I have LEDs, but I turn them off while listening.
Listening postponed until tomorrow 😴
Jim made his test with naked boards too, so it should work, somehow: https://www.diyaudio.com/community/threads/pearl-3-burning-amp-2023.404054/post-7491775
Listening postponed until tomorrow 😴
Wow.
Wow, wow, wow 😍
This amp just sounds unbelievable gorgeous 😍
Diana Krall isn't in the other room, she is just here 😀
This amp has such an authority, powerfull bass, sweet highs... and the mids are to die for 😍
Many thanks to @wayne and all project participants!
(No noise, even without chassis. )
Wow, wow, wow 😍
This amp just sounds unbelievable gorgeous 😍
Diana Krall isn't in the other room, she is just here 😀
This amp has such an authority, powerfull bass, sweet highs... and the mids are to die for 😍
Many thanks to @wayne and all project participants!
(No noise, even without chassis. )
I've never heard such sound quality from a record. Period.
And I've been using record players for 42 years.
I'm a bit shocked.
And I've been using record players for 42 years.
I'm a bit shocked.
No noise without chassis is VERY impressive for a phono pre!
Not that your room isn't without potential emission, even more impressive
Congrats
Claude
Not that your room isn't without potential emission, even more impressive
Congrats
Claude
Congrats 👍
Yeah... It is an amazing little gadget, insn´t it?? 😍
Built one for a friend in Begium. His comment after 2 days: "Think I need to go through my entire record collection again !!
My red LEDs also blink once when I turn the amp on. I have one PSU per channel, so I think it has something to do with the PSUs behavior. Another thread mentions a power-on transient, and I think that could be it.
how have people damped down this transient? is it a constant with varying power supply approaches?
or is it a necessary "feature" in the good performance?
or is it a necessary "feature" in the good performance?
No, you were clear, just agreeing on the transient. Normally, one would turn P3 on first, then pre then power, making it no big deal.
Alternatively, if pre and power on, you would select mute, then turn on P3 also making it no big deal.
Like a big dummy ( omni dummy?) I flipped on P3 with BOTH pre and power in, AND had phono selected on pre....the resulting thump fried both channels in my XA 252! Like I said, totally preventable by proper switching order.
When I told this story, someone piped up about a known transient from P3 on turn on, and I accepted that as correct.....maybe mine (P3) has a problem? I sure didn't repeat the switch on problem!
Russellc
I think the dual mono PS is a good idea. I just have standard "mono" power supply. Really like the custom cases from Modushop, but it isn't large enough.
Guess I could have them make faceplate and rear panel in a larger version chassis, problem solved.
Better order another power supply so it's on hand.
Russellc
Guess I could have them make faceplate and rear panel in a larger version chassis, problem solved.
Better order another power supply so it's on hand.
Russellc
Just in case, I measured the voltage across R27=680 ohm, the result ist 2.93/2.98 volt which means 4.3 mA.
Done.
Done.
As others has noticed......
The "turn-on" "thump" is normal, and lasts shorter than a second.
If I switch the pre to "Phono" right after turning the P-3 on, I have a small DC-thump.
If I wait a second after switch on, no thump.
Also..... Both current LED´s blink once on startup, twice on turn-off.
All my builds were with different/various components. All behave the same way.
The "turn-on" "thump" is normal, and lasts shorter than a second.
If I switch the pre to "Phono" right after turning the P-3 on, I have a small DC-thump.
If I wait a second after switch on, no thump.
Also..... Both current LED´s blink once on startup, twice on turn-off.
All my builds were with different/various components. All behave the same way.
Thanks for the confirmation, @Boydk !
In the meantime I did a slight change in the feedback loop, I lowered R9 to 1.2 kohms in order to get lower gain, which means a total of 186 ohms when J2 is closed.
I just felt yesterday, that it was "too much", it was somewhat overdriven, but of course far from clipping.
Now it sings somewhat calmer, the "too much" has gone. I may check different R9 values between 1.2 and 2.2 kohms and set it to my liking.
Regarding hum... no, there is no hum, normally.
But one floor below me, a doctor has his large office, full of equipment. Yes, they're annoying... occasionally I get a humming noise, for a few seconds. So it's time for a chassis. Now I have to wait until 6 pm.
In the meantime I did a slight change in the feedback loop, I lowered R9 to 1.2 kohms in order to get lower gain, which means a total of 186 ohms when J2 is closed.
I just felt yesterday, that it was "too much", it was somewhat overdriven, but of course far from clipping.
Now it sings somewhat calmer, the "too much" has gone. I may check different R9 values between 1.2 and 2.2 kohms and set it to my liking.
Regarding hum... no, there is no hum, normally.
But one floor below me, a doctor has his large office, full of equipment. Yes, they're annoying... occasionally I get a humming noise, for a few seconds. So it's time for a chassis. Now I have to wait until 6 pm.
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Well, it could take longer today... this album was still sealed until today... sounds gorgeous, very impressive 😍
That confirms what Plott was saying. Like I said, the only "problem" I had was foolishly flipping it on with pre set to phono of all things
Russellc