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OK, something to spice up GeekZone = here is where we post images of the INSIDE of audio equipment. Disclaimer; any photo...

Tim Farrant
replies: 1,174 views: 611,119
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phatbastard 21st December 2022
Avatar for MicroSonic

I have been collecting schematics for 30 years and 5 years ago I started make them available at my site but...

replies: 91 views: 147,607
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jokeramik 21st September 2022
Avatar for gabriel1

DSP Innovations has recently launched a FREE data sheet search site. The site, - Search Electronic Components ,...

replies: 19 views: 69,864
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msbettyhunt 27th March 2020
Avatar for AnalogQueen

I have an original Urei LA-4A, and the VU meter doesn't work when the unit is in gain reduction mode. The VU meter works in the...

replies: 1 views: 63
Avatar for AnalogQueen
AnalogQueen 1 hour ago
Avatar for komysh

hi. I have a rode nt1000. it have quiet flat response but I want to try it as modeling microphone with slate vms. I need owners...

replies: 0 views: 35
Avatar for komysh
komysh 8 hours ago
Avatar for disantlor

This may be a dumb question... but say you have a console with a line input preamp that is connected to an interface...

replies: 2 views: 118
Avatar for disantlor
disantlor 13 hours ago
Avatar for taitferge

Hi All, Firstly, I'm located in Honolulu Hawaii. That Being said there aren't many Tape Heads Left locally so I'm counting on...

replies: 4 views: 122
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taitferge 14 hours ago
Avatar for multimaxfm

Hello, everyone. Decided to repair my old friend, 528e voice proceccor (1996). Found something strange when started writing...

replies: 3 views: 58
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Johnny T 15 hours ago
Avatar for mikewellington

Hi, I posted this earlier on and was advised to ask...

replies: 2 views: 109
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Thomas W. Bethe 22 hours ago
Avatar for andrewpauly

Hi! I've been working on a Studiomaster Mixdown Classic 8. I opened it up to make sure the levels were selected properly (i.e....

replies: 0 views: 53
Avatar for andrewpauly
andrewpauly 1 day ago
Avatar for Johnny Digital

Any idea what are the specs (voltage, amps, etc) of the light inside the WA76 vu meter. They have been out of stock for a...

Johnny Digital
replies: 2 views: 149
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gyraf 1 day ago
Avatar for NReichman

Yes, I know they're old, but I have a JBL LSR4328P that was buzzing for a while, and now it won't completely power-up. I could...

replies: 2 views: 127
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NReichman 1 day ago
Avatar for WarmJetGuitar

Got myself a bag of 33uF 35v. Panasonic FR capacitors for the bias card on my Otari. But before I bother recapping the card I'd...

replies: 12 views: 454
Avatar for neil456
neil456 2 days ago
Avatar for trevor.sorrento

I want to connect the outputs of a Presonus NSB 16.8 stage box to the inputs of a Presonus HP60 headphone amp. The inputs I want...

replies: 3 views: 136
Avatar for trevor.sorrento
trevor.sorrento 2 days ago
Avatar for jsonic88

I know that it's best to plug all audio hardware into one single wall outlet to avoid ground loops, but if I have a wall outlet...

replies: 8 views: 215
Avatar for JohnRoberts
JohnRoberts 2 days ago
Avatar for QueenSisi

Very short question: do a new m7 membrane has a “break-in” time ? Like a speaker.

replies: 2 views: 133
Avatar for QueenSisi
QueenSisi 2 days ago
Avatar for owai

Hello, I'm trying to fix a Roland HP 2900g, but i can't find a schematic or a service manual. A small transistor...

replies: 19 views: 4,462
Avatar for Julka
Julka 2 days ago
Avatar for NaptownHepcats

Hey all, I have a rolland 301 that has been having some delay issues for a while now. For some reason the delay would just stop...

replies: 0 views: 52
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NaptownHepcats 3 days ago
Avatar for Rob2000

I had this crazy idea to flip the capsule of a big diaphragm condenser mic 90 degree so it will be siting perpendicularly to...

replies: 0 views: 69
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Rob2000 3 days ago
Avatar for gwayms

Hope this is the right area for this question. I have a Crate GT-80 Amp solid state/tube, I have put it in the shop but they...

replies: 14 views: 10,427
Avatar for lanavy
lanavy 3 days ago
Avatar for Trojanmantony

My console has been doing this for a while but basically from 150hz down, mostly in the sub bass region below 50hz I am getting...

replies: 1 views: 79
Avatar for Thomas W. Bethe
Thomas W. Bethe 3 days ago
Avatar for Drumbum_mer

Hi! Just curious if anybody knows if you can use the ghost tech piezos directly individually for each string and go perhaps...

replies: 0 views: 60
Avatar for Drumbum_mer
Drumbum_mer 4 days ago
Avatar for niva

Hi there! Been browsing this forum and I didn't find the info I am looking for. Got many SM57 and the alike which had all inner...

replies: 2 views: 100
Avatar for The Count
The Count 5 days ago
Avatar for Budda

I purchased a turntable that’s been a nightmare. Margules is the company and I don’t mind mentioning them to call them out on...

replies: 43 views: 835
Avatar for Budda
Budda 5 days ago
Avatar for che_guitarra

If you're handy with a soldering iron and a schematic, this is a thread to show off your DIY studio gear builds. Compressors,...

replies: 253 views: 80,198
Avatar for Thomas W. Bethe
Thomas W. Bethe 6 days ago
Avatar for Toyoto

Hi dear geeks, I wonder if I need LINEAR faders or VCA faders for my digital console? My name's Terence Meunier. I'm building...

replies: 1 views: 50
Avatar for Toyoto
Toyoto 6 days ago
Avatar for London Bridge St

Hello everyone, I am wondering if anyone here in the thread has had issues with their AWS 900 randomly rebooting? It seems to...

London Bridge St
replies: 5 views: 358
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orange 1 week ago
Avatar for RealCDugz

Hey everyone! My C800-G started making the ocean noise/white noise and based on the research I did, I will be replacing the...

replies: 13 views: 290
Avatar for audiospecific
audiospecific 1 week ago
Avatar for garronleslie

Hi all - I'm trying to locate a quality schematic for the ADA 8200 8ch ADAT interface. (plenty for the 8000) I'm looking to...

replies: 8 views: 378
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audiospecific 1 week ago
Avatar for ritelec

Hi all. For about a year now, as I add a picture to a post, I'm only able to add the attachment using GS add attachment...

replies: 8 views: 3,432
Avatar for Hobobonobo
Hobobonobo 1 week ago
Avatar for Paulwells66

Please see image below. Does this imply that the Preamp pin P is always directly connected whether the EQ is lifted or not? Or...

replies: 1 views: 94
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samwinston123 1 week ago
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Hello, I have spent weeks reverse engineering the Lexicon 300 GAL chip, finally I got it right. I am able to replicate the...

replies: 3 views: 169
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Mesmerised 1 week ago
Avatar for Etnier

My Masterlink CDR is no longer burning properly, and of course I have a project on hold because of this. I don't want to send the...

replies: 18 views: 5,261
Avatar for BHeerman
BHeerman 1 week ago
Avatar for HVI

Here are a bunch of KiCad design files for anyone who wants to use them. Some of the designs are tried and tested and some are...

replies: 0 views: 93
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HVI 1 week ago
Avatar for Fizmo100

Hi all, I've been installing my Alice ACM mixer over the last week following a few years where it's been sat idle with it's...

replies: 10 views: 3,269
Avatar for Matt Syson
Matt Syson 1 week ago
Avatar for Mlker

Hi my name is Joel and im currently about to finish my studies on SAE stockholm. Im writing a essay about consolltables, and in...

replies: 4 views: 1,298
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simonabright 1 week ago
Avatar for Seaclones

Hi everyone :) Based in the USA here. I bought a secondhand chameleon labs 7720 from Australia and it came with an Australian...

replies: 4 views: 191
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craigb 1 week ago
Avatar for focusbob

Hi! I own an Ibanez DMD2000 that works in all ways but modulation (i.e., the "M" in "DMD")... First, I...

replies: 2 views: 239
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focusbob 1 week ago
Avatar for Sonicblue99

So I recently got a Yamaha M406 and am planning on doing BXT403's mod Now, I thought I would put it out here before I do anything...

replies: 16 views: 14,327
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analoggg 1 week ago
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spring reverb IR production - did anybody try activating a metal sheet ads plate with something dirac-like impulse producing,...

replies: 0 views: 66
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DAH 1 week ago
Avatar for The Green Man

Hi all - I have question about electric load best practices. I have a furman ar-15 II voltage regulator (15 amp capacity). I'm...

The Green Man
replies: 3 views: 370
Avatar for UGP
UGP 1 week ago
Avatar for Rob2000

Hi guys! I would like to do a little mod to one of my microphone preamps and bypass all electrolytic caps in the audio path...

replies: 14 views: 530
Avatar for jaddie
jaddie 1 week ago
Avatar for Radardoug

So I've had a Summit TLA 100A on the bench for service. Apparently the bright spark who designed this was not that bright. There...

replies: 9 views: 1,648
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Kinho 1 week ago
Avatar for Tibbon

I bought a used 900 rack with nine 903 compressors in it. It appears in good condition and powers up with an LED showing on the...

replies: 1 views: 86
Avatar for Thomas W. Bethe
Thomas W. Bethe 1 week ago
Avatar for komysh

hi guys. I have a Neumann m147 kit. but when my tube will be blown (6s6b nos), I want to mod it to fet instead of lamp. why?...

replies: 2 views: 165
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Hymnographer 1 week ago
Avatar for David Kulka

I'm in the process of beefing up the UREI content on my website, and one often overlooked point that I will cover is termination....

David Kulka
replies: 95 views: 21,753
Avatar for emrr
emrr 1 week ago
Avatar for TormyVanCool

Dear all where can I find the schematics for the Focusrite ISA220, please?

replies: 10 views: 306
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TormyVanCool 1 week ago
Avatar for MLAudio

So I bought this preamp earlier this year (one of the first production pieces--payed $389 USD). I put it through its paces and...

replies: 88 views: 45,172
Avatar for EricCagle
EricCagle 2 weeks ago
Avatar for reprobyte

I was silly enough to store my Fostex PM1 in a hot space for a few years, and now I finally have a use for them I have found the...

replies: 2 views: 115
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reprobyte 2 weeks ago
Avatar for Grimace

Original post is below. But I just wanted to update this in case anybody finds this in a search or whatever. The problem is...

replies: 52 views: 5,135
Avatar for AuldLangSine
AuldLangSine 2 weeks ago
Avatar for Chagalj

There has been alot of talk about importance of conversion in recording chain, and lots of people want to know which AD/DA chip...

replies: 591 views: 433,845
Avatar for kirkounet
kirkounet 2 weeks ago
Avatar for VitaEtMusica

Does anyone know if the microphone-parts RK-12 (sold on for $159) and the Rayking RK12 (sold on Alibaba for...

replies: 26 views: 5,183
Avatar for Dohreetoh
Dohreetoh 2 weeks ago
Avatar for trubadoor

Hello, I'm very new to using a soldering iron, but I've soldered a few hundred cable connectors so far and put together a...

replies: 44 views: 5,784
Avatar for cdkelly
cdkelly 2 weeks ago