Circuit of Musical Fidelity A1, Any one has experiences?

[siliconray]

Just saw a circuit of Musical Fidelity A1 power amplifier. No part number of the transistors. Any one has experience wit this amp? I'd like to know the part no. of transistors, thanks

 

[Tekko]

Pretty standard circuit, the transistors are likely something like BC547 and BC557 and the power transistors are prolly some obsolete 2SCxxxx like the 3284 and 1302 or similar.

At only 2x18V rails, pretty much any transistors would work.

 

[siliconray]

Thanks Tekko, will build one soon

 

[gfle]

http://www.tcaas.btinternet.co.uk/mf-a1.gif

 

[raymondo]

I'm sure the power devices were 2n3055 .
There's a guy who used to work for
Mf on here who could tell u for sure.

 

[Tekko]

Which are no good for audio so replace with MJL3281 and MJL1302

 

[siliconray]

It seems that 2N3055 are not recommended for used in audio now. It's too old and too slow. In another thread about JLH amplifier many suggest MJL15003 as subsititute

 

[jez]

I'm sure the power devices were 2n3055 .
There's a guy who used to work for
Mf on here who could tell u for sure.

I am that guy 😉
They used 2n3055 and mj2955 complementary pairs which were labelled A1N and A1P.

 

[Bigun]

Whilst 2N3055 are no longer considered state of art and there are better devices available I believe many people have used them and been very happy with the results. If I were building a classic amp like this, I'd want to start off with devices as close to the originals as possible - otherwise I'm going to be hearing a different amp.

 

[jez]

The mj15003/15004 were used in the more powerful A100 (which is the same circuit) and will work well in the A1 also.