Aiming for 1volt as in the build guide. Is it safe to increase bias?
Now my BA3 is up to 1V bias. Output 2V from 1V sine wave. I use original schematic except for P1 and P2, they are 1k. Shouldn’t output be 3V? Without tinkering with P3 I have THD% 0,4. It sounds detailed and controlled but there is some something missing. I can only describe it as ”it’s not B1K”. Do I miss some 2H? Du anyone have suggestions how to tweak BA3 to a friendly tone?
How much 2H is reasonable? The big >3H, are the only in my not so sophisticated oscilloscope?
Volume pot before or after is next on the test list.
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show me schm your'e using and write what differences in parts are exactly
edit: in fact , there is no need
increase gain simply increasing value of final I/V resistor
you can't change THD Spectra without trying with P3 , and you must do that , to find setting you prefer sonically
if B1 is positive reference to you, you need to find setting with 2nd harmonic dominant and lesser THD overall
edit: in fact , there is no need
increase gain simply increasing value of final I/V resistor
you can't change THD Spectra without trying with P3 , and you must do that , to find setting you prefer sonically
if B1 is positive reference to you, you need to find setting with 2nd harmonic dominant and lesser THD overall
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Gents! I wonder if this a suitable PSU for this pre.
https://www.google.com/url?sa=t&sou...Vaw1BQt8xUZ5NByPAEWKp6PRt&cshid=1587221127472
Thanks in advance ��
https://www.google.com/url?sa=t&sou...Vaw1BQt8xUZ5NByPAEWKp6PRt&cshid=1587221127472
Thanks in advance ��
I have used this PSU to wonderful effect -
Dual/Bipolar LV-Reg
And I like this transformer, it's much more current than needed, but it's the smallest they make that is shielded.
AS-0518 - 50VA 18V Transformer - AnTek Products Corp
Dual/Bipolar LV-Reg
And I like this transformer, it's much more current than needed, but it's the smallest they make that is shielded.
AS-0518 - 50VA 18V Transformer - AnTek Products Corp
I have used this PSU to wonderful effect -
Dual/Bipolar LV-Reg
And I like this transformer, it's much more current than needed, but it's the smallest they make that is shielded.
AS-0518 - 50VA 18V Transformer - AnTek Products Corp
Do 18v secondaries get you the regulated 24v, or do you need more to make the regs run properly? I may be thinking about the 7824/7924 used in Pearl.
Oh, good point!! This is the BA-3 thread, not the BA2018... need 24V rails...
Use this transformer -
AS-0520 - 50VA 20V Transformer - AnTek Products Corp
need 24V rails...Use this transformer -
AS-0520 - 50VA 20V Transformer - AnTek Products Corp
Oh, good point!! This is the BA-3 thread, not the BA2018...
Use this transformer -
AS-0520 - 50VA 20V Transformer - AnTek Products Corp
Doesn't he need 28-30V to regulate down to 24?
20VAC will rectify into 28VDC, minus 1.4 from the diodes, giving 26.6VDC. This leaves more than a volt and a half for the regulators (which they need) and would work fine and nothing gets hot because there's not a bunch of voltage to throw away.
And anymore everybody's line voltage is higher than normal, which will give a little extra voltage off the transformer.
The AS-0524 would work nicely as well.
And anymore everybody's line voltage is higher than normal, which will give a little extra voltage off the transformer.
The AS-0524 would work nicely as well.
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