Feeler: Classic Solo

[Deepdark]

I guess the overall circuit will fit Inside a 2U rack, right?

 

[bernbrue]

I guess the overall circuit will fit Inside a 2U rack, right?

Yes

 

[ruffrecords]

I have decided to order 10 custom mains toroids. I can use two myself and I have commitments for 3 more. If you want one let me know. Cost is £22 plus shipping and Paypal fees.

Cheers

Ian

 

[Deepdark]

I have decided to order 10 custom mains toroids. I can use two myself and I have commitments for 3 more. If you want one let me know. Cost is £22 plus shipping and Paypal fees.

Cheers

Ian

one here please. thanks

 

[ding]

If it will power 2 boards I'm in for one too. Is it 12, 50, 240v?

 

[ruffrecords]

If it will power 2 boards I'm in for one too. Is it 12, 50, 240v?

Unfortunately it will only power one board. It is 6.3, 50, 240V.

Cheers

ian

 

[ding]

If it will power 2 boards I'm in for one too. Is it 12, 50, 240v?

Unfortunately it will only power one board. It is 6.3, 50, 240V.

Cheers

ian

 

[ding]

What can be used to insulate the 2 33k 2w at the joint? I've never done this so I'm not sure what to use. Will some kind of silicon compound that you get at the hardware store work?

 

[Deepdark]

If it will power 2 boards I'm in for one too. Is it 12, 50, 240v?

Unfortunately it will only power one board. It is 6.3, 50, 240V.

Cheers

Oh, i thought it could drive 2 boards. Take me out, i really need something to drive 2 boards

ian

 

[ding]

Dan at collective cases has this

http://collectivecases.com/?product=psu-transformer-szl-54

I think 250v at 200ma should power 2. It's not clear what's the va. It's kind of expensive at $68. It would be cheaper to get 2 transformers from antek at $28 + $11 but I imagine 2 transformers might mean more hum. Maybe???

 

[Deepdark]

trouble is that it cost me about 60$ of shiiping from Collective case looool. I think I'll go with an Antek and a little one for the phantom power, or, a Big EI installed outside de case and a little one for the phantom power, as I did when I build 2 REDD47. Never add trouble. We can always put a steel box to cover the transformer

 

[ruffrecords]

I have just updated the build information to include the Mouser and Farnell part numbers for the DPDT switches used on the four toggle board. It is in the ClassicSolo folder under the diy tab at my web site:

http://www.customtubeconsoles.com/diy

Cheers

Ian

 

[ding]

Ian,

I ended up going with the ones deepdark recommended because I liked that the bat length was a little bit longer and worked out better for me esthetically. Here is the mouser link.

http://www.mouser.com/Search/ProductDetail.aspx?R=200MDP1T1B1M2QEHvirtualkey61200000virtualkey612-200-F1121

What kind of insulating material do you use in the union of those 2 resistors?

 

[ruffrecords]

Ian,

I ended up going with the ones deepdark recommended because I liked that the bat length was a little bit longer and worked out better for me esthetically. Here is the mouser link.

http://www.mouser.com/Search/ProductDetail.aspx?R=200MDP1T1B1M2QEHvirtualkey61200000virtualkey612-200-F1121

What kind of insulating material do you use in the union of those 2 resistors?

Always good to have a switch choice. I will add that one to the build document. [DONE!]

I have a load of pre-cut insulating sleeves of various diameters. I usually just push one of those on or you could use a short length of heat shrink tubing for a guaranteed grip.

Cheers

Ian

 

[ding]

Just wanting to triple check that this transformer will power 2 boards before I hit that order button.

http://www.antekinc.com/as-05t240-50va-240v-transformer/

I'm going to go with this one for phantom.

http://www.antekinc.com/an-0124-10va-24v-transformer/

That's $38 plus shipping so not bad for both.

I think I might save my big 100va 250-250v one for your lunchbox project in the future. I got a little nervous about hum with something that huge in this particular build but maybe I'm just worried about nothing.

 

[ruffrecords]

@ding they look good to me. Have we discussed the best way to power two boards from one transformer?

Cheers

Ian

 

[ding]

On page 3 towards the bottom. Since this toroid has 2-6.3v windings I'm going to use one for each board and not worry about heater elevation modification for the second board. Unless you think using 12.6v for the heater is a better option. The 240v I'll connect in parallel between each board. I'll build out all the components on each board except for phantom which I'll share from one board to both daughter switch boards. I'll ground each board individually to chassis. Let me know if that sounds ok. When I get some time I'll put something together in Photoshop.

Thanks

 

[ding]

front panel idea. still wondering if I should do a 6 or 12 step input attenuator instead of a dual pot but I got the pot for now so thats what I'll stick with for the moment.

 

[ruffrecords]

front panel idea. still wondering if I should do a 6 or 12 step input attenuator instead of a dual pot but I got the pot for now so thats what I'll stick with for the moment.

I would be tempted to move the four toggles closer to the mic input XLR.

Cheers

Ian

 

[ruffrecords]

On page 3 towards the bottom. Since this toroid has 2-6.3v windings I'm going to use one for each board and not worry about heater elevation modification for the second board. Unless you think using 12.6v for the heater is a better option. The 240v I'll connect in parallel between each board. I'll build out all the components on each board except for phantom which I'll share from one board to both daughter switch boards. I'll ground each board individually to chassis. Let me know if that sounds ok. When I get some time I'll put something together in Photoshop.

Thanks

Good job you said all that because what I said was:

"Heaters are easy. They are AC so just parallel up the connection from the mains transformer. The phantom power supply should easily supply a couple of inputs so just build one of them and wire it to both mic inputs. The problem is the HT because it also creates the heater elevation voltage. The HT supply is designed to run one channel alone, so as well as using lower value smoothing caps I removed one stage of smoothing, to save both space and money. Ideally you want one HT supply to power two boards. To do this just reduce the value of R21 and R22 to 470 ohms. Connect the HT from the junction of R22/R23 on one board to the same point on the other. Link the AGNDs of the two boards together and connect the AGND of the board with the power supply to the chassis bolt. "

What this means is you only build one of the HT supplies - you cannot build both and connect the same 240VAC to both. But you also need to change the values of R21 and R22. so it can power two boards. This may cause a slight increase in ripple. To reduce that you could up the value of the 220uF smoothing caps to330uF. Something like Farnell part # 1973399 should be OK - just make sure it is 24mm diameter and 400V rated.

Both heaters need to be elevated - if you don't it can seriously shorten the life of the tubes - the 6922 is pretty tough and you might just get away with it but personally I would not risk it. One of those heater windings is plenty to run both boards so I recommend you daisy chain them. The other heater winding you could use for a power on indicator perhaps.

Looks like quite a few people are going to be doing this so I think I really do need to add a description and sketch to the docs.

Hope that helps.

Cheers

Ian