Hello,
I'm interested in building a clone of TVA1 - Michaelson and Austin, using a new layout. The attached file contains the new layout. I did a test with this model and now I will send for board production.
The board is double-sided and electrolytic capacitors will be fixed from the bottom side of the plate. All other components on top. The supply for the filaments of the tubes will also be at the top.
Would like some suggestions regarding the layout and whether there is any visible problem which can degrade the sound quality.
Regarding the use of pcb is a personal choice. I will use the Hashimoto transformers, which have already been purchased directly from Japan
Any feedback is welcome.
I'm interested in building a clone of TVA1 - Michaelson and Austin, using a new layout. The attached file contains the new layout. I did a test with this model and now I will send for board production.
The board is double-sided and electrolytic capacitors will be fixed from the bottom side of the plate. All other components on top. The supply for the filaments of the tubes will also be at the top.
Would like some suggestions regarding the layout and whether there is any visible problem which can degrade the sound quality.
Regarding the use of pcb is a personal choice. I will use the Hashimoto transformers, which have already been purchased directly from Japan
Any feedback is welcome.
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The prototype is working ...
Yesterday I finished the 3rd prototype. To use the power until the final design is ready, I mounted the amp on a chassis that was here at home. Actually, it was going to scrap in the garbage. Then I decided to mount the amplifier on it. Below are some photos of the power amplifier.
The sound is wonderful. And, at this moment, the otp is not the Hashimoto transformers. They are too big to be used on this chassis.
Now, I've already sent the board to the factory. I just want a professional look for this amplifier.
I'll post all the step-by-step, component lists, etc ... for this project. The sound of this unit is really very good.
Yesterday I finished the 3rd prototype. To use the power until the final design is ready, I mounted the amp on a chassis that was here at home. Actually, it was going to scrap in the garbage. Then I decided to mount the amplifier on it. Below are some photos of the power amplifier.
The sound is wonderful. And, at this moment, the otp is not the Hashimoto transformers. They are too big to be used on this chassis.
Now, I've already sent the board to the factory. I just want a professional look for this amplifier.
I'll post all the step-by-step, component lists, etc ... for this project. The sound of this unit is really very good.
An externally hosted image should be here but it was not working when we last tested it.
Looks like a great project !
A few questions about the PCBs:
Which layout program did you use ? Are you willing to share
the layout (the original files, because pdf is not so well
suited if you have the manufactured) or would you sell PCBs ?
I see you have both channels on one board, is it possible
to cut the board in two halves if one wants to make mono blocks ?
A few questions about the PCBs:
Which layout program did you use ? Are you willing to share
the layout (the original files, because pdf is not so well
suited if you have the manufactured) or would you sell PCBs ?
I see you have both channels on one board, is it possible
to cut the board in two halves if one wants to make mono blocks ?
Yes, it is a great project. Take a look at this link:
http://youtu.be/Bn2U7qfUC_w
I used Eagle software and after testing final project, I will post the geber files here. The channels are designed to operate in separated circuits including earth. It is possible to cut the board into two halves for the construction of mono blocks, with no problems.
pcb double-sided
The images below are of the pcb double-sided. In the final project I will use DC for tube hearts, with the tube sockets mounted on the bottom of the board in inverted position. The hum level is excellent.
In this project I included a soft starter and delay circuit to the B + (550v). The chassis I would like to use was this:
2U Slimline (Tube-Friendly Configuration) - Full Width with Quasi Heatsinks - Chassis
.. but it is out of the stock. So I bought this one:
Model AL-470R-S
The images below are of the pcb double-sided. In the final project I will use DC for tube hearts, with the tube sockets mounted on the bottom of the board in inverted position. The hum level is excellent.
In this project I included a soft starter and delay circuit to the B + (550v). The chassis I would like to use was this:
2U Slimline (Tube-Friendly Configuration) - Full Width with Quasi Heatsinks - Chassis
.. but it is out of the stock. So I bought this one:
Model AL-470R-S
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So in the final version the tube sockets are mirrored, right ?
From various other posts on the net there seem to be some
confusion about the correct schematic, did you see this post:
http://www.diyaudio.com/forums/tubes-valves/123806-michaelson-austin-tva-1-info.html
Would you sell some PCBs too ? (The current version, like in your picture
would be ok for me).
Yes, your are right: sockets on bottom, components on top and pcb in inverted position relative to chassis. I'm in a process of soldering the components in new pcb and as soon as I can I will upload a picture to show that.
I saw the entire post. It has a lot of information. But I used this schematic:
http://www.diyaudio.com/forums/tubes-valves/173455-revamping-michaelson-austin-tva-1-a.html
Sorry, but no, I will not sell PCBs because it's difficult to send by mail from Brazil to Europe or USA. This is a difficult process ... but I will post the gaber files here. So, who wishes to do his own pcb, go ahead .. or if someone wants to create a new group buy I can send the eagle files to him (her)...
Well, I'm only a hobbyist DIY. I only measured volts and currents. I don't have a oscilloscope, but I'm looking to buy one. I had one but it is broken and so old ... I need a new one. So sorry, I don't know the answer. But may be some experts could help us ...
Hi, I do not know if this PCB serve to you. When I was working on the layout I did not bother to keep the original distance between the tubes. So if you will only use the OPT, PT and components, you can use this board. If you want to use your chassis, some changes need to be made.
Geber Files
When I started the project, the intention was to just make a handmade board. However, the end result pleased me a lot and for this reason I decided to start a new project. The board is working normally, but I believe that some revisions may be made. For example, delete the silk component values to get a board with clearer vision. If someone here wants to improve this layout, send me a PM. Follows the file geber in zip format.
When I started the project, the intention was to just make a handmade board. However, the end result pleased me a lot and for this reason I decided to start a new project. The board is working normally, but I believe that some revisions may be made. For example, delete the silk component values to get a board with clearer vision. If someone here wants to improve this layout, send me a PM. Follows the file geber in zip format.
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Hello All,
Along with your PCB version described in this topic, here's my turret board Michaelson Austin TVA-1 "Custom", just for the fun in aparté...
I was donated (yes, donated) some dead/dying tube amplifiers, and in the bunch there was a TVA-1 which was prevoiusly killed by an "obscure audio guru" so far that the havoc wasn't even repairable safely and sanely... Fortunately, the chassis and the transformer were genuine and intact.
I designed a circuit and built it inside. it is based on a DC coupled phase shifter and driver, inspired from an oscilloscope circuit. 5Hz-25KHz @-3dB / 70W rms / 0.8%THD / No NFB loop, thanks to the remarkable quality of the output transformers.
But yes, this is no more the original circuit of the MA TVA-1, that's right... Even if the external look is nearly original.
A+!
Along with your PCB version described in this topic, here's my turret board Michaelson Austin TVA-1 "Custom", just for the fun in aparté...
I was donated (yes, donated) some dead/dying tube amplifiers, and in the bunch there was a TVA-1 which was prevoiusly killed by an "obscure audio guru" so far that the havoc wasn't even repairable safely and sanely... Fortunately, the chassis and the transformer were genuine and intact.
I designed a circuit and built it inside. it is based on a DC coupled phase shifter and driver, inspired from an oscilloscope circuit. 5Hz-25KHz @-3dB / 70W rms / 0.8%THD / No NFB loop, thanks to the remarkable quality of the output transformers.
But yes, this is no more the original circuit of the MA TVA-1, that's right... Even if the external look is nearly original.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
A+!
What a lucky guy ...
Beautiful work. I wonder how long it took you to complete the assembly. This is exactly what I want to do on my philips tube amps that are in this link:
http://www.diyaudio.com/forums/tubes-valves/239902-need-help-monoblock-power-amplifier-el-34-a.html
As you said, if it is not working, let´s start to work ... Time is the problem!
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