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Pictures of your Tubelab amp

Thanks for the feedback mkane77g. I actually considered a layout like yours in the photo but for experimentation purposes since this was first ever electronics project I wanted to make it easier for testing out all the components. Having them all mounted to the top plate seemed like a better way to go if I needed to change components. I have the binding posts, RCA connectors and IEC behind the transformers and the four switches (if needed) and volume potentiometer in front to the left of the PCB.

The VTA ST-120 amp I have has the transformers in line since it's supposed to be reminicient of the Dynaco ST-70 amps.
 
My SSE chassis is 12 X 14 X 3 in size. I have my 3 Edcor USA transformers mounted along the 14 inch width. They are about 1/2 inch apart. The two output transformers are oriented so the bells are front to back. The power transformer is oriented left to right. The choke is mounted inside the enclosure mounted between two of the transformers. I'm hoping there won't be any hum issues. What are your thoughts?

Or is the layout mkane77g better?
The PS choke is by far the greater source of EM fields & should be mounted farthest away from virtually everything...think of it as a Leper...to be avoided.


-------------------------------------------------------------------------Rick..........
 
The PS choke is by far the greater source of EM fields & should be mounted farthest away from virtually everything...think of it as a Leper...

Well...that makes me need to redesign the layout slightly. I thought that if the choke is on the inside of the chassis while the transformers are on the outside...basically shielded with the 3.0 mm thick aluminum top plate...shielding would be adequate. But that's ok. It's still in the planning stages.

I'm also planning on using a motor run cap but that can be moved anywhere. My plan for the cap is to secure it with zip ties and adhesive backed zip tie mounts.

Of the two top plates I have I planned on sacrificing one to experiment with the layout. I drilled the tube socket holes with a step drill that doesn't exactly make holes with nice edges and I cut out the rectangular shaped hole for the IEC with a hack saw and a file. And there are a few extra holes because of the need to move the components to different locations.

Since you are saying the choke should be as far away as possible I can move it to the front left corner of the top plate and the switch and pot locations will have to change. But that's ok.

Once I've tested everything out the place I purchased my chassis from said they would CNC machine the top plate I have for a very reasonable price. And the original price for the chassis was also reasonable in my opinion. Not as cheap as the thin sheet metal and wood chassis you can buy on eBay, but also not as expensive as some of the chassis you can buy from the DIYAudio store.

I have access to 3D modeling software I know how to use and the chassis company said all they need is a DXF file of the top plate. If I had access to a mill I could program and machine it myself but at this time I'm without such equipment.

Thanks again for the advise.
 
pic
 

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Front Panel express is reasonable and fairly quick

The place I purchased my chassis from said they'd machine it for $30. The only I supply is the top plate. That includes their programming time, tools and machine time. I couldn't machine it for that little.

According to your picture, very clever, as I would have done, orient the core at 45 degrees.v..neither in-line with the B+ transformer nor the OPT's.

Good catch. The chokes in my VTA ST-120 are at an angle also. Thanx again.
 
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I'm sure your amp performs well but I'm trying to picture how what's outside of the box of the chassis is in relation to what's inside. To take that photo did you rotate the plate 180 degrees from how it would be positioned when assembled?

I talked to an electronics friend that said that it would be OK to mount the choke below the transformers since there is a 3mm aluminum plate between them. He did say I should rotate the choke so it's oriented 90 degrees from the power transformer. But if it's shielded by the aluminum plate why should it's orientation matter?

Oh well... I haven't sent the plate off to have it machined yet so I can revise the layout one more time.

Thankfully I modeled it in Solidworks.

Blake
 
SSE Amp Layout

I know I've been working on this forever. I bought a custom sized chassis from Landfall Systems a while ago and tried poking holes and windows in the top plate and though they are OK I am not really satisfied with how they turned out. The step drilled holes have chamfered edges that are uneven. I imagine if I had a drill press they would have turned out better but I don't. Anyway, Landfall said they use a CNC router to machine the holes and windows for a really reasonable cost to me so I decided to re organize the components taking everyone's advice into consideration. My plan is to have all of the components mounted to the top plate so assembly and disassembly will be easier than if I have components mounted to the sides.


I am planning to add all the bells and whistles and that is why I have three smaller switches in addition to the main power switch. I also have the choke mounted as far away from the transformers. And the motor run cap is also shown. My plan is to use adhesive backed zip tie mounts to attach it.


Anyway here are screenshots I just completed.
 

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Sprags,

Is placing the PT in the middle for aesthetic reasons? With this layout you will have the input wire going very close to the PT, and one of the speaker output crossing the PT too. I am not sure if these would actually cause any issues in real life - just observations. :)
 
The VTA ST-120 tube amp I have that is a Tubes4HiFi.com based kit based on the design of the original Dynaco ST-70 has the transformers oriented this way. On the ST-120 the RCS input jacks are in the front and the speaker output jacks are on the back. I figured if anything needs shielding I can do that with sleeves. However thanks for your input.
 
Two builds:

Tubelad TSE
- Shugang black treasure 300B-Z
- 65mA Bias
- B+ 368V, B- 275V
- Aux caps; clarity cap 70uF+85uF/600V
- Coleman DHT filament reg.
- Ale Moglia gyrator
- Choke Toroidy 9H/29R
- PT Toroidy Audio grade TS200VA 325-0-325@200mA, 6.3V(CT)@4A, 5V@3A
- 2x9V 2x37VA extra trafo (coleman supply)
- OPT Edcor CXSE25-8-5K (don audio GE)
- Auricap 0.22uF/600VDC XO Series
- chassis wood berk multiplex
- preamp DIYA/TB DCSTB/DCG3 Salas

Tubelab SSE
- 12AT7 NOS Mullard or 12BH7 EH (less, but enough gain)
- B+ ...V
- Triode mode
- Rk=330/6W+120/6W=550R
- Shugang black treasure KT88-Z
- Aux cap; clarity cap 70uF/600V
- PT Toroidy Audio grade 370-0-370@240mA, 3,15–0–3,15V@6A, 5V@4A
- 6.3V 75VA extra trafo
- OPT Edcor GXSE15-8-5K (don audio GE)
- Auricap 0.22uF/600VDC XO Series
- replaced the Rk/Ck from the 12AT7 with two Cree SIC diodes, felt it sounded better
- chassis wood berk multiplex
- preamp DIYA/TB DCSTB/DCG3 Salas

No real issues building these, but took some months to complete both chassis after having the amps running on a proto boards after a couple of evenings, except one...

Main issue I had was that I soldered the TSE DHT wires from the coleman reg to the upside of the PCB which caused some troubleshooting hours for I had a bad contact with the 300B tube sockets (causing strong oscillations). I should have taken the time to dismount the PCB and solder the heater wires underneath, will do that next time if I ever dismount it... replacing the current ones.

Happy with my build, both sound very nice, prefer the TSE slightly, but need some break-in on the tubes and my some more listing time.
After some break in I'll measure the FFT's with EMU0202&ARTA, see how they compare to the DIYA Pass VFET/M2 amps.

I'll consider changing the wood painted top plate to 6mm dark glass predrilled, if it is not too expensive, I left the amps run for a while to see if the thermal balance is ok, I may need more venting holes...

Thanks George for a great amp, I bought both boards on DIYA swap meet, next time (maybe a TSE 45 setup) I'll order the boards directly!
 

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