Hermida Mosferatu  [traced]

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Tom1884
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Post by Tom1884 »

I can't find schematics or internal pics of the actual commercial Hermida Mosferatu.
Could someone post links, pics or .sch? Thanks!

roseblood11
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Post by roseblood11 »

I just found this:

https://i49.photobucket.com/albums/f252/ ... feratu.gif

No idea, if it is correct...

roseblood11
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Post by roseblood11 »

...but for my ears a Zendrive with a larger gain pot (1M instead of 500k) sounds more interesting

Tom1884
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Post by Tom1884 »

They say that this schematic is an old version, much distant from the actual commercial version... :(

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reneshelle
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Post by reneshelle »

Interesting schem. dual gain stages and soft clipping for half the waveform and hard clipping for the other half. Could be fun to tweak around with.

But I try to remember the fact that I don't need more drive pedals

freq67
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Post by freq67 »

roseblood11 wrote:I just found this:

https://i49.photobucket.com/albums/f252/ ... feratu.gif

No idea, if it is correct...
I wonder why they call this pedal Mosferatu???? :slap:

roseblood11
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Post by roseblood11 »

freq67 wrote:
roseblood11 wrote:I just found this:

https://i49.photobucket.com/albums/f252/ ... feratu.gif

No idea, if it is correct...
I wonder why they call this pedal Mosferatu???? :slap:

?? Aren´t four Mosfet´s enough?

Angle Loss
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Post by Angle Loss »

roseblood11 wrote:I just found this:

https://i49.photobucket.com/albums/f252/ ... feratu.gif

No idea, if it is correct...
That is NOT correct. I believe that was some early incarnation of the Mosferatu which Hermida allowed people to see, but is not the final form at all. He has said in the past that the Mos and Zen are related and that the Mos was created on the way to the Zen.

Tom1884
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Post by Tom1884 »

Angle Loss wrote:
That is NOT correct. He has said in the past that the Mos and Zen are related and that the Mos was created on the way to the Zen.
So there isn't any dual gain stage... :scratch:

Angle Loss
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Post by Angle Loss »

It has been a long time since I have thought about this...so any corrections are welcome. :D As I recall, he gave that schematic out on another diy forum and said it was an earlier incarnation of the Mos. I believe it was shown to demonstrate something about a MOSFET clipping arrangement.

He goops his pedals, so I don't believe he would release any final schematic. From what I remember, then Mos has mosfets+germ diodes in anti-parallel in the negative feedback loop of the opamp like most overdrives. The Character control changes the pre-gain frequency structure in the negative feedback loop, and the tone control is similar to a Rat. I no longer have a Mos to tell you for sure...although maybe someone else here can chime in with confirmation or correction, but I do know that that schematic is not correct to the production Mos. I hope that helps.

Angle Loss
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Post by Angle Loss »

Forgot to mention, the schematic shows dual gain controls plus both post-gain treble and bass controls, which obviously the Mosferatu does not have.

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aflynt
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Post by aflynt »

Tikidrive ancestor maybe?

-Aaron

bigorangefan79
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Post by bigorangefan79 »

Mosfe(t clippers) ra(t tone control) tu(be screamer type) ... sounds like a zendrive... no really, it sounds like a zendrive.

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Post by bigorangefan79 »

If I were to guess I would say the Mosferatu is a Zendrive with mosfet clippers only. It definately has a little more gain.

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kusi
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Post by kusi »

from a de-goop-job in 2007...
Attachments
CIMG0017_klein.jpg
Hermida_Mosferatu.pdf
(47.61 KiB) Downloaded 675 times

Tom1884
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Post by Tom1884 »

kusi wrote:from a de-goop-job in 2007...
Thanks kusi! :applause:
But what is the reliability of this schematic?

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kusi
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Post by kusi »

this isn`t the first tubescreamer i traced.... ;)

Tom1884
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Post by Tom1884 »

kusi wrote:this isn`t the first tubescreamer i traced.... ;)
;)
I was looking at it... 2 things:
1) are there 4 pot in the pic? I can't see the second row...
2) what about the voice pot in the sch?

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kusi
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Post by kusi »

i traced the older 3-knob-version. "vioce" is just a variable resistor for R5 (lok at the zendrive)

about the other "mosferaut"-schematic, i asked alfonso some years agoo about it. his answer:
> That design has nothing to do with my commercial product. I just liked the
> name so much that I decided to use it in the unit that I make.


regards, kusi

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reneshelle
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Post by reneshelle »

I'm guessing here, but if you look at the voice pot on the zendrive and transfer that idea to the mosferatu, I don't think you're that far off...

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