Pearl
Hi, I was going to build a tube phonostage and then read some positive comments on the Pearl 2 and decided to try it 🙂 So I have just ordered the pearl 2 pcbs and fets from passdiy and am slowly reading through this thread. Are there any major changes to the BOM in the passdiy article that I need to be aware of, before ordering components?
(Once burned as I didnt remember the zener change recommended in the F6 thread when ordering parts for F6 🙁 som Im currently waiting impatiently for 4x zeners and 4x resistors being FedExed priority from Mouser in TX to Norway, will still take a week at least If they dont stop for a week or two in Norwegian customs).
Hi, I was going to build a tube phonostage and then read some positive comments on the Pearl 2 and decided to try it 🙂 So I have just ordered the pearl 2 pcbs and fets from passdiy and am slowly reading through this thread. Are there any major changes to the BOM in the passdiy article that I need to be aware of, before ordering components?
(Once burned as I didnt remember the zener change recommended in the F6 thread when ordering parts for F6 🙁 som Im currently waiting impatiently for 4x zeners and 4x resistors being FedExed priority from Mouser in TX to Norway, will still take a week at least If they dont stop for a week or two in Norwegian customs).
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No changes, it’s a mature design. If you have any questions about part substitutions please ask here in the thread.
Order extra ZVP3310 mosfets, about 1/2 the builders blow one during assembly as they are incredibly static sensitive. Having an extra or 3 on had at the beginning is much cheaper than ordering a replacement later.
Order extra ZVP3310 mosfets, about 1/2 the builders blow one during assembly as they are incredibly static sensitive. Having an extra or 3 on had at the beginning is much cheaper than ordering a replacement later.
Thanks Jonny Canuck, there is no lack of stuff to read on the pass pages, very active forum.
Over on the M2x thread there's discussion of mother-daughter boards. Any interest in this type of arrangement for the Pearl ? If I were to do it I would separate the input and output stages, place the power regulators on another board, and allow for SMD input JFETs.
Why, one could even have an output stage with enough headroom to accommodate moving magnet cartridges!
Why, one could even have an output stage with enough headroom to accommodate moving magnet cartridges!
combinations
Anybody try to combine Pass DIY projects. Ba3 pre with Pearl 2 or even a Ba3 Pearl 2 and the new headphone amp all in same box sharing a power supply (in separate box of course). I'm thinking of trying to build a Pass Ba3 based "integrated." Discussion of stacking mother boards got me thinking of how I could fit all this into one box. I'm a little worried about noise introduction into the Pearl.
Anybody try to combine Pass DIY projects. Ba3 pre with Pearl 2 or even a Ba3 Pearl 2 and the new headphone amp all in same box sharing a power supply (in separate box of course). I'm thinking of trying to build a Pass Ba3 based "integrated." Discussion of stacking mother boards got me thinking of how I could fit all this into one box. I'm a little worried about noise introduction into the Pearl.
It could be done, and work great!
If the transformer is in a different box and you'll not worry about noise.
If the transformer is in a different box and you'll not worry about noise.
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I read somewhere that there was a gerber file for the Pearl II audio circuit board. Can someone post a link if that exists? I looked on the Pass DIY site and could not find one.
I don't think there is. Perhaps, but I haven't ever seen it.
A PCB set and the unobtanium matched Toshiba Jfets are available at PassDIY.
A PCB set and the unobtanium matched Toshiba Jfets are available at PassDIY.
You may be correct. The person that said there was a gerber file for the Pearl2 may have been thinking about the line amp circuit board on the Pass DIY site. There is a gerber file for that board on the site. Oh well. I will just buy the boards.
In the passdiy store they mention that you can download the gerber files to build your own PCB boards. Clearly the files are wrong as they are for the B1.
I contacted passlabs as their email is stated on the site and got the files via email. They had the intention to fix the files on the web page. That was sometimes last year.
Before you ask, I’ll not share the files without permission.
I contacted passlabs as their email is stated on the site and got the files via email. They had the intention to fix the files on the web page. That was sometimes last year.
Before you ask, I’ll not share the files without permission.
Hey guys
The power supply for my PEARL 2 requires 22 v secondaries. I have a 100VA AVEL transformer with 25v secondaries. All the caps are 35 volt Nichicons. Does anyone see a problem with using this transformer. The original transformer I was going to use had the required 22v secondaries but is too tall to fit in the chassis.
Thanks
The power supply for my PEARL 2 requires 22 v secondaries. I have a 100VA AVEL transformer with 25v secondaries. All the caps are 35 volt Nichicons. Does anyone see a problem with using this transformer. The original transformer I was going to use had the required 22v secondaries but is too tall to fit in the chassis.
Thanks
25V AC rectifies to 35VDC minus a volt or two for the diode drop. (AC V * 1.4 = DC V)
Under no load it will be more than 35v. Under load it's going to be 33ish. That's a bit tight for 35v caps.
What are you using for the raw DC supply? Can you run a few resistors in series with the caps and CRCRC? I knocked down a few volts doing that... Or just get bigger voltage capacitors.
Make sure the regulators you have can take the input voltage you give it.
Long story short, you can use it with a bit of thought. Use what ya got. 🙂
Under no load it will be more than 35v. Under load it's going to be 33ish. That's a bit tight for 35v caps.
What are you using for the raw DC supply? Can you run a few resistors in series with the caps and CRCRC? I knocked down a few volts doing that... Or just get bigger voltage capacitors.
Make sure the regulators you have can take the input voltage you give it.
Long story short, you can use it with a bit of thought. Use what ya got. 🙂
Thanks 6l6
I think it would be easier(for me) just to get another transformer. I can get a new 160va Avel with 22vac secondaries less than $50. I am using twin SKA audio GBS50 power supplies. One to rectify and the other for additional smoothing. Total of 24 4700uf caps-12 per rail.
Tm
I think it would be easier(for me) just to get another transformer. I can get a new 160va Avel with 22vac secondaries less than $50. I am using twin SKA audio GBS50 power supplies. One to rectify and the other for additional smoothing. Total of 24 4700uf caps-12 per rail.
Tm