Slenderchap

Christmas offering.... Fairchild Valve EQ ..... ez627
« on: December 23, 2016, 09:03:43 AM »
After 6 years of waiting I finally got round to finishing this project off:




It's a mono EQ made by Fairchild in the 1950's for mastering:
http://www.worthpoint.com/worthopedia/vintage-unobtanium-fairchild-627-tube-135319292

Colin
www.audiomaintenance.com


ruffrecords

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #1 on: December 23, 2016, 09:14:14 AM »
A thing of beauty Colin. I love the triple gang pots for the frequency selection and the good sized screened box for the PSU.

Happy Christmas

Ian

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #2 on: December 25, 2016, 04:17:47 PM »
great work Colin!

ubxf


ruffrecords

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #4 on: December 26, 2016, 04:05:20 AM »
http://www.preservationsound.com/?p=8602

THat is an incredible circuit for the era. I still have not got my head around it. The only 'obvious' part is the low roll at the input. Looks like the CF after the first stages feeds a twin T followed by and active twin T which then feeds back to the input. even the high roll is very different.

Thanks for posting.

Cheers

Ian

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #5 on: January 01, 2017, 12:02:45 PM »
12 u for stereo 2band eq?  ;D

Are the "roll" functions high/lowpassfilters?

Majestic12

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #6 on: January 01, 2017, 12:12:14 PM »
Did the magic eye tube in this EQ have any practical functions back in the day, or was it only decorative like in the Shadow Hills mastering compressor ?
« Last Edit: January 02, 2017, 03:48:24 AM by Majestic12 »

thomasdf

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #7 on: January 03, 2017, 06:37:38 AM »
Holy f***!!!!!!!! Amazing build!!!
How does it sound?

moltenwok

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #8 on: January 03, 2017, 01:34:49 PM »
Are you planning a group  diy offering ...... Please nicely

MrBlomski

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #9 on: January 04, 2017, 07:25:59 AM »
Hear Hear!!!!!!

Nice one. I've seen it on you're website when I was browsing and thought to myself "Hey, that is a new shiny object!"

:)

Best wishes for 2017!



tommypiper

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #10 on: January 07, 2017, 02:44:47 PM »
Very interesting. 

Colin, BTW your build document link on your site links to another project.
Imagine a wet, slightly chilled from its gas release and decompression, with water droplets condensing, sucking surface tension, slowly sliding down the side, capped by a healthy virgin froth on top..

BluegrassDan

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #11 on: January 10, 2017, 11:08:38 AM »
Colin,

Do you have any demonstration videos in the works? I'm very interested, but would like to hear it in action.

Dan

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #12 on: March 12, 2017, 11:14:25 AM »
Anybody have the potentiometer values?  I'd really like to try to build one of these from the ground up.

justinheronmusic

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #13 on: April 01, 2017, 10:56:32 AM »
Absolutely gorgeous work, man. Some of the best I've seen!
Justin Heron
Artist / Recording Engineer
www.justinheron.com
www.instagram.com/justin.heron

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #14 on: April 17, 2017, 04:31:21 AM »
Hey Colin,

what a gorgeous Kit, looks absolutely astonishing!

I ordered one right away and if the unit sounds as good as the schematic looks, i will make sure to get a second one.

However, having build a lot of stuff over the years, I wonder if there might be an alternative to using the Carnhill iron. They are excellent transformers of course, but I have made big improvements in some of my units by swapping new small irons against old clunky stuff.

Do you have experimented with some other irons? Anything you can recommend - Western Electric, UTC e.a. ?

Thanks and really great work you did here! Incredible nice and clean layout and PSU.

Happy Easter!

Re: Christmas offering.... Fairchild Valve EQ ..... ez627
« Reply #15 on: April 22, 2017, 12:09:55 PM »
I´ve built this unit in one very pleasant evening and have to say, this is by far the best kit I have ever seen. Also, it was one of the best and most satisfying evenings I´ve ever had cause it culminated in adding a very nice unit to my studio.
 
Everything is hasslefree, superbly organized and very thought through designed.

It holds ups to the highest standards.

Also, it sounds incredible. I spent a lot on nice tubes. Might be experimenting with different Input and Output Irons though, there is plenty of space left in the case, even though it will mess up the neat inner parts.