Hi all,
It's 2017 now. I am trying to make a Goldmund wiki that collects information I got from the internet. I hope this will be a great review for new builders.
***2017/09/07***
Reference schematic available!
http://www.diyaudio.com/forums/attachment.php?attachmentid=633063&d=1504260890
*****Kept updating*******
2017/3/17 Google site ON AIR!
Goldmund 2017
VAS:
2n5564/NPD5564 no significant difference
Output:
10N20/10P20 from Exicon is far more better than 2SK1058/J162, more punchy bass.
**********
"The Telos basically same as Mimesis, except some points:
- LTP Iq is higher, same 4.3mA. The 6V zener of Mimesis instead by LM329 precision low noise 6.9V zener.
- VAS Iq a bit smaller, same 7.8mA for both sides. VAS devices are Zetex transistors, FZT957/FZT857 SOT 223 SMD.
- Individual driver (MJE340/MJE350, but they're KSC2690A/KSA1220A for Telos 5000) for each MOSFET output pair(Exicon ECX10N20/10P20). There are six pairs output per channel.*
Based on this info, you can transform Mimesis to Telos."
It's 2017 now. I am trying to make a Goldmund wiki that collects information I got from the internet. I hope this will be a great review for new builders.
***2017/09/07***
Reference schematic available!
http://www.diyaudio.com/forums/attachment.php?attachmentid=633063&d=1504260890
*****Kept updating*******
2017/3/17 Google site ON AIR!
Goldmund 2017
VAS:
2n5564/NPD5564 no significant difference
Output:
10N20/10P20 from Exicon is far more better than 2SK1058/J162, more punchy bass.
**********
"The Telos basically same as Mimesis, except some points:
- LTP Iq is higher, same 4.3mA. The 6V zener of Mimesis instead by LM329 precision low noise 6.9V zener.
- VAS Iq a bit smaller, same 7.8mA for both sides. VAS devices are Zetex transistors, FZT957/FZT857 SOT 223 SMD.
- Individual driver (MJE340/MJE350, but they're KSC2690A/KSA1220A for Telos 5000) for each MOSFET output pair(Exicon ECX10N20/10P20). There are six pairs output per channel.*
Based on this info, you can transform Mimesis to Telos."
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schematics
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Thanks guys.
I am doing my own Goldmund ver.3, and I am planning to make a ver.4 with discrete VAS module.
If you have something related and important about Goldmund, please upload them and we can enjoy!😉
I am doing my own Goldmund ver.3, and I am planning to make a ver.4 with discrete VAS module.
If you have something related and important about Goldmund, please upload them and we can enjoy!😉
Hi all,
I have questions about choosing current mirror BJTs.
Some options:
1. discrete MPSA42----inexpensive
2. DMMT5551----matched, dual, SMD
3. MMDTA42---- unmatched, dual , SMD
I'd prefer DMMT5551, because it's matched though lower Vcbo.
Any problems will I meet if I chose DMMT5551?
and, is MMDTA42 better than MPSA42?
thanks
I have questions about choosing current mirror BJTs.
Some options:
1. discrete MPSA42----inexpensive
2. DMMT5551----matched, dual, SMD
3. MMDTA42---- unmatched, dual , SMD
I'd prefer DMMT5551, because it's matched though lower Vcbo.
Any problems will I meet if I chose DMMT5551?
and, is MMDTA42 better than MPSA42?
thanks
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I don't see why there would be problems. The 5551/5401 are a much better pair technically, but if the popular sound of the Goldmund has to do with the coloration of the MPSA92/42, then it may affect whether you like the result.
Would this be like for like MOSFETs, i.e., 8 Amp 2SK vs. 8 Amp Exicons, or would that be the double die 16 Amp Exicons?
8 Amp 2SK vs. 8 Amp Exicons. I don't have double die Exicons.
2SK and Exicons are similar (or not that noticeably different) at mid-high, but substantial difference at bass!
It's punchy, vivid bass.
I never go back to 2SK/2SJ after that trial, always Exicons, though much more expensive.
BTW, I use plastic TO-247 10N20/10P20.
Best,
Eric
Thanks, that's interesting and disappointing as I have 64 each of 2SJ162 / 2SK1058 in the drawer in preparation for making 4 amplifiers.
Do know if the Execons are the same as the Semelab Alfets?
Do know if the Execons are the same as the Semelab Alfets?
Well, I'd say it's not that bad 🙄
2SK/2SJ is "good" based on the Goldmund circuitry, and if cost-effectiveness is considered, they're good options.
Just suggesting "better" transistors IMHO, while 2SK/2SJ are also good. 🙂
It could be worse, I could have fitted them all already. 🙂 I guess I have to get a set of Execons and compare them. I fitted Alfets in another amp a year ago but they were TO3 and my heat sinks are made for TO3P, etc., so I couldn't compare them, only the amps, the 'standard' Hitachi clone amp, circa 1983, was not in the same league as the amps the 2SJ161 / 2SK1057 which were modified Meridian 605's, but it's not a like for like as the PSU's, wiring, other components, etc, were so different. I'd like to compare circuit vs. circuit with PSU's, etc, the same.
Here I found a Mimesis 27 preamp schematic.
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OK, here it is.
This is the latest version I've developed, it's named G29.4 Lux-Dual.
It's actually the 4th generation of my Goldmund based on Mimesis 29.4 . Because I thought the tech and knowledge is matured, I decided to make this 4th generation G29.4-LD gold-plated (way more expensive....). I just got these PCBs several weeks ago, yet don't have time to finish them.
Input stage:
It's compatible with:
1. 2SK170 * 2
2. NPD5564, DIP-8
3. 2N5564, TO-71
4. SSM2212, super-matched BJTs, SOIC-8
Output
2 pairs at output
Other
PCB 138*63mm, gold-plated
This is the latest version I've developed, it's named G29.4 Lux-Dual.
It's actually the 4th generation of my Goldmund based on Mimesis 29.4 . Because I thought the tech and knowledge is matured, I decided to make this 4th generation G29.4-LD gold-plated (way more expensive....). I just got these PCBs several weeks ago, yet don't have time to finish them.
Input stage:
It's compatible with:
1. 2SK170 * 2
2. NPD5564, DIP-8
3. 2N5564, TO-71
4. SSM2212, super-matched BJTs, SOIC-8
Output
2 pairs at output
Other
PCB 138*63mm, gold-plated
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