this is what you have?)...
i meant decoupling on the amp board, and maybe also it could be beneficial upstream, back at the regulator as well....
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i meant decoupling on the amp board, and maybe also it could be beneficial upstream, back at the regulator as well....
Yes, it could. Speaking of which I made a very interesting discovery yesterday evening. I pulled the op-amp out and everything on the low end returned in my system, and the top end smoothed out. Mind you, my offset without the servo is right around 0 mv dc with very little drift.
So, that tells me, and exactly what Tea said: a single mono BiB is simply not enough to power this circuit properly. Yes, the opamp only needs a few ma to run, but I'm just saying....
Those people in this thread who've rolled their eyes at even the idea of different op-amps in the servo making a difference haven't heard my setup.
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found something interesting, a similar design...
Project 101 - High Power, High Fidelity Lateral MOSFET power amplifier
Project 101 - High Power, High Fidelity Lateral MOSFET power amplifier
Mind you, my offset without the servo is right around 0 mv dc with very little drift.
The DCG3 can be steady for bias drift and offset when well sinked and ventilated. But it may change with seasons and need re-trimming. The servo chip is an automated guardian for any drift scenario. Nearest to no chip was when with the AD823 in my subjective tests. I tried some op-amp types but I did not try everything out there of course. It prefers FET input chips in general due to the high impedance servo input filtering design.
Nonetheless, If there is an AC coupled input power amplifier following, the preamp's DC offset isn't an issue anymore. There you can go by using no chip unharmed.
found something interesting, a similar design...
Project 101 - High Power, High Fidelity Lateral MOSFET power amplifier
Short of... that loudspeakers amp is AC coupled discrete bipolar input & lateral Mosfet push pull output with capacitor separated AC/DC feedback path, when the DCG3 is DC coupled monolithic JFET input with cascoded SE CCS'ed vertical Mosfet output. Anyways, much later after I published it I learned here that there was an Erno Borberly headphones amp design with laterals once that was the closest in topology. DCG3 was developed from scratch though, I intentionally did not review other discrete mW output level amps so not to be affected. My goal was to make something with gain and potent output drive that won't be less than my DCB1 in resolution or musicality.
You can cease my personal computer and examine my 2015 design files evolution sir
I must have devised on breadboard and measured about a dozen ideas back then. Each one I listened to with cans and I copied it to Spice for archiving as I was tweaking it to another draft or abandoning it to different.
Here's one of those, one of the earliest. Has high rails, push pull BJTs, and outta loop SE Mosfet buffer. For your inspiration because you recently asked me what about such features I think
Why I had named some of those "FSL drafts" don't ask me, I forgot by now LOL
I must have devised on breadboard and measured about a dozen ideas back then. Each one I listened to with cans and I copied it to Spice for archiving as I was tweaking it to another draft or abandoning it to different.
Here's one of those, one of the earliest. Has high rails, push pull BJTs, and outta loop SE Mosfet buffer. For your inspiration because you recently asked me what about such features I think
Why I had named some of those "FSL drafts" don't ask me, I forgot by now LOL
Attachments
You can cease my personal computer
only if you cease my personnal sigma22
ok now...i'll be out of town for a few days...
i'll build as soon as i can
Vishay VS-HFA08TB60-M3 seems like a good diode for DCSTB?
https://www.vishay.com/docs/96190/vs-hfa08tb60-m3.pdf
P.S.: I have ON Semiconductor's MSRF860G in my BOM.
But I learned a new word "HexFred" a few days ago, so.. )
https://www.vishay.com/docs/96190/vs-hfa08tb60-m3.pdf
P.S.: I have ON Semiconductor's MSRF860G in my BOM.
But I learned a new word "HexFred" a few days ago, so.. )
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