Re: Hayes Middlesex Pre/Channel
« Reply #60 on: March 04, 2019, 04:50:18 AM »
thank you for your reply it make sense, and yes you've not seen something like this because this time i feel creative and i've tried to be very very cheap, a line/mic switch will work for sure. but can't we shunt the primaries of the trafo with a resistor to change its ratio behaviour? or am i going too hippy thinking?  :D


ruffrecords

Re: Hayes Middlesex Pre/Channel
« Reply #61 on: March 04, 2019, 09:10:21 AM »
thank you for your reply it make sense, and yes you've not seen something like this because this time i feel creative and i've tried to be very very cheap, a line/mic switch will work for sure. but can't we shunt the primaries of the trafo with a resistor to change its ratio behaviour? or am i going too hippy thinking?  :D

The 'normal 'way to combine a mic and line input is to do it on the primary side of the transformer. So add a 1K2 resistor across the primary winding. Add a series 10K resistor from each side of the primary winding to the hot and cold inputs of your line input. The mic input is connected right across the 1K2.

Cheers

Ian
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'

Re: Hayes Middlesex Pre/Channel
« Reply #62 on: March 04, 2019, 10:57:19 AM »
thank you, i'm going to use this solution for sure. i was thinking that a transformer could isolate the two different input from each other. i will never understand transformers!

waltzingbear

Re: Hayes Middlesex Pre/Channel
« Reply #63 on: July 26, 2019, 01:39:17 PM »
Those schematics here are lovely and give a good insight into the design of this classic console. But we don't have the schematics for Amp B or C, which combined describe the summing characteristics of this desk, which in my experience is unique.

Anyone have them to publish here? Most of it can be derived from the description in the pdf Mk II manual, but it would be nice to have the schematics in full.

Cheers
Alan