Building a symmetrical PSU B1 buffer

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Progress report. Time to tweak DCB1.

Completed standalone lightspeed to put into this thing....
Blew up Salas baby-shunt 5v power supply.Need some new LEDs. (I know how I blew it up, incorrect hookup to Bench Power supply.)
Found 2 X 15ohm 5 watt mills for juicing up the current,
lost 4 220ohm PRPs i planned to swap in from Kiwame's.
So stalled again.
 
If you are increasing the current and implicitly the heat, then perhaps the Lightspeed's optocouplers might not be so happy living under the same hood?! The author of the design even puts those optocouplers in wax and keeps them thermally coupled together.

This is the reason why I'm thinking about making a nice small wooden case for the LS, physically connected on top of the DCB1 case and with wires going through the top of the DCB1 and the bottom of the LS case, respectively. Would look kinda strange, but the unusual look has already been settled when I decided to use some rubber pass-through collars to get my diy IC wires inside the DCB1 chassis and solder them directly to the board. There will be a couple of RCA in and out connectors too, though. The best place for those pass-through collars would be the top of the case, of course :). If I don't change my mind, the DCB1 case would open by removing one or perhaps both side walls, like a computer case.
 
Progress report. Time to tweak DCB1.

Completed standalone lightspeed to put into this thing....
Blew up Salas baby-shunt 5v power supply.Need some new LEDs. (I know how I blew it up, incorrect hookup to Bench Power supply.)
Found 2 X 15ohm 5 watt mills for juicing up the current,
lost 4 220ohm PRPs i planned to swap in from Kiwame's.
So stalled again.

How much did you spend on the light speed volume pot ? ( just curious )

Jase
 
Heat will effect the LDRs. I have them right on the inputs of my DCB1. No problem, but I dont have it biased up any higher than normal. Heat will change them, but then again they are all effected similarly so its really not a big deal. Though it will be interesting to find out what happens with TeaBags if he biases up high. I have never tried them right next to a heatsource.
I gave him the LDRs to play with so his cost is nothing.
I charge 38.42USD for a set of matched LDRs. This includes shipping worldwide, all paypal fees and a $3 donation to DIYaudio. I will be shipping towards the end of January. Just finished measureing 120 of them at 4 different points a few minutes ago. So maybe shipping earlier. We will see.
Uriah
 
Heat will effect the LDRs. I have them right on the inputs of my DCB1. No problem, but I dont have it biased up any higher than normal. Heat will change them, but then again they are all effected similarly so its really not a big deal. Though it will be interesting to find out what happens with TeaBags if he biases up high. I have never tried them right next to a heatsource.
I gave him the LDRs to play with so his cost is nothing.
I charge 38.42USD for a set of matched LDRs. This includes shipping worldwide, all paypal fees and a $3 donation to DIYaudio. I will be shipping towards the end of January. Just finished measureing 120 of them at 4 different points a few minutes ago. So maybe shipping earlier. We will see.
Uriah

not bad price, what is the total value of the whole thing built minus psu, so would 100$ be enough for parts ie board transistors matched ldr's etc etc ?

Jase
 
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My chassis currently has adequate ventilation. The IRF's are attached to the bottom of a steel chassis, so I will back off bias if they run above 50c, or go unstable on steel.
I plan on running lightspeed connected in line with existing volume pot wires of a mesmerize.
I wanted to try the LDR's, because I know what a lightspeed can do in a good system.
The clarity and back of neck hair raising value I heard makes it a want to tweak for me. Why not just do lightspeed? Well plenty of systems don't have low enough output sources to make that a best match. The DCB1 does.

A fully assembled lightspeed with a radio shack pot costs less than a lot of attenuators. Dont need a good one since it's not in the signal path.
 
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I am just going to steal the power off the main Power Cap (as salas recommended),
Run it into a separate 5v regulator, although I am not against building with another transformer. It may provide better isolation that way, although I am far from an authority on the technical aspects.
 
Yeah Jase, Thats more than enough. I think if you bought my LDRs and then all the parts you need you would be at maybe maybe $70 but thats including a nice little toroid. So it can be done rather inexpensively. And I love the sound with the DCB1. I have to try biasing that thing up when I get some sinks on it.
Uriah

Yeah i have to track down the pieces, id like to buy a nice potted / board mounted toroidal transformer for my psu, something clean power and nice for the B1 & the light speed.

J'
 
Yeah i have to track down the pieces, id like to buy a nice potted / board mounted toroidal transformer for my psu, something clean power and nice for the B1 & the light speed.

J'
A few weeks ago in this very thread I've been recommended this Hammond at Mouser, if you are OK with it not being toroidal and with the 2 weeks waiting time. I have followed the advice, btw.
 
Can I get a suggestion for some hookup wire? Guage/ Type / Length - I'm putting together 2x Hypnotize & 2x Mesmerize.

Just another quick question. If I do not want to hookup all 6 outputs on the Mesmerize - should I just get a 3 position rotary switch and just connect three outputs from the switch to the connectors on the board? (I've already have six relays stuffed on board.)

Thanks,
JG