I am having a clear out and as I am committed to a DSP driven system, I have no use for my valve pre-amp. Being lazy follow the link to the advert on DIYA.
http://www.diyaudio.com/forums/swap-mee ... e-amp.html
FS - Pre-amp with output Transformers
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- Old Hand
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- Paul Barker
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#2 Re: FS - Pre-amp with output Transformers
Shame your lazy because I cant open the jpegs on your link without joining.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
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- Old Hand
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#3 Re: FS - Pre-amp with output Transformers
Lazy, was an excuse for my ignorance of being able to make the pictures I took on my iPad smaller in size so I can post them on the forum.
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- Old Hand
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#4 Re: FS - Pre-amp with output Transformers
Sorted it so here's the full advert..... can only seem to post 3 pictures though
Up for sale is a preamp based on the design of troels gravesen, see link TRAM w.
Reason for sale is I have moved to a fully active system now using a DSP so this preamp is redundant and has been sitting in the cupboard. It had a very typical with output transformers sound, used with some 6B4G amps feeding very efficient horns - low background noise, even when feeding 114db efficient speakers.
My version is based arround Bartolucci output transformers. I used a solid state HT power supply with regulation via a Salas Shunt board. The volume control is via a 30 increment stepped attenuators, around a shallco style switch, to with the resistors are directly soldered to it.
I used kiwame resistors, a obligato film capacitor and silver mica resistors in the circuit along with the 2 watch batteries per channel.
It is built on two chassis's keeping the PSU separated connected via a multi pin military connector, the psu is in a metal chassis. The preamp was built to show, with a stainless steel chassis to which all is bolted, in an oak plinth. As well as the transformers and teflon valve sockets, there is a copper plate, verdigris finish (attached to as focused heat sink for shunt regulator) On the front are two knobs ( industrial looking - can be easily changed to match you style) for volume control and input selection - currently wired for two inputs, holes for a third pair of rca's is provided on the back. All the rca's used are silver plated CMC ones. Two additional redundant holes in front panel, (easily covered by a plaque etc).
It is in full working order and its sound will make you forget about it's looks industrial looks. Comes with a number of 6n6p valves, you and mix and match the best pair from them. One picture shows the circuit I used, not including the valve power supply, a total of 2 resistors and 2 capacitors in the signal path.
My price is based around the cost of the transformers and the volume control. £400 This is a heavy amp, due to having 4 transformers. The preamp weights 10kg and the psu weights 5 kg. Postage will be at cost.
Up for sale is a preamp based on the design of troels gravesen, see link TRAM w.
Reason for sale is I have moved to a fully active system now using a DSP so this preamp is redundant and has been sitting in the cupboard. It had a very typical with output transformers sound, used with some 6B4G amps feeding very efficient horns - low background noise, even when feeding 114db efficient speakers.
My version is based arround Bartolucci output transformers. I used a solid state HT power supply with regulation via a Salas Shunt board. The volume control is via a 30 increment stepped attenuators, around a shallco style switch, to with the resistors are directly soldered to it.
I used kiwame resistors, a obligato film capacitor and silver mica resistors in the circuit along with the 2 watch batteries per channel.
It is built on two chassis's keeping the PSU separated connected via a multi pin military connector, the psu is in a metal chassis. The preamp was built to show, with a stainless steel chassis to which all is bolted, in an oak plinth. As well as the transformers and teflon valve sockets, there is a copper plate, verdigris finish (attached to as focused heat sink for shunt regulator) On the front are two knobs ( industrial looking - can be easily changed to match you style) for volume control and input selection - currently wired for two inputs, holes for a third pair of rca's is provided on the back. All the rca's used are silver plated CMC ones. Two additional redundant holes in front panel, (easily covered by a plaque etc).
It is in full working order and its sound will make you forget about it's looks industrial looks. Comes with a number of 6n6p valves, you and mix and match the best pair from them. One picture shows the circuit I used, not including the valve power supply, a total of 2 resistors and 2 capacitors in the signal path.
My price is based around the cost of the transformers and the volume control. £400 This is a heavy amp, due to having 4 transformers. The preamp weights 10kg and the psu weights 5 kg. Postage will be at cost.
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- Old Hand
- Posts: 1081
- Joined: Sat Jan 26, 2013 12:08 pm
#5 Re: FS - Pre-amp with output Transformers
Sold elsewhere, gone to China