In the spirit of sharing information this is a list of schematics and other technical information you can find on this site.

ROLAND RE-501 / SRE-555 ( all ~ 1M jpg files )
block
assy
input
main
psu

SSL 4000
82E20
82E10

Audix 35102 circuits ( these are all 2-3 Mb files! )
page 1
page 2
page 3
amp blocks
output mod
input mod

MCI JH-600 input channel circuits
mono input channel
standard eq
vari eq

Compressors
Neve
Urei LA-4
Urei 1176LN
Fairchild 670
early dbx160 style VCA
AWA G54639 Limiter - as modified
Quad Eight CL22 Compressor pg1 pg2 pg3 pinout
Quad Eight AM2B Opto Compressor
Federal AM-864 with mods
ADR F760X Compex - Block diag1 / Block diag2 / comp pcbA / comp pcbB / comp pcbC

Microphones
Neumann U67
Neumann UM57 and it's PSU UN57

EQs
Pultec MEQ 5 Eq only
Pultec EQP-1A

Jensen's document on connecting balanced and unbalanced equipment
Bal to Bal circuit of my own design for balanced to balanced with gain or attenuation