DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: mjc7900 on August 19, 2019, 11:21:15 AM

Title: Vintage MXR FLanger Volume Drop
Post by: mjc7900 on August 19, 2019, 11:21:15 AM
A few years ago I had Howard Davis modify my old MXR Flanger for 18v operation through a DC jack and he calibrated it at that time also.  Now that I've gotten back into live performance and put a board together I've noticed a volume drop of a few dB when the pedal is engaged.  Is there something simple like a resistor swap that I might be able to do to bump up the volume a bit?  Looking at the schematic I can't really determine which resistor would determine the volume of the circuit.
Title: Re: Vintage MXR FLanger Volume Drop
Post by: mjc7900 on August 27, 2019, 11:55:33 AM
Bump!
Title: Re: Vintage MXR FLanger Volume Drop
Post by: Scruffie on August 27, 2019, 12:07:38 PM
Equally reduce the value of the two mixing resistors going to the inverting input of the output op amp (150 & 82k on the schematic).
Title: Re: Vintage MXR FLanger Volume Drop
Post by: Govmnt_Lacky on August 27, 2019, 12:51:00 PM
Quote from: Scruffie on August 27, 2019, 12:07:38 PM
Equally reduce the value of the two mixing resistors going to the inverting input of the output op amp (150 & 82k on the schematic).

Maybe start with 120K & 68K. Work down from there.
Title: Re: Vintage MXR FLanger Volume Drop
Post by: mjc7900 on September 01, 2019, 10:48:51 AM
Thanks guys!  Those values were bang on for getting unity volume!