EMI RS124

[thakava]

I think my new projet wil be a Redd47 preamp and a RS124 compressor together in the same box and connected in series to create an unique old school channel.. using a GZ34 rectified PSU.

Well, then you should look into the Ultra British by Drip Electronics.
I happen to have a set of boards for sale
I don´t have the time to build it.

Best/
Tom

 

[anvl]

Thanks, thakava. I can't believe it !! It's the same idea .. Please send me PM with some pictures and price.
Anyway, I'm a big fan of building my own point to point design of the old school gear.
If a Drip PCB gives me all the job done .. it's not so charmy. Sorry !!!

 

[anvl]

Have you noticed differences between using 6BC8 tube and 6ES8 tube?

 

[Rob Flinn]

Have you noticed differences between using 6BC8 tube and 6ES8 tube?

My experiences were that the 6es8/ecc189 worked better than the 6bc8. I believe that EMI made this change too. In a nutshell you can compress a few dB more before the valve starts giving up.

 

[LincolnBL]

I own 3 Redd.47’s n an RS 124.I get such low prices n I would cock up recreating those myself.I envy you lads who do those epic recreations.I’ve asked my eldest brother,a brilliant engineer retired from Lockheed Martin,n he fails to answer my texts

 

[anvl]

RS124 tube varimu compressor on BASS DI (part1)

 

[anvl]

RS124 tube varimu compressor on BASS DI (part2)

 

[anvl]

Some test on BASS DI using my RS124 tube varimu compressor.
Input pot at 50%, output attenuator -5dB, Gain Reduction on meter about 6dB.
Remember I use vintage PSU (GZ34 rectifier + 2x0A2 regulator tubes).
I love this piece of gear !!!!

 

[LincolnBL]

Hi,
Anyone have any RS124 info? I think I've got it all figured out with correct information. I'd love to see a copy of John Hinson's removed RS124 web page, if anyone saved it. I'm trying to get an internal pic of a Hinson unit to check against, also...

Not sure how soon, but I'm going to build one, then post a build thread and schematics, layouts, etc... here. Then you guys can help me weed out any mistakes, or make some improvements to the design! Or if someone then wants to PCB it, I'm all for it.

NEVERMIND: My work here is no longer necessary. ;D

I have a Chandler EMI Abbey Road RS 124 and it’s my favourite compressor w I suppose Teletronix LA2A n TubeTech CL1B.All do something different n all sexy sound.And thanks to Wade Goeke for building a quiet perfect comp.Cheers

 

[rouni]

hi! I finished my 2nd rs-124 ptp. Works as it should! Except the classic strange thing happening with quick attack and release with an hot signal, the comp starts to lag(?) And of course even worst with the turbo mod i ve added (0.1 and 0.5 switchable caps before attack pot) . Today i ve tested an ecc189 instead of the 6bc8 without any modif and i can reach fastest compression without lag but the the compression has a totally différent mood/knee. Even with slower release i can hear more pumping effect than with the 6bc8. My question is: is there some modification to do before swapping tubes? (I suppose in the anode current?). Tomorrow i ll catch a 6bk7 also for testing.... anyone tried this? Also, last question, about the "lag" (don t know how to explain this but there is a point where the comp seems to panik at high speed), who solved this problem? Or maybe it s insolvable? The architecture of the machine make it limited at highest speeds? Thanks. Manu.

 

[lassoharp]

View attachment 116717hi! I finished my 2nd rs-124 ptp. Works as it should! Except the classic strange thing happening with quick attack and release with an hot signal, the comp starts to lag(?) And of course even worst with the turbo mod i ve added (0.1 and 0.5 switchable caps before attack pot) . Today i ve tested an ecc189 instead of the 6bc8 without any modif and i can reach fastest compression without lag but the the compression has a totally différent mood/knee. Even with slower release i can hear more pumping effect than with the 6bc8. My question is: is there some modification to do before swapping tubes? (I suppose in the anode current?). Tomorrow i ll catch a 6bk7 also for testing.... anyone tried this? Also, last question, about the "lag" (don t know how to explain this but there is a point where the comp seems to panik at high speed), who solved this problem? Or maybe it s insolvable? The architecture of the machine make it limited at highest speeds? Thanks. Manu.

You'd need a bigger side chain amplifier to get a faster attack (assuming your attack resistor is already at or near zero). Then you'd be approaching a Sta-Level. At higher speeds you have to keep the release slow enough relative to the attack to prevent unwanted distortion, but it may still have a pumping effect. You can get away with less difference between the two if you're just using it to catch transients of shorter duration. Program material requires the difference to be bigger (slower release times).

 

[rouni]

You'd need a bigger side chain amplifier to get a faster attack (assuming your attack resistor is already at or near zero). Then you'd be approaching a Sta-Level. At higher speeds you have to keep the release slow enough relative to the attack to prevent unwanted distortion, but it may still have a pumping effect. You can get away with less difference between the two if you're just using it to catch transients of shorter duration. Program material requires the difference to be bigger (slower release times).

Ok, that s the way i understood it also. You r right. Slowering the release time and the machine stops to "bug". AlsoToday i tested others ecc189 i found in my stuff, and i personaly prefer those to the 6bc8. I found one perfectly matched internaly (nos philipps yellow label) and the comp works better. Also i have 4 pos switch for the pairs of detector caps (47, 22 like the original, 10 and 4,7nf) , lowering those make also the the comp more stable at extreme settings, but of course depending of the material you want to process, each position maybe better or worse.... anyway i recommend this mod!

 

[Winston OBoogie]

I've now removed my posts re. Rs.124's. There's no need for my post with the scan of the original schematic, anyone who'd wanted it will have it by now so you'll be guchi.
I also felt the need to erase some posts I'd made as Jean Clochet (my way of helping guys build this thing, without any of the glory going to Winston, nor any pushbacks on me personally from EMI or Mossad for sharing magical mystery Beatle boxes while not having a real wizard's hat.

The scheme at the front that Rotheu posted was traced out wrong from a unit Id built of course. You guys know what the right bits are so...

Sorry about removing the Jean post with Mike Bachelor design notes file (Inc. All my stuff on the "sex" label unit, a couple of Mike Hedges originals, Len Page's list of all units at A.R. etc. but needs must now I'm moving out.

FYI, It looked like only a couple members saw it or downloaded it the 3, 4? weeks I had it popped up there anyway but, sorry it's gone. Ask around maybe... usually someone saves these things.
I'm out on this thread now.

 

[thomasdf]

If someone can send me or point me to the correct schematic Winston is referring to that would be awesome as I am planning to give the 124 a go in the coming year, and did not save the documents…
Thanks !

 

[Winston OBoogie]

If someone can send me or point me to the correct schematic Winston is referring to that would be awesome as I am planning to give the 124 a go in the coming year, and did save the documents…
Thanks !

Send me a PM and, when I have time I will send you the schematic. I simply wish to not have documents or photos that were part of a personal, at times very expensive, archive, up here in my name anymore.
That original RS124 schematic I posted cost me the friendship of Mr Lester Smith. Lester became my friend in the mid 1990's as a liason between myself and his old boss, the late Len Page. Mr. REDD himself. Lester trusted me. I wish to repent and take back some mementos, that's all, although the damage to the friendship is forever done and dusted I fear.

I posted the original schem because, someone else had reverse engineered one of my custom units. The schematic was wrong and would not have worked, yet my name was attached to it.
I felt it was time to come clean, it wasnt as if I'd found Dead Sea scrolls or anything. It was a modified Altec that had begun to take on mythical status. I knew the Chandler unit was on the way, based on 3 units still at A.R. Studios.
But I had documented about 10 or 11 original units that exist still in various places across the world, and had photocopies of original Len Page notes on 30+ original units from around the studio buildings and rooms at Abbey Road taken in 1966? (I forget exactly) and Mike Bachelor's design stuff where the various improvements and mods were implemented.
I felt it was an easy product to build if you just followed the last update of EMI studios "final official update" schematic. It gets you right where most of the stuff you hear on those records came from. No messing with stuff because, the chief designer Mike Bachelor (also for much of the REDD.47, as well as all that great TG gear) was a giant in this stuff. He was a personal hero of Rupert Neve so...

We need a curator for this thread (I must respectfully bow out of consideration) who can carry on for others like you who come along and want to have a go at building a unit.

 

[thomasdf]

Thanks a lot Winston, and I really mean it. So much knowledge around here ! Cant thank you and the community enough. I am sending you a PM.

 

[rouni]

Send me a PM and, when I have time I will send you the schematic. I simply wish to not have documents or photos that were part of a personal, at times very expensive, archive, up here in my name anymore.
That original RS124 schematic I posted cost me the friendship of Mr Lester Smith. Lester became my friend in the mid 1990's as a liason between myself and his old boss, the late Len Page. Mr. REDD himself. Lester trusted me. I wish to repent and take back some mementos, that's all, although the damage to the friendship is forever done and dusted I fear.

I posted the original schem because, someone else had reverse engineered one of my custom units. The schematic was wrong and would not have worked, yet my name was attached to it.
I felt it was time to come clean, it wasnt as if I'd found Dead Sea scrolls or anything. It was a modified Altec that had begun to take on mythical status. I knew the Chandler unit was on the way, based on 3 units still at A.R. Studios.
But I had documented about 10 or 11 original units that exist still in various places across the world, and had photocopies of original Len Page notes on 30+ original units from around the studio buildings and rooms at Abbey Road taken in 1966? (I forget exactly) and Mike Bachelor's design stuff where the various improvements and mods were implemented.
I felt it was an easy product to build if you just followed the last update of EMI studios "final official update" schematic. It gets you right where most of the stuff you hear on those records came from. No messing with stuff because, the chief designer Mike Bachelor (also for much of the REDD.47, as well as all that great TG gear) was a giant in this stuff. He was a personal hero of Rupert Neve so...

We need a curator for this thread (I must respectfully bow out of consideration) who can carry on for others like you who come along and want to have a go at building a unit.

Hi! Is the correct schematic "final official update" ,the one hand drawned dated 5/12/60 with the drawing number RS124/D1/2 ? THX!

 

[thomasdf]

Yes

 

[rouni]

Hi! just wanted to share pictures of my two last RS124 both point to point. Peace and thanks to all contributors of this usefull thread! Manu.

 

[inf0]

Hi! just wanted to share pictures of my two last RS124 both point to point. Peace and thanks to all contributors of this usefull thread! Manu.
View attachment 124826View attachment 124827View attachment 124828View attachment 124829

Hey manu! Looking amazing , congrats!

Do you happen to have any of the P2P schematics or info still available? I'm really thinking of building this and I would greatly appreciate it!