As promised.
Adjusted the @sachu888 -supply to +-19.5 volt feeding the Pearl. No noise issues whatsoever 😍
It´s playing as I write this, Hans Theessink & Terry Evans "Visons". Opamp is LM-49720......... It stays !!!
Compared to my X-Ono clone it´s clearly a little more revealing in the highs. Lots of detail without being sharp.
Bottom end is impressive too. This is absolutely perfect.
Only issue left is a bit of hum (100 Hz). When connecting the ground wire from turntable it hums a bit or more
like snearing and nothing changes when touching tonearm.
Without the gound wire it´s dead silent, but a weak humming when touching the tonearm 🙁
Moving the PSU away makes no difference whatsoever.
Everything is wired according to build guide. Come to think of it..... I wired 2 extra LED´s for the front panel directly to
the power inputs before the 78/7915´s, but I have a hard time believing, that this could be the cause. Will fiddle around
with this issue tomorrow. I´m tired....... want beer and music now.
@wayne ............. hell of a little bugger you managed to put together here 👍👍👍
You could also solder a resistor between the loops of 2 of these https://www.adafruit.com/product/3825 and just plug them into the resistor holes when testing. When correct value was found you could then solder resistors into clean holes. The test points grip quite well in resistor size holes
Nice find 👍 👍
For those who might be interrested........ HUM IS GONE 😍
Had sanded all connecting sides of the enclosure before hand, so was a little worried..... obviously for no reason.
Tightened a couple of screws. rewired ONE connection from PSU to ground of the Pearl-3, and now dead silent
with arm/tt-ground connected.
This is (almost) better than good 😊😊😍👍
@Boydk: Great news. One of the first listening qualities I noted was the separation of vinyl surface noise and music. The vinyl noise is still there but the music is sufficiently separated so you can tune out the scratches and rumbling. Also, you will hear in the distance more of the original tape hiss from true analog recordings (typically pre-1983 ones). Ampex machines have their own hiss sound -- one that is very clear on some of the Ronstadt albums.
I find the transient response of the P3 better than my other pres (an E.A.R. 834 with sut and Slee's Accession MC). Overall, the P3 blows these two away and they are considered good phonostages in the audiophile world. Percussion can literally pin you to the seat when it is well recoded. Vocals are continuous with none of the dreaded digital harshness. The more I listen for timbre, the better the image becomes.
Enjoy and share your listening knowledge.
I find the transient response of the P3 better than my other pres (an E.A.R. 834 with sut and Slee's Accession MC). Overall, the P3 blows these two away and they are considered good phonostages in the audiophile world. Percussion can literally pin you to the seat when it is well recoded. Vocals are continuous with none of the dreaded digital harshness. The more I listen for timbre, the better the image becomes.
Enjoy and share your listening knowledge.
1. No... just moved one wire, Was from housing of the PSU to the housing of P-3.
2. No...... retired and getting lazy 🤣 .It worked, so no reason to try anything else 😊
I´m priviledged in some areas. My microridge/microlinear needle pick up very little noise, as it is.
Have been listening to this one for years now.
The most interresting part is, that the Pearl-3 lacks none of the qualities, I´ve learned to love from the X-Ono clone.
I would love to hear more, but "unfortunately" one of my friends is taking the Pearl-3 with him home to Bruxelles this afternoon.
If it performs as well in his place, as it does here (homebuilt monoblocks by me, Martin Logan Ascent, totally upgraded
Linn LP-12 with Lyra Delos & a Linn Kairn preamp), he´ll just buy it. So if I want to enjoy the Pearl-3 some more, I´ll just
have to put together another one 🤣🤣.
PS...... agree with all your listening impressions btw 👍
3-wire screened cable from PSU to Pearl. Earth on inlet via bridge rectifier and 10 ohm to PSU enclosure.
Had forgotten to connect the screen to riaa enclosure-ground. After that....... no more humming.
I finally put me P3 together and conducted all the checks with no real problems.
U1 bias appears to be high and want to make sure that I'm tracking the instructions and understand what I need to do next. I installed the 220 ohm resistor that came with the kit into R27. I'm getting a reading of 2.41V across R27, so I should replace the R27 220 ohm resistor with something larger. I have 470 ohm resistors that I plan to use these.
Is this correct and is there anything else I should do?
U1 bias appears to be high and want to make sure that I'm tracking the instructions and understand what I need to do next. I installed the 220 ohm resistor that came with the kit into R27. I'm getting a reading of 2.41V across R27, so I should replace the R27 220 ohm resistor with something larger. I have 470 ohm resistors that I plan to use these.
Is this correct and is there anything else I should do?
Do keep measuring the voltage over R27 when changing it. Replacing with higher resistance, the voltage tends to rise a
little bit as well. I ended up with 691 ohm, resulting in 4,1 mA.
And you´re right to raise R27. As of now you have 10,95mA, which is too high.
You´ll probably end up in my neighbourhood = somewhere between 680 & 820 ohm to get 2-4 mA 😉
little bit as well. I ended up with 691 ohm, resulting in 4,1 mA.
And you´re right to raise R27. As of now you have 10,95mA, which is too high.
You´ll probably end up in my neighbourhood = somewhere between 680 & 820 ohm to get 2-4 mA 😉
I think I'm good now. I replaced the 220R resistors with 681R resistors. I'm now getting 3V across R27 which is 4.4mA. Now to hook up the P3.
IT’S ALIVE!
It took me long enough, but I finally finished my P3. I’m a very happy camper now, enjoying it in the system.
My setup is a Thorns TP-125 MkII with TP-16 arm Shure M97eX Jico SAS stylus > P3 > ACP+ > F2J Clone > Blumenstein Orca speakers with subs
I normally have the FY22 Frontend as a preamp.
It took me long enough, but I finally finished my P3. I’m a very happy camper now, enjoying it in the system.
My setup is a Thorns TP-125 MkII with TP-16 arm Shure M97eX Jico SAS stylus > P3 > ACP+ > F2J Clone > Blumenstein Orca speakers with subs
I normally have the FY22 Frontend as a preamp.
There has been considerable discussion regarding alternate values for R27. I am led to believe that 220R is perhaps not the best choice to provide the preferred bias current through the opamp, given standard performance distribution of the J112 devices.
I intend to start with 499R at R27 and see where that leads. If the resulting current falls on the low end of the suggested range, I will be happy with that.
I intend to start with 499R at R27 and see where that leads. If the resulting current falls on the low end of the suggested range, I will be happy with that.