Plh

[mpmarino]

Where's the link to the pcb group buy?

[Vix]

Hi,


I was thinking about the knob…I like the idea of an amp having only two knobs, one marked as “Volume” and the other one as “Tone”. While we may have seen such a thing, now the “tone” control got a different character…

Just thinking….may it be that different positions of the knob will suit to a particular type of music? For example, I was experimenting with an Aleph current source on my ZEN V3. I installed a switch to disconnect the 1.5 K resistor, making it a CCS (switch off). I noticed that I preferred a constant current source while listening to easy music, or Jazz, while with Rock I preferred the Aleph current source (switch on). I even had an idea to connect a 1K ohm pot in series with 820 ohm resistor, so the range would be from 820-1820 Ohm, which should give me various percentage of AC gain….

By the way, I tried a 1.8 K resistor instead of 1.5 k. Did not like the sound. Returned to 1.5 K. Or none (switch off)...


Regards,

Vix

[rtirion]

Could there be a little mistake in the text under fig 8?

Figure 8 shows .... through R1 and R2. The source of Q1 follows
the Gate inout signal and drives Q3 in Common Source mode (v..

Should this not read:

Figure 8 shows .... through R1 and R2. The source of Q1 follows
the Gate input signal and drives Q2 in Common Source
mode (v..

And as a result

The Drain of Q1 delivers an inverted and amplified version of the
input signal to drive transistor Q2 in Common Drain mode (cur...

would read:

The Drain of Q1 delivers an inverted and amplified version of the
input signal to drive transistor Q3 in Common Drain mode
(cur...

Or am I missing something obvious?

Regards

[Nelson Pass]

Originally posted by Greg Erskine
I was just about to download the datasheet for the IRF244 and found it is now obsolete. I guess it may be still available for now.

It will work with just about any part. IRFP240's are a clean
replacement.

[Nelson Pass]

Originally posted by lumanauw
With this quality of "homework", you should be able to make commercial product from it (another FirstWatt maybe?), but you decided to put it as DIY project?

It might make a product, but I don't have to decide at this
moment, and it doesn't hurt me to put it out there in the
meantime.

[Nelson Pass]

Originally posted by Vix
On page 7 I read “ P1, R6 and C4 form a filter to take out power supply noise..." On the schematic (Fig. 8) it is C5?

Shall we dare to think what's gonna be next?

Right you are, and also the reference to P1 and R3 which should
be P3. Both are fixed, and Desmond is putting it up on

www.passdiy.com and it's also being sent to AudioXpress.

[Nelson Pass]

Originally posted by rtirion
Could there be a little mistake in the text under fig 8?
would read:

The Drain of Q1 delivers an inverted and amplified version of the
input signal to drive transistor Q3 in Common Drain mode
(cur...

Thanks. Missed that one too.

[Dennis Hui]

Originally posted by Nelson Pass

It will work with just about any part. IRFP240's are a clean
replacement.

Yippee! Sounds like I can use my IRFP044's...

Dennis

[lumanauw]

It might make a product, but I don't have to decide at this moment, and it doesn't hurt me to put it out there in the
meantime.

Right I forget to include a factor that a Nelson Pass have reached such an enlightment level, that his true customers will still buy authentic product, even the original schematic is floating around and they can built/buy the clone. The original gears have somekind of invincible thing that those who owns them is satisfied perfectly

[tlf9999]

Originally posted by lumanauw
his true customers will still buy authentic product, even the original schematic is floating around and they can built/buy the clone.

maybe Nelson has done studies on his customers but who is a typical Pass customer?

I doubt DIYers account for a meaningful portion of his customer base.