Monday, 23 February 2009

How to turn a poor reverb into a very useful reverb.


I've been working on this for a few days now. I purchased one of these: http://www.behringer.com/EN/Products/RV600.aspx, a Behringer RV600 Reverb Machine for a couple of quid. It's supposed to be a replica of the Line 6 Verbzilla pedal (more info on that one here: http://line6.com/tonecore/verbzilla.html) and it does a pretty good job of emulating it too. There are ton of very useful reverb tones to be had here. However, there was also 3 major problems with the stock unit:

1) The case was plastic and definitely not up to being trodden on for long!
2) The stock switching was useless. If you had trails on and the mix set below about 80% there was serious tone suck, if the mix was 100% wet and you turned the thing off it didn't pass your signal at all!
3) There was a noticable noise increase while using the pedal.

OK, so simple. A rehouse was in desperate need! I also decided to build up my own switching and mixing system around the pedal instead of trying to adapt the stock unit to perform how I wanted (It's all SMD so not ideal to take a soldering iron too!). 

The switching/mixing system I designed allows you to have trails on the switching but also to true bypass the unit. I added independent wet and dry level controls and a preGain control (I used a Zvex SHO as the preamp circuit) which controls the boost of the signal before it hits the front of the 'verb. The set up I produced, with the separate wet/dry level & preGain controls in combination with a few sneaky low pass filters, allows much lower noise operation than the stock single "mix" control present on the Behringer RV600. There is no distinct increase in noise between on and bypassed!

Below you can see what I eventually produced. Controls from left to right: PreGain, Wet Level, Dry Level, Tone, Decay, Delay, Mode.






Check out the neat custom Hammerite & Jackson Pollock paint job :-) On the left of the internal gutshot you can see my custom switching/mixing circuit. I'll be posting a schematic of my switching/mixing circuit soon so stay tuned if your going to be embarking upon any Behringer rehouses....

Next up the Behringer EM600 Echo Machine ;-)

P.S Thanks to SuperVelcroBoy for his heads up on things to look out for while rehousing Behringer stompboxes.

Thursday, 19 February 2009

Way Huge - Aqua Puss Analogue Delay

Woooooo. Thanks to FSB we once again have a fresh project over at freestompboxes.org. The Way Huge Aqua Puss has, for a very long time, been the holy grail for analogue delay freaks. Well Joe Gore was kind enough to donate his to the cause and took some great gutshots which allowed a schematic to be formed......

It seems there is nothing new inside. It's a standard Boss DM-2 clone with top quality parts! Still a great project to get involved in though. Check the thread out here: http://freestompboxes.org/viewtopic.php?f=7&t=4216

For a schematic, PCB and layout (Much thanks to Bajaman :-) check out his little project folder: http://freestompboxes.org/members/bajaman/Baja/Baja%20Wet%20Cat%20Analog%20Delay/

He calls his version the "Wet Cat" - build it, if you can find the ultra rare MN3005!


P.S On FSB right now there is a buy in of MN3005 chips so if you want one get down the freestompboxes forum and post up :-)