1A6 to 1A7 is good for Iq
that across 0R27 is 430 to 460mV
What happens if the bias is kept very low, say 500mA or even 100mA?
500mA - low power then Big KlunK!
100mA - don't bother, buy second hand NAD or M. Levinson - cheaper way of hawing drek sound

100mA - don't bother, buy second hand NAD or M. Levinson - cheaper way of hawing drek sound

M. Levinson - drek sound
Hm. Is that M Levinson as in MLevinson or as in post M Levinson?
(Always thought he was considered one of »THEM«
buy second hand NAD or M. Levinson - cheaper way of hawing drek sound:
LMAO 😀
Hm. Is that M Levinson as in MLevinson or as in post M Levinson?
(Always thought he was considered one of »THEM«
amps
you know those amps, so filled with parts that no man alive can fix them
and why......
just joking of course, amp so heavy - must be good ......

Let it be sound. The Zen sound 🙂
And what a sound it is! THD spectrum attached at 1W and 8W at 8 ohms. Total THD at 1W is just 0.036%, and 0.035% of that is 2nd harmonic.
And what a silent amp! Nothing but the music. No hum/buzz at all with 96dB Klipsch loundspeakers! The most silent amp of all the FW clones I've build so far! Nothing, nada, zilch in Zen speak 😉
Thanks again for all who made it happen!
Papa is smart, outstanding and everything - Zen Mod is better, yet 🙂
-Alvis
And what a sound it is! THD spectrum attached at 1W and 8W at 8 ohms. Total THD at 1W is just 0.036%, and 0.035% of that is 2nd harmonic.
And what a silent amp! Nothing but the music. No hum/buzz at all with 96dB Klipsch loundspeakers! The most silent amp of all the FW clones I've build so far! Nothing, nada, zilch in Zen speak 😉
Thanks again for all who made it happen!
Papa is smart, outstanding and everything - Zen Mod is better, yet 🙂
-Alvis
Attachments
.....
Papa is smart, outstanding and everything - Zen Mod is better, yet 🙂
.....
I'm glad you like it 🙂
Papa's
Kung
is
funniest
Fu
for any of his Gizmos - be absolutely sure that he exactly knows and controls end result; you can take any of them (Gizmos) and try to improve - you'll get (in best case) something same good but different, but never better
what is better?
🙂
edit: how easy you did found setting procedure?
for any of his Gizmos - be absolutely sure that he [Papa] exactly knows and controls end result; you can take any of them (Gizmos) and try to improve - you'll get (in best case) something same good but different, but never better
edit: how easy you did found setting procedure?
Setting was easy (but I never found it being difficult with any other apm either). I started with trimpots set to the middle. It corresponded to about 1V5 bias current after initial warmup. So I just had gradually increase it to my desired 1V6. Same with offset. Nice and stable.
But it's something else what I liked most about your version, Zen Mod. I have a feeling that Papa makes his genius designs biased to his so well filled and matched stash of parts: lots of Toshibas, lots of mached MOSFETS etc. This makes life for us, simple Greedy Guys, interesting, but a bit more complicated. And you took Papa's idea and looked at it from a bit different perspective - no matchings, cheap and easily available parts (except Jfets, unfortuntely). Also nice thing about the PCB was included place for the GBR and convenient jumper for SE input. This is what I liked. Same good result, as you say, but with less hassle!
sissy common PSU
Hrrr.. I will definetely have to buy one of yours CRC PCBs with some of your kits 🙂 That also have a place for the thermistor! 🙂
With gratitude.
- Alvis
Let it be sound. The Zen sound 🙂
And what a sound it is! THD spectrum attached at 1W and 8W at 8 ohms. Total THD at 1W is just 0.036%, and 0.035% of that is 2nd harmonic.
And what a silent amp! Nothing but the music. No hum/buzz at all with 96dB Klipsch loundspeakers! The most silent amp of all the FW clones I've build so far! Nothing, nada, zilch in Zen speak 😉
Thanks again for all who made it happen!
Papa is smart, outstanding and everything - Zen Mod is better, yet 🙂
-Alvis



.....
But it's something else what I liked most about your version, Zen Mod. I have a feeling that Papa makes his genius designs biased to his so well filled and matched stash of parts: lots of Toshibas, lots of mached MOSFETS etc. This makes life for us, simple Greedy Guys, interesting, but a bit more complicated. And you took Papa's idea and looked at it from a bit different perspective - no matchings, cheap and easily available parts (except Jfets, unfortuntely). Also nice thing about the PCB was included place for the GBR and convenient jumper for SE input. This is what I liked. Same good result, as you say, but with less hassle!
......
yup - he made Aleph J for his production - as you said - all Toshibas of this world, Trainload of IRFP240 to choose from
so, this pcb and few choices resulting in overall simplification, are actually made to make life simpler to interested Greedy Boy **
same logic applies to Papa's pieces made exactly for Greedy Boyz - just look at all Diyaudio intended projects, not FW or PL products with expired production - he made everything possible to simplify things, while not cutting in intended level of performance
**edit: let's not forget that 6L6 asked for at least 2 LEDs; I forgot to include them ......... what is a power of restraint!

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Thanks for helping me through this Aleph-J build Zen!
I like to build amps with separate power supply for each channel, basically two mono in one box. Would 200VA/18-0-18V transformer be sufficient for one channel?
I like to build amps with separate power supply for each channel, basically two mono in one box. Would 200VA/18-0-18V transformer be sufficient for one channel?
What is the difference between IRFP150MPBF and IRFP150NPBF?I used IRFP150MPBF as advised in the BOM received from 6L6.
IRFP150NPBF Infineon / IR | Mouser
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