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Old 11th August 2019, 08:22 PM   #251
ClaudeG is offline ClaudeG
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Hi Plasnu,

Perhaps my post wasn't clear? Trying again...

I don't want to start a debate and I am defo not commenting if the OP is pleased or not with his device or his sound... how could I?

I am solely commenting on:
"There is no sonic advantage of H2 addition. Up to some level it remains inaudible, then it starts to mess the transparency". That doesn't match my tests playing solely with H2 levels.

I can say that for me playing with the (H2) trim pots does indeed make quite a sonic difference. Better or worst is subjective, but a difference 'yes'. I doubt that the trim pot position has an effect on microphonics variations that you suggest I could like :-)

Are there microphonics? Perhaps... Do I like the sound? Yes! But that wasn't the point. The point is playing with H2 solely does impact the sound and for me at a certain H2 level and with negative phase it does sound better than no H2 or other lower or higher H2 levels, so my case differs from what the OP stated. That's all what I wanted to say.

That is in my system quite audible with very simple LS and no filter at all (my HP!!!) and also with my LS which are... 4 ways Infinitys that have, err, quite a complex filter (sadly).

I am with you that H2 signature of power amp... and IMHO also source does matter a lot. For me there is quite a sweet spot and I don't want to overdo it re 'total H2 level of the entire reproduction system'. In short, if your source, or as suggested your power amp, does produce already the right level of H2 you like adding the B1 Korg won't be a good idea. As of me, I liked best half the suggested level, which sounds like a lot less but is in fact still quite a lot of H2... but that's just me.

All IMHO, don't want a debate, just saying that playing with H2 was a revelation for me and for sure more research work should take place. And yes, distorsion signature and levels for sure don't say much about the sound: eventhough they would look similar sound can differ quite a bit as numerous mags with lab tests have revealed over the decades.

I hope I made my previous post clearer on H2 impact, while still outlining experiences may differ for each individuals and / or perception levels and I respect that very much of course

Claude

Last edited by ClaudeG; 11th August 2019 at 08:27 PM.
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Old 11th August 2019, 09:45 PM   #252
Nelson Pass is offline Nelson Pass  United States
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H2
Ground is the reference. You can put the probe right on the
Jfet leads.
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Old 11th August 2019, 10:46 PM   #253
plasnu is offline plasnu  United States
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Quote:
Originally Posted by ClaudeG View Post
I hope I made my previous post clearer on H2 impact, while still outlining experiences may differ for each individuals and / or perception levels and I respect that very much of course
I apologize I made you feel that your previous post was unclear. I fully agree with you. Everyone should have a different opinion about H2 experiment.

Since this is an experiment, I personally want to hear more negative comments about H2 in this open discussion. Saying something negative about H2 is not easy in this atmosphere , and I just wanted to support PMA's opinion mainly because of this reason. I did not intend to start debate with you.

I'm a believer of single ended amps. I have been experimenting H2 because I really want to know why single ended amps sound good to my ears. I would say my experiment is still unsuccessful. I still have a mixed feeling (finger-crossed) about pre-generated H2 distortion based on my experiment so far.
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Old 12th August 2019, 02:13 PM   #254
ClaudeG is offline ClaudeG
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All clear Plasnu :-)

Negatives... or kind of, yep, here we go:

1) I have set up a certain H2 level on my B1 Korg, but I do realise that this "optimal level" may vary if using HP or LS. Further, if changing a component all this will needed to be done again probably. As said I "feel" (but can't prove, more research work is required here) that for me there is a given optimal H2 level for the entire (HIFI) system, from source to amp... or perhaps even to LS if they do produce H2 (??). So each component change means tweaking again, and my ideal setting might not be yours if systems differ, eventhough we would like the same H2 profile / level. Just a felling. Positive is I see all this as a nice plus and now I do know how the sound varies with he trim pot so adjustment should be easier / quicker.

2) Well, I have to confess all this negative phase and H2 level outlines how much we do hear / process with our brain vs just our ears (hello psychoacoustic), and somewhere a negative could be that I don't like to be tricked so easily LOL! But then Papa did it so nicely and I discovered something about me and... I like it better that way, with negative phase. Ahhhh! :-)

Have fun experimenting and thanks again for sharing your findings

Claude
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Old 12th August 2019, 06:44 PM   #255
Big Guy is offline Big Guy  United States
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Quote:
Originally Posted by Nelson Pass View Post
Ground is the reference. You can put the probe right on the
Jfet leads.

Using "2ND HARMONIC GENERATOR" as reference and taking readings LEFT to RIGHT, I measure 5.485 V; 5.54 V; 19.7 V respectively.


Did I get the "right" answers?
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Old 12th August 2019, 07:45 PM   #256
Nelson Pass is offline Nelson Pass  United States
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H2
Attached is the art from the pcb. I have labeled 3 points where you
should measure approximately 5, 5, and 15 volts respectively.
Attached Images
File Type: jpg H2 PCB VOLT.jpg (313.0 KB, 252 views)
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Old 12th August 2019, 07:49 PM   #257
Nelson Pass is offline Nelson Pass  United States
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H2
By the way, have you tried removing the LED readout?
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Old 13th August 2019, 07:19 PM   #258
Big Guy is offline Big Guy  United States
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Quote:
Originally Posted by Nelson Pass View Post
Attached is the art from the pcb. I have labeled 3 points where you
should measure approximately 5, 5, and 15 volts respectively.

From the left, measured 5.44V 5.48V 15.65V (same as noted on pcb)


Quote:
Originally Posted by Nelson Pass View Post
By the way, have you tried removing the LED readout?

At your prompt I did remove the LED meter and whine went away which is great.


Having said that, my intent was to have the meter be a built-in indicator of both power ON and a reading of the (adjustable) output voltage so would have a way to reset to original value without messing with meter. Is there a way to wire into the circuit to fulfill my goal without creating the whine?



I think I wired it properly with RED/WHITE to center pin of regulator and BLACK to ground. Hopefully this is correct?!


Mini DC 0-30V BLUE LED 3-Digital Display Voltmeter

Guaranteed QUALITY! We DO NOT sell inferior goods! This high-accuracy meter displays number from 0.01 t0 30.0V.
Some cheaper meter only reads from 0.1 to 30.
If you have any questions, please feel free to ask and contact us to resolve the issue before opening a case.
Thanks a lot!
The display color is bright blue, It is much beautiful in reality than in picture!
Click the image to open in full size.


Specifications:
  • 100% brand new and high quality.
  • Measuring range: DC 0V--30V
  • Input range: DC 2.7V-30V
  • Max Input: DC 30V. The device can be damaged if input is over 30V
  • Display Color: BLUE
  • Display: Three 0.36 "digital tube
  • Measurement accuracy: 0.1%
  • Refresh rate: about 300mS / times
  • Input impedance: About 100K
  • Dimensions:33mm*15mm*10mm
  • pitch of holes:28mm
  • aperture size :2.8mm
  • Operation Temp: -10℃-+65℃
If you have any questions, please feel free to ask and contact us to resolve the issue before opening a case.
Thanks a lot!
Wiring:
  • Red wire: Power supply +
  • Black wire:Power supply -, Measured -
  • White wire: Measured +
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Old 14th August 2019, 06:06 PM   #259
Nelson Pass is offline Nelson Pass  United States
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H2
The meter is a digital instrument with digital noise, and is drawing power from
your supply. Probably you want a voltmeter with a separate power supply,
or maybe a passive meter.
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Old 16th August 2019, 04:05 PM   #260
Big Guy is offline Big Guy  United States
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Quote:
Originally Posted by Nelson Pass View Post
The meter is a digital instrument with digital noise, and is drawing power from
your supply. Probably you want a voltmeter with a separate power supply,
or maybe a passive meter.

In light of resolving whine issue by removing the LED meter from the H2 circuit, tried a couple of things...


(1) Powering the meter with the wall wart rather than the Vout of the regulator = NO NOISE
(2) Powering the meter with a 9V battery = NO NOISE
Will include an ON/OFF switch while I am at it.


On to listening
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