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Projects => Build Reports => Topic started by: PaulL on May 16, 2017, 05:04:17 PM

Title: Bolsterdrive Valve Boost Pedal
Post by: PaulL on May 16, 2017, 05:04:17 PM
Designed from scratch but built into a gutted Behringer VT999. Only the case, power switch and jack plugs remained.

Went for a bit of a gothic theme with this. The face is lacquered inkjet paper, the side lacquered wall paper - I obtained a sample from the local B&Q. Still perplexed as to who exactly would want black leather-look wall paper - different strokes I guess.

All thats left is to make the valve guards and and replace some components where I had to use multiples because I didn't have the values needed to hand. Took it into the friendly guitar shop and the guy thought it was great, so well chuffed.

(https://c1.staticflickr.com/5/4174/34658456816_fde064d141_c.jpg)

This is it coming to the end of the build and before decorating the case.

(https://c1.staticflickr.com/5/4173/33722179513_93f57e1a67_c.jpg)

Valves are 60/30L2 which are surprising good valves. Gives about 35dB of gain full out.
Title: Re: Bolsterdrive Valve Boost Pedal
Post by: jimilee on May 16, 2017, 05:41:17 PM
Daaaaaammmmnnn


Sent from my iPhone using Tapatalk
Title: Re: Bolsterdrive Valve Boost Pedal
Post by: Rockhorst on May 16, 2017, 06:20:22 PM
That's some electrolytic you've got there  :o
Title: Re: Bolsterdrive Valve Boost Pedal
Post by: PaulL on May 17, 2017, 04:54:39 PM
Made a couple of valve guards

(https://c1.staticflickr.com/5/4160/34678554316_d214145501_c.jpg)

Just got to work out how to attach them. Maybe some of those super-strong magnets??
Title: Re: Bolsterdrive Valve Boost Pedal
Post by: culturejam on May 17, 2017, 11:49:53 PM
All around pretty neato.

I gotta say, I've never seen that many resistors in parallel before. Kinda reminds me of bananas.  ;D
Title: Re: Bolsterdrive Valve Boost Pedal
Post by: Philthy on May 18, 2017, 12:44:06 AM
Grand on many levels. Kudos to you.
Title: Re: Bolsterdrive Valve Boost Pedal
Post by: PaulL on May 19, 2017, 10:16:23 AM
I've been playing with this for a while and it sounds great, but there is an issue that is the circuit will oscillate at full volume. Below is the tweaked circuit that should stop this.

(https://c1.staticflickr.com/5/4174/34710797306_dd8787b937_z.jpg)

BOM for circuit
(https://c1.staticflickr.com/5/4197/33908682174_92aa2b852f_b.jpg)

Rough schem of the power supply - Ignore the Tone control circuit at the bottom, this was a preliminary design. The Step Up is actually a 12VDC to 220AC step up inverter bought from Amazon. The output is actually a 220V Square wave. The huge capacitor in the photo above is 470U 400V but a 250V alternative should be a little smaller.
(https://c1.staticflickr.com/5/4185/33642617693_03dc60e785_b.jpg)

The next stage is to buy the resistors and capacitors to replace the ones that are made from multiple ones bunched together and neaten up the wiring in side.

These 6/30L2 valves are really great things.
Title: Re: Bolsterdrive Valve Boost Pedal
Post by: bluescage on May 22, 2017, 08:56:21 AM
Great job!!