madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: thorpy6 on April 04, 2013, 10:45:05 AM

Title: Lavache Volume too low?
Post by: thorpy6 on April 04, 2013, 10:45:05 AM
ANyone know how i can increase the volume on my lavache build? its been built with a 2n5088 (all i had) and i find the volume to be barely above unity at 3 oclock on the volume pot. ive checked the pot values and all seems good, is it a designed in low volume or am i likely to have made an error. Despite this it does sound amazing!
Title: Re: Lavache Volume too low?
Post by: Thomas_H on April 04, 2013, 12:00:41 PM
The LAvache is not really boosting the signal very much. A lot of the amplification is eaten up by the clipping diodes. Depending on what you put there you only have 0.7V-1.4Vpp left. The rest ist clipped and therefore not there anymore. The original build was in front of an Amps preamp as far as i understand it. To get more you may want to put a boost after it.

Title: Re: Lavache Volume too low?
Post by: thorpy6 on April 04, 2013, 12:03:35 PM
bugger! hmm how to sort this? i might have to piggy back a SHO onto the back of this circuit.
Title: Re: Lavache Volume too low?
Post by: mgwhit on April 04, 2013, 01:52:11 PM
Thomas_H is right on the money.  The transistor just boosts the signal enough to clip, and there's no amplification after the diode clipping.  Even the "Boost" switch doesn't really give you extra volume---just extra distortion.  The LaVache/Electra is a cool "foundation tone", but I wouldn't try to kick it on for a solo.  If you want to boost it with a SHO (or something else), make sure you put your booster after the LaVache, otherwise you'll just clip more.
Title: Re: Lavache Volume too low?
Post by: midwayfair on April 04, 2013, 01:54:27 PM
You can use diodes with a higher clipping threshold. Try some silicon and LEDs or MOSFETs -- it'll still clip plenty when you turn on the boost, and who runs this pedal on less than full gain anyway? :)
Title: Re: Lavache Volume too low?
Post by: thorpy6 on April 04, 2013, 01:56:49 PM
so if i were to put a SHO after this pedal id take the out from the lavache volume pad---> into the IN on the SHO, then the OUT from the SHO into the footswitch?
Title: Re: Lavache Volume too low? (fixed with modification)
Post by: thorpy6 on April 05, 2013, 10:03:46 PM
So i fixed this, i put a modified SHO (1m resistors in place of the 10M ones to flatten the frequency response) i connected the volume pot pads (pad 3 to the sho in, pad two to the sho out and pad 1 to sho ground) into the SHO and removed the volume control on the lavache. the pedal now is at unity at ful lcounter-clockwise on the volume and boosts really nicely thereafter. actually a really sweet modification.

This pedal now sounds really sweet, especially as the correct transistor just showed up too and sounds so smooth in place of the 2n5088.

thanks for everyones help though!