Hello to all,
Sorry to interrupt, I been following the thread from first to this point to cope with this project, very interesting!!!
@obiwankenobi
How your board going?
I'd trace the schematic and board layout you've posted including the protection circuit Nagys sent you it's truly the Mimeses 3, it is also same schematic and layout posted by Nagys in its new thread after lift here, it seems correct if base on hand drawn and updated protection schematic, the only problem is the orientation of electrolytic capacitors in protection circuit seems confusing, but i'll try to figure this out.
I Nagys sent this board and schematic we can assume that it might work without modifying the board, you might be the first to make this Mimeses 3 if that happen.
I'll try to gather parts and layout this Mimesis 3 so I could catch up with you. Hope you could post updated of your progress here.
Regards to all,
Angeltech
Sorry to interrupt, I been following the thread from first to this point to cope with this project, very interesting!!!
@obiwankenobi
How your board going?
I'd trace the schematic and board layout you've posted including the protection circuit Nagys sent you it's truly the Mimeses 3, it is also same schematic and layout posted by Nagys in its new thread after lift here, it seems correct if base on hand drawn and updated protection schematic, the only problem is the orientation of electrolytic capacitors in protection circuit seems confusing, but i'll try to figure this out.
I Nagys sent this board and schematic we can assume that it might work without modifying the board, you might be the first to make this Mimeses 3 if that happen.
I'll try to gather parts and layout this Mimesis 3 so I could catch up with you. Hope you could post updated of your progress here.
Regards to all,
Angeltech
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Hello NagysDesign welcome back.
I have 4 mono blocks ready to fir up. telos.
you have some tips for what and where to measure.
maybe separate pcbs?
I have stuffed the boards full. want to try the front end to
do I need the rectifier 15VAC if I use power from -veeb and +vcc?
in pre r24 is 560 Ohm?
I'm using 2x 55v trafo 1000Va rest is according to drawing
output is 8pair 2sk1058 and 2sj162
r19 =330 ohm
r5-8=100 ohm
r9-11=220c ohm
this sound ok?
maybe a problem with diodes 2,3,4,5 ??? should I skip them? something about the biasing?? read it somewhere i think.???
I have 4 mono blocks ready to fir up. telos.
you have some tips for what and where to measure.
maybe separate pcbs?
I have stuffed the boards full. want to try the front end to
do I need the rectifier 15VAC if I use power from -veeb and +vcc?in pre r24 is 560 Ohm?
I'm using 2x 55v trafo 1000Va rest is according to drawing
output is 8pair 2sk1058 and 2sj162
r19 =330 ohm
r5-8=100 ohm
r9-11=220c ohm
this sound ok?
maybe a problem with diodes 2,3,4,5 ??? should I skip them? something about the biasing?? read it somewhere i think.???
Hello RickDangerous,
Base on first post of schematic its the same parts number or value, when you look at on neg. supply rail regulator circuit except reverse the polarity. to be specific its the rectifier diode 1N4004.
I thinks the schematic was cut during scanning or something...
regards,
Angeltech
Base on first post of schematic its the same parts number or value, when you look at on neg. supply rail regulator circuit except reverse the polarity. to be specific its the rectifier diode 1N4004.
I thinks the schematic was cut during scanning or something...
regards,
Angeltech
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Not sure which Goldmun Clone tread is still active so I'll post here and see. I've was reluctant to try to build one of these because of all the "discussions" over the past 3 years on the "right" schematic or PCB etc etc. I did want to compare it to other DIY amps like a TO3 SymaSym and FC100. Its been a long winter so I gave in and made a V3.9 PCB. After populating the amp side only with as many original parts as I could find, the first power up was tentative: the amp seemed to work okay at 50V rails but gave an oscillating DC offset when connected to output - adjustment was fine with no input or output. Tried all kinds of things to cure this but nothing as worked so far. The sound from amplifier into a cheap test speaker seems okay!!!
Of course, on populating the protection circuit side, all I get when connecting the speaker is the relay cycling on and off. It goes on okay without the output connected. I am stumped, any ideas as to the source of the problem???
Of course, on populating the protection circuit side, all I get when connecting the speaker is the relay cycling on and off. It goes on okay without the output connected. I am stumped, any ideas as to the source of the problem???
hello. email from member Vitali and this amp is up and running.
Hi Stig,
This amp is worth the effort.
It is the best sound that I heard him!
Transistors,resistors - Exactly like in the schematics!
R20 - 330R (biass 100mA)
T5-T6 -Contact thermal!
T7-T8-T9-T10 - Thermal contact all four together!( I did exactly as proposed by Nikos on diyaudio)
Otherwise offset will not be stable!
I'm on the board:
C3=4,7PF
C5 = 10PF
C6 = 4,7PF
C7 = 4,7PF
T7 between B-C: 4,7PF
With these capacitors is perfect signal on the oscilloscope.
Transformers : 2x50V/500W (2 bridges for channel) It is the same 2x50V /500mA for BD249/BD250
From the bottom PCB - 2x 10000/100V.
On PCB - 2x4700/100V.
Not use strong resistors in the source.
Good luck !
Excuse my English
Best regards,
Vitali
Hi Stig,
This amp is worth the effort.
It is the best sound that I heard him!
Transistors,resistors - Exactly like in the schematics!
R20 - 330R (biass 100mA)
T5-T6 -Contact thermal!
T7-T8-T9-T10 - Thermal contact all four together!( I did exactly as proposed by Nikos on diyaudio)
Otherwise offset will not be stable!
I'm on the board:
C3=4,7PF
C5 = 10PF
C6 = 4,7PF
C7 = 4,7PF
T7 between B-C: 4,7PF
With these capacitors is perfect signal on the oscilloscope.
Transformers : 2x50V/500W (2 bridges for channel) It is the same 2x50V /500mA for BD249/BD250
From the bottom PCB - 2x 10000/100V.
On PCB - 2x4700/100V.
Not use strong resistors in the source.
Good luck !
Excuse my English
Best regards,
Vitali
Hi,
Your comments about comparing the different DIY amps in this and other DIY forums made me jump to the keyboard, as I did excatly this.
I made a loudspeaker system described here: http://www.diyaudio.com/forums/multi-way/193015-stupid-cheap-line-array-22.html
and it was so good and revealing of what was before it, that I decided to make a bunch of the DIY amps with best reputation. I had made an OTL with 6C33 and this was the amp to beat...
So these amps were made:
The amazing FET circlotron
Another circlotron schematic described in the fet circlotron thread with lateral as sourcefollower output and ths4131 diff. opamp.
The First Watt F5
The Roender FC100
The Swordfish/aksa fet/mosfet/lateral with battery supply (and conventional PS)
The Bow Technologies ZZ1 improved (this is not a described DIY project, but I was part of the development team to make this)
The Audio Mirror TFA3 Hybrid tube /mosfet (an old design by me in 1984)
The Moskido
Hypex Class D 180/400/700 conventional ps and battery and descrete front end.
ALL of these amps are very good amps with their own strenghts and weaknesses, but overall the OTL was the one I kept returning to.
UNTIL TA_DAAAH
I made the Quanghao clone of the Goldmund Telos amp.This is the champion now!
It is so transparent, powerfull, delicate and has a soundstage to die for!!
I find it very strange, as the topology is not that special. It is a rather conventional feedback amplifier with diff. input VAS and lateral MOSfet out, though in the Telos version there is a driver per MOSfet in the output, but nevertheless , I have found MY amplifier.
Just my 25c
Koldby
koldby - You have traveled a path quite similar to mine. I started with the RC version of Dario Inserra's MyRef Fremen Edition and built several amps for comparison. Though not as extensive as your collection, my experiences dictate that I must propose you haven't yet heard "The Best" (whatever that means ) of what DIY can produce.
If you still have some time, interest and leftover solder, I invite you to keep an eye on the Final Edition Build Thread and consider participating in an upcoming second group buy. So far, that phrase "Best I Have heard" has come from all the current builders of Mr. Inserra's efforts.
Would love to hear your impressions if and when you take up this friendly challenge
A
) of what DIY can produce.If you still have some time, interest and leftover solder, I invite you to keep an eye on the Final Edition Build Thread and consider participating in an upcoming second group buy. So far, that phrase "Best I Have heard" has come from all the current builders of Mr. Inserra's efforts.
Would love to hear your impressions if and when you take up this friendly challenge
A
koldby - You have traveled a path quite similar to mine. I started with the RC version of Dario Inserra's MyRef Fremen Edition and built several amps for comparison. Though not as extensive as your collection, my experiences dictate that I must propose you haven't yet heard "The Best" (whatever that means
If you still have some time, interest and leftover solder, I invite you to keep an eye on the Final Edition Build Thread and consider participating in an upcoming second group buy. So far, that phrase "Best I Have heard" has come from all the current builders of Mr. Inserra's efforts.
Would love to hear your impressions if and when you take up this friendly challenge
A
Correct me if I am wrong... This is another version of a GainClone Right?
And I have made amplifiers with lm3886. I know a lot of people are very fond of these amps, but I am not impressed by them. It is almost the same as the legendary Le Monstre by Jean Hiraga. There was a lot of people who sweared to that design, but to my ears it was seriously flawed.
And lm318 as op amp. Are you serious?
Well you never know and maybe I should try it out anyway.
Thanks for the suggestion.
By the way : have YOU tried the Goldmund Telos clone?
Koldby
but rather a sort of current dumping topologi, so maybe it has potential afterall...
Koldby,
I'm another one of those MyRef Fremen Edition fans. I don't have your range of experience, but I certainly like the FE. Accepting that different people like different things, could you point more specifically at the Telos clone you are referring to? I did a search and found several efforts, but not Quanghao clone you mentioned. I would be interested in studying it.