Alright, I have a look at it. I thought the SU series amps were all fully integrated amps.
xrk971
Very nice cooling system for the amplifier.
Some day I must try some A-class myself, never build one so far.
Winter time there is about 5deg C in my office so I would really every aspect of Aclass would be highly recommended 😀.
Mile
The A40 spider looks really cool on the board.
regards
Pit
Very nice cooling system for the amplifier.
Some day I must try some A-class myself, never build one so far.
Winter time there is about 5deg C in my office so I would really every aspect of Aclass would be highly recommended 😀.
Mile
The A40 spider looks really cool on the board.
regards
Pit
Attachments
AA14 is simple class A amplifier it can give you idea for your class A amp.
Attachments
Hi Apex,
Well, comparing the published specs. this is a bit of a head scratcher. The SE-A7 sports the better specs, yet uses the same OPS and drivers as the SU-V7. I am not sure, using the same components, how the specs in particular the dampening factor can be so vastly different. Either the transistors were much improved over time or the SU-V7 has poor output conductivity or layout deficiencies. Altho the circuits seem very very similar, if not identical, I am puzzled on the specs been so different. Well, I played a bit with the simulation, it appears increasing the current through the input FETs does not seem to help improve the amp performance, it seems to worsen. However, doubling the current through the intermediate stage improved THD significantly, effectively halfing THD figure at 20kHz ! I admit, I am not sure what you mean by better DC offset. How much better than less of a millivolt is this going to get ?
Well, comparing the published specs. this is a bit of a head scratcher. The SE-A7 sports the better specs, yet uses the same OPS and drivers as the SU-V7. I am not sure, using the same components, how the specs in particular the dampening factor can be so vastly different. Either the transistors were much improved over time or the SU-V7 has poor output conductivity or layout deficiencies. Altho the circuits seem very very similar, if not identical, I am puzzled on the specs been so different. Well, I played a bit with the simulation, it appears increasing the current through the input FETs does not seem to help improve the amp performance, it seems to worsen. However, doubling the current through the intermediate stage improved THD significantly, effectively halfing THD figure at 20kHz ! I admit, I am not sure what you mean by better DC offset. How much better than less of a millivolt is this going to get ?
Attachments
That amp will clip with rounded corners and clamp saturations.
Will actually dissipate less when overloaded.
Nice.
OS
I have had a couple of productive months. First up an integrated amp based on the excellent Avondale Audio Qudos boards powered by a pair of Holden and Fisher toroids and 10,000uf at +- 45vdc. This will shortly be heading over to my daughters.
Secondly a pair of monoblocks based on the brilliant Avondale Audio NCC300 amp boards. These are for myself and I am very much enjoying the sound quality of these amps.
My Amp Camp Amp with toroidal transformer :
more info in my web site:
DIY ACA class A amplifier with linear power supply. - Audiophile Diyer
more info in my web site:
DIY ACA class A amplifier with linear power supply. - Audiophile Diyer
Hi Hicoco; the transformers are AST fully potted with dual centre tapped secondaries which are connected in parallel for the NCC300's.
These were bought from Les Wolstenholme of Avondale Audio. I have no connection with the company other than as a satisfied customer.
These were bought from Les Wolstenholme of Avondale Audio. I have no connection with the company other than as a satisfied customer.
Last edited:
Good Idea , I might buy a "parts or repair" EBAY unit for my "greenamp'.
Even a pro amp with fan/tunnel , class H will very rarely need the fan to
run.
Pro amp might even have the dual secondary trafo (for H/L rails).🙂
OS
Each time I built amp, it's the chassis work that took the longest to finish. By using already finished chassis (with only a few holes to drill), it makes DIY-ing simpler. 
Just tought I'd share some pictures of Fab's new Class AB FSSA-2 amplifier.
It is a CFA amplifier, powered with +/-45Vdc and should be able to give me about 100W on 8 ohms.
This one does not use any exotic parts except maybe the 2SK170/J74 which are still available. Most resistors are Takman Metal Film and a couple PRP, some Mills MRA-5, Caddock, etc...
All the best!
Do
It is a CFA amplifier, powered with +/-45Vdc and should be able to give me about 100W on 8 ohms.
This one does not use any exotic parts except maybe the 2SK170/J74 which are still available. Most resistors are Takman Metal Film and a couple PRP, some Mills MRA-5, Caddock, etc...
All the best!
Do
Last edited: