I have had to make some decisions about what or how many amps I need to have in the house...🙂 the present count is over 11 power amps of various sorts and this is the latest project I completed only a few weeks ago. This is a First Watt F6 clone (via the DIYaudio store), the PCBs for the power supply and the amp boards 'ki't and all the jfets/Mosfets where purchased from the DIY store so are perfectly matched for the amp. The case is also a DIYaudio purchase the 5U deluxe (pre drilled) which is over the top for this amp but its one I had doing nothing for a while so I put it to good use (it has been used before so some slight marks but nothing nothing to worry about.) All the components where soured from either Mouser/RS or Farnell.
The LED's on the from panel are blue. (Its not powered up in this shot....)
All the specs are available all over the net or at DIYaudio. But in short its a pure Class A amp which produces 25watts per channel.
It was built to Nelson Pass's schematic and power supply requirements + the 6.2v zener ref diodes have been replaced for the 3 LED's upgrade for quieter operation as specified on the forum. Which does make a nice lift.
Each channel has its own transformer which are 250VA with 18 -0 -18 secondaries which relates to supplying 24vDC to the power amp modules.
The bias is set to 0.8mV per device so a total of 1.6amps per channel and 50-55 deg C at the heat sinks after some hours of running.
I have also fitted a Vellman speaker protection circuit just for peace of mind..
An audition would normally be possible but at this time might be best not to offer this option. Though I'm only offering collection or buyer arranges own shipping (I do not have a box, it is very heavy) so might be able to arrange a listen.
This is a superb sounding amp, sweet and detailed 'a valve' like presentation its said.
£900
PM please
The LED's on the from panel are blue. (Its not powered up in this shot....)
All the specs are available all over the net or at DIYaudio. But in short its a pure Class A amp which produces 25watts per channel.
It was built to Nelson Pass's schematic and power supply requirements + the 6.2v zener ref diodes have been replaced for the 3 LED's upgrade for quieter operation as specified on the forum. Which does make a nice lift.
Each channel has its own transformer which are 250VA with 18 -0 -18 secondaries which relates to supplying 24vDC to the power amp modules.
The bias is set to 0.8mV per device so a total of 1.6amps per channel and 50-55 deg C at the heat sinks after some hours of running.
I have also fitted a Vellman speaker protection circuit just for peace of mind..
An externally hosted image should be here but it was not working when we last tested it.
An audition would normally be possible but at this time might be best not to offer this option. Though I'm only offering collection or buyer arranges own shipping (I do not have a box, it is very heavy) so might be able to arrange a listen.
This is a superb sounding amp, sweet and detailed 'a valve' like presentation its said.
£900
PM please
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