Somebody was talk about Hiraga single-ended Némésis in this thread
i was curious and find today audiophile who sell his genuine monoblockswith Tango output trasformers
for 2k8 € in France. Not my budget but pleasure to see on colours photos.
Nice design with CLC filtered psu
Attachments
Hello,
This amp has the choke that i did use for my Hiraga 30 watt amp. Now of course you can get the Lundahl LL1694 and LL 2733 which offer probably better filterinmg because of the way they are constructed. The choke in the nemesis amp was just a very ordinary one. Probably 95% of the companies that make transformers can make you a similar or better one.
At that time people did not shop all over the world.
Greetings, Eduard
This amp has the choke that i did use for my Hiraga 30 watt amp. Now of course you can get the Lundahl LL1694 and LL 2733 which offer probably better filterinmg because of the way they are constructed. The choke in the nemesis amp was just a very ordinary one. Probably 95% of the companies that make transformers can make you a similar or better one.
At that time people did not shop all over the world.
Greetings, Eduard
Here is the link from a local DIY forum.
Amplificateur USSA 15W - Conception
p.s. Google translate is your friend.
BR,
Eric
Here is a crazy idea to try. Mr Hiraga was always intrigued by Hafler amps. Perhaps you could borrow an old one and have a listen. Plenty of power, should be stable into the dual panels. You never know.
Yes it was, I readed this several times in his reviews in La Nouvelle Revue du Son.... He said the crossing of the two transistors in class AB with the htrans-nova patent was not hearable : he liked the equilibrium on the more powerfull P900 (?) for difficult loads as well (neutral, not colored) ? and the transparency of the litle TA1600 ! (HAFLER TA 1600 ) !
The P900 was in La Nouvelle Revue du Son as one of the amps to review the speakers !
@ Fortier : aie aie : the author prefer the Class A hiraga to his Pass F5 but says, and his wife as well, than the USSA beats the Class A by a good margin !
Ah the big Brown cas seem the sames than in a famous brand of North Europe with its Nemo
!Could be fun to benchmark the USSA with this : http://www.diyaudio.com/forums/class-d/276982-tpa3251d2.html#post4386759
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Ok, so i did the voltage test on 220Hz:
With normal listening volume it is 4.7 volts. When I crank it up to a little higher, it rapidly goes to 8 Volts. Shortly after this, if I go further, it becomes unmeasurable. I am glad my Hiraga clips so nicely
These panels love to eat Voltage!
So, now I know for a fact I need more power! Al least 70 Watts RMS in Class A to play loud on my panels. My Hiraga is only 38 Watts. This is why I need something bigger with the same sound quality!
With normal listening volume it is 4.7 volts. When I crank it up to a little higher, it rapidly goes to 8 Volts. Shortly after this, if I go further, it becomes unmeasurable. I am glad my Hiraga clips so nicely
These panels love to eat Voltage!
So, now I know for a fact I need more power! Al least 70 Watts RMS in Class A to play loud on my panels. My Hiraga is only 38 Watts. This is why I need something bigger with the same sound quality!
Yep.... but only when 9+volts is applied so not common. They will do between 2 and 6 Ohms normally.
Difficult load, I know. But it is possible. Hence my question to all members in this thread.
I have some good ideas now. The first try is going to be the Ovation-NX amp. It looks good and I think it can do the job.
Difficult load, I know. But it is possible. Hence my question to all members in this thread.
I have some good ideas now. The first try is going to be the Ovation-NX amp. It looks good and I think it can do the job.
My Hiraga schematics
Pano,
See attachment. This is the schematic of my Hiraga. I changed Q5 and Q6 in 2SA634 and 2SC1096 Original NEC ones. C4 is 220p instead of 2200p. Q7 and Q8 are Original Toshiba's 1943 and 5200 PNP/NPN ones. C15 and C16 are bypassed with PIO's. Rest is all Silver/Mica exept for C9 and C10, those are 68p ceramics.
Rail voltage is 30.4VDC.(2 x 22VAC toroid)
So, what could be improved?
Pano,
See attachment. This is the schematic of my Hiraga. I changed Q5 and Q6 in 2SA634 and 2SC1096 Original NEC ones. C4 is 220p instead of 2200p. Q7 and Q8 are Original Toshiba's 1943 and 5200 PNP/NPN ones. C15 and C16 are bypassed with PIO's. Rest is all Silver/Mica exept for C9 and C10, those are 68p ceramics.
Rail voltage is 30.4VDC.(2 x 22VAC toroid)
So, what could be improved?
I really don't know, as I like to say : my ears are as great as my knowledge is poor ! Do you talk about CLC filtering in lieu of R11/12 ?
Tried PSUII free soft !
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