And yes, I have a Massive Attack album that is divided into 3 LPs
If it's Mezzanine, then you are one lucky
If it's Mezzanine, then you are one lucky
It's not Mezzanine, it's the 100TH WINDOW, but it's not bad either
But 3 x 180gr, it's kindda heavy
Brds,
nAr
So can I use this power supply board. Its used for a chip amp, article says with a 22v tran will get 34v rectified output. THere is an article that gives more info on the power supply on the website.
DIY Chip Amplifier Kits, PCB's, Components and Information.
DIY Chip Amplifier Kits, PCB's, Components and Information.
Question
On the .pdf, it states that R26=499/1V/2mA which is mostly a typo (on the schematic, it is R28 that is 499R). Assuming the value read on R28 is 1V, it says 2 mA current for the diff pair Q4 & Q5, which leaves each half to 1 mA or so ...
On the opposite side, the Q6 to Q9 run with a 10R source load, which seems a pretty high current compared to the diff. pair of the next stage.
Which leads me to that question : before getting the 370s or 170s, which grade to choose? GR seems fine for the diff pair, matching VGS mostly, but for the input JFETS I would pick some BL grade before matching them by IDSS range ... am I correct ? How to calculate the amount of current in each JFET Q6 to Q9 ?
Best regards,
nAr
On the .pdf, it states that R26=499/1V/2mA which is mostly a typo (on the schematic, it is R28 that is 499R). Assuming the value read on R28 is 1V, it says 2 mA current for the diff pair Q4 & Q5, which leaves each half to 1 mA or so ...
On the opposite side, the Q6 to Q9 run with a 10R source load, which seems a pretty high current compared to the diff. pair of the next stage.
Which leads me to that question : before getting the 370s or 170s, which grade to choose? GR seems fine for the diff pair, matching VGS mostly, but for the input JFETS I would pick some BL grade before matching them by IDSS range ... am I correct ? How to calculate the amount of current in each JFET Q6 to Q9 ?
Best regards,
nAr
When I layed out the Pearl Two allowance was made for a lag capacitor around the ZVP3310. After building more of them I find it is not needed. I suggest you just leave it out. Your mileage may vary if you roll your own boards or change parts. Saves finding a good 10 PF cap.
When I layed out the Pearl Two allowance was made for a lag capacitor around the ZVP3310. After building more of them I find it is not needed. I suggest you just leave it out. Your mileage may vary if you roll your own boards or change parts. Saves finding a good 10 PF cap.
Question: if I use same layout and ground planes but ZVP3306A instead of ZVP3310, will the 10 pF capacitor needed or can I remove it as well
I have no oscilloscope here to check the square wave
Brds,
nAr
If you don't have a scope the best thing to do is check the gain at 1K.
51-55 dB is the range. if it oscillates this will usually show wrong.
An inverse Riaa and sweeping works well also. You want that nice HF roll off.
Save $ for a scope they have gotten inexpensive and are invaluable.
51-55 dB is the range. if it oscillates this will usually show wrong.
An inverse Riaa and sweeping works well also. You want that nice HF roll off.
Save $ for a scope they have gotten inexpensive and are invaluable.
The boards will be arriving after we return from CES in Las Vegas.
They are sized like the Pearl and will drop in. We will sell with matched fets.
A power supply board will follow if anybody wants one. ???
Is this still in the pipeline? I know its a simple power supply and all, just wondering.
Russellc
Is this still in the pipeline? I know its a simple power supply and all, just wondering.
Russellc
The power supply schematic is included in the .pdf
It is simple enough to allow fast, reliable and neat P2P wiring into the dedicated PSU box, in my opinion.
For that project I will use Vishay 1% resistors, Vishay MKP 1% caps for the RIAA correction and bypass output capacitor, Muse for the output ones (22uF/25v); Elna 3300uF/35V and for the 10000uF/40V, the new Mundorf M-Lytics AG séries
Input and output RCA connectors will be Silver Bullet ones
Best,
nAr
Question: if I use same layout and ground planes but ZVP3306A instead of ZVP3310
Any equivalent P-Channel version of that. Can anybody suggest N-Channel JFet with Gfs above 22mS?
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