Hello everyone. Some weeks ago I posted with some questions regarding the use of the 5763 in audio, specifically guitar, amplifier circuits, and with those questions resolved by the very helpful members of this forum, promised to post some documentation of the completed circuit at some point in the future. That point is now, as the amplifier works and has now been safety tested. It uses a 6AU6 in the preamp, and the 5763 in the power amp (the tube I have is actually an 5763-equivalent Philips QE03/10). Here is the schematic:
And here are some photos:
I used a baking tray for the chassis, which was quite effective. This is my first tube amplifier build.
I cannot claim very much credit at all for its design, it being essentially an amalgamation of segments of existing circuits, but I thought the schematic might be helpful to anyone interested in using 5763 or 6AU6s in a guitar amplifier application. The preamp section is taken directly from the Halogen Heptal design described here, and the power supply from the Valve Heaven Solo design, available here, from the same designer, Grant. The power amp is built according to this datasheet’s documentation of a typical audio frequency application of the 5763 (on page 4, I used the second column of values). The output transformer is a halogen downlight 240V-12V stepdown mains transformer, another idea I borrowed from Grant of Valve Heaven. Likely not an optimal option for tone, but functional and very cheap.
I think it sounds quite reasonable, and I imagine it would sound better if played through a nicer speaker than the 6” solid state practice amp sourced number I’m currently using. There is also very little hum, certainly not enough to be noticeable in normal playing.
I recorded a short demo for any interested parties, using a Squier Affinity Tele and a Shure SM57 into a Steinberg UR22, that should be available here.
So, for those interested, I can confirm that the 5763 does work in a guitar amplifier circuit, and with reasonably satisfactory results (by my measure).
And here are some photos:
I used a baking tray for the chassis, which was quite effective. This is my first tube amplifier build.
I cannot claim very much credit at all for its design, it being essentially an amalgamation of segments of existing circuits, but I thought the schematic might be helpful to anyone interested in using 5763 or 6AU6s in a guitar amplifier application. The preamp section is taken directly from the Halogen Heptal design described here, and the power supply from the Valve Heaven Solo design, available here, from the same designer, Grant. The power amp is built according to this datasheet’s documentation of a typical audio frequency application of the 5763 (on page 4, I used the second column of values). The output transformer is a halogen downlight 240V-12V stepdown mains transformer, another idea I borrowed from Grant of Valve Heaven. Likely not an optimal option for tone, but functional and very cheap.
I think it sounds quite reasonable, and I imagine it would sound better if played through a nicer speaker than the 6” solid state practice amp sourced number I’m currently using. There is also very little hum, certainly not enough to be noticeable in normal playing.
I recorded a short demo for any interested parties, using a Squier Affinity Tele and a Shure SM57 into a Steinberg UR22, that should be available here.
So, for those interested, I can confirm that the 5763 does work in a guitar amplifier circuit, and with reasonably satisfactory results (by my measure).
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I've just discovered you can't edit your post more than 30 minutes after posting. Here's the fixed schematic:
Also, in the schematic the 100k potentiometer voltage divider on the screen should be set so that voltage on the screen is 225V, I should've explained that in my original post.
Also, in the schematic the 100k potentiometer voltage divider on the screen should be set so that voltage on the screen is 225V, I should've explained that in my original post.
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Good project. Now for a homemade head shell with matching cabinet.
Ps. The much-maligned budget Celestion 'Rocket 50' 12" guitar speaker can often be picked up for chump-change on eBay. A perfect partner for a budget amp and vastly improved tone over any 6" speaker. (I paid NZD80.00 for 4).
Ps. The much-maligned budget Celestion 'Rocket 50' 12" guitar speaker can often be picked up for chump-change on eBay. A perfect partner for a budget amp and vastly improved tone over any 6" speaker. (I paid NZD80.00 for 4).
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