Optro 7500 console and compressors

by **The Tasmanian** » Fri Jun 05, 2009 11:52 pm

Any older techies have any idea where I can get a schematic for a Optro 7500 compressor?
Anyone got any going -?
I've got 12 of them - can't get them going......so frustrating!
The 7500 Console was ex channel 10.
I do believe the ABC and Channel 9 used Optro 7500 consoles in the 70's - maybe OB trucks?
Also a uni in Melbourne ? not sure about that one......
I think there were more Optro consoles in Melbourne than Sydney
I know that all the Optro schematics were thrown out at the tip many decades ago by Graham Thirkle in a rage.
Any help to restore these old Aussie gems would be much appreciated.
Chris Townend
BJB Studios

by **Chris H** » Sat Jun 06, 2009 11:01 am

You got 12 Optro comps! Wow. I have the channel strips from the 7500 desk that was in Melbourne Uni. It was a 12 ch desk with 8 bus out for 8 track recording. My tech has the shematics drawn out for these, and he might have them for the comp but last search he couldn't dig them up. I'm seeing him this weekend so will ask .

by **The Tasmanian** » Sat Jun 06, 2009 11:43 am

Hey Chris
this is good news ( I hope)
I have 16 channels / 12 Comps and 4 noise gates plus an 8 way mix bus.
I have heaps of spare meters if you need any - cause I scrapped my console as it was way too much real estate (2.7m long) for my home studio
I have some basic hand drawn schematics and pinout doc's that I could email you (but not for comp's).
Almost no-one knows about Optro's - they sound like vintage Neves - so fat and the EQ is really musical!
Maybe we could join forces and swap info?
Apart from racking the 12 Comps (Rob @ Proharmonic is trying to work them out with only frustration - not an opto design, similar to some old german comps)
I will be doing a 8 ch Optro console to sit beside my 8ch Electrodyne 711 console - and currently starting to building an 8 channel Valve Pultec console and finally a 8ch Quadeight Coranado.
A bastard mutant 32 ch console with passive mix bus - but Killa sounding!
Long live Optro!!!
It is up to us to keep them alive!

Chris Townend
BJB Studios

by **Chris H** » Sat Jun 06, 2009 2:23 pm

Yes, my desk in its original configuration was very big and the way the bussing was implemented with all the switching for monitoring added a bit too much noise. The pre amps are stellar sounding and i put 10 into a small console ,modded two of the mono mix busses to stereo.I racked two of the preamp strips for portability and they can patch into the console.
Here is a pic of it when i was putting it together before before everything was cleaned up.

by **Chris H** » Sat Jun 06, 2009 2:36 pm

Here is a close up of the racked pair of 7500's;

by **The Tasmanian** » Sat Jun 06, 2009 6:36 pm

Hey Chris
mine is a bit different
2 x aux's with 2 x pre and post toggles at the top of the module
My 4 top pots go: Aux1, Aux2, Pan, and MF KHz - but otherwise the same as yours - I would imagine that the pin outs and basic design are the same.
Although one of my mix busses is stereo
So my Optro may be a touch later - or a different factory order
Its a pity they look like a an old shit Jands console!!
How do you like the EQ - do you find it useable?
There is another 7500 in Melb - Simon Grounds owns it - he spent years refining it - changing caps - op amps etc and has sonically improved his quite a bit. And his is in really good nic!
I have no camera so I can't photograph my optro.
Let me know if you can find schematics or a tech who may be able to get the compressors going.
I have all Simon Grounds notes on how to improve the signal path if you want - he was very helpful - I spent an afternoon with his Optro last year.
I have 20 spare input transformers if you ever need parts.
Also maybe a few spare channels - as I only need 8 and a couple for parts/spares.
Regards
Chris

by **chris p** » Sat Jun 06, 2009 6:49 pm

Is it true that only people called Chris can post to this thread?

The Tasmanian wrote:Its a pity they look like a an old shit Jands console!!

C'mon, what's wrong with the old Jands consoles? Apart from their absence of headroom, thin EQ, and weird routing scheme. At least when you pushed one of those buttons, you knew it had been pushed.

Actually, here's a nod to the wise. When people talk about DIY consoles, Rick chimes in about how the metalwork will set you back over $1k. Not if you buy an old Jands console for $50 it won't. You can make up a nice little DIY channel that will slot right into that frame .....

by **The Tasmanian** » Sat Jun 06, 2009 6:52 pm

More Chris' please!!!!
Chris

by **chris p** » Sat Jun 06, 2009 6:54 pm

PS - anyone looking for some JANDS channel strips? Think vintage 1980's console, and having though about that, move on and get yourselves a bunch of these. 4 band gyrator EQ, solid state mic preamp, what's not to love?

by **Ausrock** » Sat Jun 06, 2009 6:55 pm

chris p wrote:Is it true that only people called Chris can post to this thread?

Sounds like a nasty rumour to me............ :-)

by **The Tasmanian** » Sat Jun 06, 2009 7:22 pm

Apart from the legendary vintage 80's Jands desk modules............Shhh word will get out!
Hey Chris
I don't seem to have the epoxy covered bits - I think these were the early "paranoid" models
I heard about the epoxy rumours.....Covering shit in epoxy so no-one would rip the design off!
Your Byers Rock - I run 2 x Rola 77 mkIIIs 1 x Rola 66 and a 1950's Byer with 110db of gain! - this was from the 1956 Olympics in Melb. All the Journalists at the Olympics were forced to use the Byer valve tape machines - I have an old photo of a stadium full of journo's sitting in front of these green valve mono tape machines in 1956 - as far as one can see!
We have so much great Aus audio history - I am glad to find another brother to keep them alive.
And the quality of all this stuff is amazing - AWA's still compete with the best compressors in the world!
Regards
Chris
Any more chris's want to pitch in on this love-in for great aussie lost gear?

by **Chris H** » Sun Jun 07, 2009 2:23 am

My Byers were refurbed and moded for me by a local by the name of Gerard McGough. He changed the signal path a bit and did a great job of making mine a lot quieter. I have a few inline pads that bring down the output a few dB....10 or 20 dB in fact so my other gear in the chain can handle the grunt....same with the AWA stuf that was made for the ABC +4....hell no , make it +8. Very talented individual he is who used to do some work with Sing Sing's gear. My mate Phil Butson had him working at Sing Sing for a while. Gerard loves the valve gear and had a special mod for the Ampex 350 tape pre's where he added a presence pot. His mod turned them into an awsome sounding box. He also built me a simple but very affective Bramar valve eq. I sold my Ampex 440 to him. I will never forget the time he played me a recording he did of a drum kit with a single U87 through one of his pre's to that old Ampex....HUGE!....... AWSOME!......HUMBLING! Like many talented people he is slightly on the excentric side of things in a lovely way.
.........and you gotta borrow a camera and post some pics of your optro gear.
I met Simon quite a few a few years ago when he was in Collingwood (where is he now) and bought the Ampex AG 440 off him. Funny thing , i walked into a small studio in Belgrave last year and there it was..... Gerard had sold the 440 to the guy running that studio. I now have an Ampex 1100 that uses the same cards. Simon's Optro console was a beast....... Huge.....and the reverb contraption he had from the Sydney Myer Music Bowl....i'm still trying to figure that thing out! Some sort of metal disc recorder with valve amps etc etc.
Should we be talking about all this stuff?...ah well i suppose the horse has already bolted!
More Beer...nah! More Gear!~

by **Chris H** » Sun Jun 07, 2009 2:36 am

Hows the comb over!!!

by **Chris H** » Sun Jun 07, 2009 2:56 am

To answer your question about the eq. I find the 7500 very useable but in a more modern way than the eq in these older optro modules that are passive and also have an opto comp/limiter. These came from the first console built for Bill Armstrong and are my favorite sounding all round. Compared to these the 7500 are harder sounding in an API style of sound...not in a negative way...shit how do you describe sound? For a firm punchy drum sound and edgy guitar, i would go the 7500 every time but for bass, vox, and a more bluesy guitar sound and an over all softer edge these are the go, especially if you are wanting to add the so called sonic airbag quality that helps give to digital recording what is missing compared to using tape. These just do it, and are very usefull in many mastering applications. What comes to mind are some of the sounds on Cold Play's parachutes recording to give you an idea. You can just keep adding level on the input and the limiter will do it's job without any pumping artifacts etc, and you can push it to reach the desired amount of sweet distortion if thats what you want. Of all the bits and peices i have got, these are the ones i could not live without.

by **13thbeach** » Sun Jun 07, 2009 3:47 am

Well sorry to ruin the great run of Chris's here, but another great vintage Australian company is the Zephyr microphone company from Melbourne. I have a few of the huge ribbons and they sound just great. Right up there with any classic RCA etc....

You can call me Chris if you like.

by **The Tasmanian** » Sun Jun 07, 2009 10:03 am

Hi Matt (honorary Chris) - how are you?
never heard of the Zephyr - apart from those old English Cars...

Chris, did Graham Thirkle and co design all this stuff? I know at the time nearly everyone was ripping each others designs off...
(not AWA - they seem to licence bits of their designs RCA & Telefunkin - very forward thinking - or they had good patent lawyers)
These designers made shit to last - My 2 Rola77 MkIII's were used continuosly in film post in Sydney for nearly 40 years - right up until late 90's - and although I have removed the tape section and put away in storage, the heads and mechanics I reckon would last another 100 years of daily use - amazing design -
A yobbo version of a Nagra - tough/ ready for a fight / no fancy little bits in it - bare knuckles on a dirt ring!

Rob from pro harmonic had to pad the Rolas, add +48v and take some tape recorder bits out of the pre's path - my dog they sound good!

Who can give me a rundown on Optro the company
Rola was an American company - I'm confused?
Byer - must have been pre Rola - correct?

Chris - I would love to check out/dribble over your Optro one day when I am on the road from Syd to Tas (far too often)
Hey I have an Ampex 440c 1/4 inch gathering dust in Sydney - Can the line in modules be modded as line drivers or mic pre'?

I think I am asking too many questions....
Its been F*#@^kin raining for a week down here - rivers everwhere !
Chris

by **The Tasmanian** » Sun Jun 07, 2009 10:07 am

Hey Chris
Are those older optro's Valve?

by **Linear** » Sun Jun 07, 2009 1:14 pm

Hi,

I don't have anything to say about Optro stuff (apart from the fact that I'm ver proud when aussie made stuff kicks arse).

But I thought I'd post something because my name is Chris...

Chris

by **The Tasmanian** » Sun Jun 07, 2009 2:21 pm

Hey Chris V - you get double respect - you drive an AWA console, AND your name is Chris.
Is yours the Opera House console?
I have 4 of the early Opera House models (so I've been told) - they sound awesome but the pots are a bit shit !
Was your the 2nd desk for the Opera House?
Chris

by **rick** » Sun Jun 07, 2009 2:41 pm

Byer and Rola were from the same family and definatly australian
There is a link to there history on the web I cannot find it today
For the train spotters the byer motel is on the Hume highway it's what.
Mr byer did when he retired I believe
There a free rola mic pre for the first guy to post up a picture of the motel sign
It features the same logo as the byer tape machines !
I have seen it many times but ... Well I notice all kinds of things ..

by **TimS** » Sun Jun 07, 2009 3:13 pm

rick wrote:Byer and Rola were from the same family and definatly australian
There is a link to there history on the web I cannot find it today
For the train spotters the byer motel is on the Hume highway it's what.
Mr byer did when he retired I believe
There a free rola mic pre for the first guy to post up a picture of the motel sign
It features the same logo as the byer tape machines !
I have seen it many times but ... Well I notice all kinds of things ..

Better be true to your word Rick

Tim..

by **Gian** » Sun Jun 07, 2009 4:07 pm

rick wrote:Byer and Rola were from the same family and definatly australian
There is a link to there history on the web I cannot find it today
For the train spotters the byer motel is on the Hume highway it's what.
Mr byer did when he retired I believe
There a free rola mic pre for the first guy to post up a picture of the motel sign
It features the same logo as the byer tape machines !
I have seen it many times but ... Well I notice all kinds of things ..

See what happens when I am soldering when I should be rendering my laundry...someone gives away a mic pre.

by **heathen** » Sun Jun 07, 2009 4:10 pm

What about a closeup?

Who disabled the smileys?

by **TimS** » Sun Jun 07, 2009 4:17 pm

heathen wrote:What about a closeup?

Who disabled the smileys?

Who asked for a close-up - it was just 'post up a pic of the motel sign' - there ain't no changing the goalposts!!!
Well, there are 2 signs in the 2 images - the one over the awning at the front of the motel and one over the MOTEL sign (in red)..

Smiley images have never worked - Mark disabled it long ago :-(

but it seems smiley typeset faces are disabled now too!! WTF?

by **ChrisW** » Sun Jun 07, 2009 4:47 pm

The Tasmanian wrote:Any more chris's want to pitch in on this love-in for great aussie lost gear?

No.
But feel free to continue while I watch on.

by **heathen** » Sun Jun 07, 2009 5:57 pm

TimS wrote:
heathen wrote:What about a closeup?

Who disabled the smileys?

Who asked for a close-up - it was just 'post up a pic of the motel sign' - there ain't no changing the goalposts!!!
Well, there are 2 signs in the 2 images - the one over the awning at the front of the motel and one over the MOTEL sign (in red)..

Smiley images have never worked - Mark disabled it long ago but it seems smiley typeset faces are disabled now too!! WTF?

Fair enough, heh. I wonder if Rick will be doing an easter egg hunt for easter, you know like hiding bits and pieces of old gear around Sydney and leaving clues on the forum? Could be fun.

by **13thbeach** » Sun Jun 07, 2009 6:08 pm

Wow! Tim,
That was amazing, to get those pics up so fast.

Chris...um....from tassie, If I get a chance I'll post some pics of my Zephyrs. They have to be seen/heard to be believed.

by **astrovic** » Sun Jun 07, 2009 6:11 pm

All I can add to this thread is my first name and my huge appreciation of the makers of this gear.

by **rick** » Sun Jun 07, 2009 7:18 pm

TimS wrote:
rick wrote:Better be true to your word Rick

Tim..

always am ...
jeez i imagined , that someone would have at least DRIVEN past it and noticed it to claim their prize
instead of googling the damn thing before i even got home for the day

better gimme... a week or so to dig one out
i never mentioned that it would be working right...? :)

by **TimS** » Sun Jun 07, 2009 7:31 pm

Took quite a bit to actually find it actually..
Working - it should be ready to plug and play!! But if not, send it to Rob..
You didnt specify where they should come from!!
Actually, I was there for a family reunion quite a few yrs ago when I was married the first time - I have driven past it before as well..
My ex-mtoher in law has family in Holbrook.. ;-) We could have even stayed there from memory..

Optro 7500 console and compressors

Optro 7500 console and compressors

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