Obsessed with the Quad Eight 312/310/MM403 sound - any ideas?

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The QE Rack is finally finished! Thanks Rob at WorldProAudio!

Came here specifically to second that shout to Rob Harvey at WorldProAudio. I've spent many an hour working through relays on a Scully 280 with Rob, he's a far better tech than you need and a really sweet guy.
 
Came here specifically to second that shout to Rob Harvey at WorldProAudio. I've spent many an hour working through relays on a Scully 280 with Rob, he's a far better tech than you need and a really sweet guy.
Agree with you 100%. Rob is a real great guy. The real question is.....what will we do when people like him retire? do you see the new generation caring for the old gear? I don't....try finding an electrician or plumber, let alone...old gear magician!
 
I've been reading along for the last few days and want to join the party if that's OK.
Here are my QE MM312s that Ken restored for me some years ago.
I've sold my Neves and my Calrecs when times were tough.
I'll hopefully never have to sell these. They are stellar.
Those are real nice. I hope you sold the others because these are better!.
 
Agree with you 100%. Rob is a real great guy. The real question is.....what will we do when people like him retire? do you see the new generation caring for the old gear? I don't....try finding an electrician or plumber, let alone...old gear magician!

Goooood question. I think pro audio techs (and trades in general) are definitely a dying breed, but there’s definitely a younger contingent picking up the slack a bit. I know a handful of 30-somethings that are willing to dive in to some antiquated shock hazards…what I fear most is the knowledge loss. A lot of these guys have a head full of invaluable information….like you can plug 6-8 57’s into patchbay mults and run them all into one transformer-isolated preamp for everyone’s talkback. With the transformers isolating everything the signals sum just fine at basically equal level, you get to use one pre/channel/send.

There are some among us who’ve done informal apprenticeship with these guys to help carry the torch so to speak. Ken Hirsch taught me how to wire loom like it was 1967, Rob Harvey taught me how to calibrate, modify and menacingly stare at the 16trk Scully 280 so it would behave itself.
 
Its great to see so many people still loving their QEE gear and even more seeking it out to add to their desert island collection.
Its been a long-wild ride since that ridiculously crowded garage in Simi Valley a few years ago. The new factory building is appropriately spacious for the wide-open plains of Arizona,... and the clear skies and sunsets never get boring. The only mistake I made was not making the building even larger, since it has been flooded with work ever since Covid and there appears to be no end in sight.

RE: the massive tech shortage....
Yes its astounding that so few people have found their way into electronic repair of vintage gear. Literally ever decent tech I know has been overwhelmed with work to the point where most of them are so busy they cannot perform field service anymore. Even my service trips to LA have to be planned weeks in advance so I can get to everyone in a few days.
That said, I have been building a relationship with the founders of CRAS (Conservatory of Recording Arts and Sciences) to bring on any student show has an interest in technical knowhow. Hopefully I can help ease the burden by giving them the basics of gear maintenance and repair as these kids graduate and head out into the real world of music, (where not everyone becomes a platimum selling producer/engineer!!!).

QEE EQ frequency levers:
We have them in stock, currently in silver/zinc finish and at prices far below those outrageous ebay/reverb listings.
Chemical processing for a black oxide finish is certainly possible, but it would have to be on fairly large quantity order to make it worth the batch processing cost.

The topology of the late 60's through 70's inductor eqs from QEE, Electrodyne and API are built on the same conventional Active-Reciprocal circuitry, not on passive technology like early 60's offerings from Altec, Pultec, Cinema Engineering, Electrodyne, Langevin and many EU brands... (all based on ancient Bell Labs patents), or Feedback loop equalization like early Helios Black & Silver faced channels, Universal Audio, Spectrasonics and most of those above (just to name a few).
The sound of an active LCR eq is really quite unique and the complex harmonic responses generated by interactions in their multiple LCR networks is almost impossible to imitate, even in the best of plugins.

I agree that our Electrodyne 511 & 2511 (the eq section from our vintage 711L channel) is quite different from our QEE 300/400 3-band series eqs in that the frequency centers are not all the same, but primarily the Q (bandwidth) of the peaking frequencies is much gentler since, like our QEE MM-61/71 eq, this design is optimized for ideal two band equalization where critical mic selection and placement captured the desired sound, and "tone shaping" was all that was required for the perfect capture to tape or during mixdown. Many of these late 60's/Early 70's two band eq based consoles had one or two pairs of more comprehensive eq built-in that could be patched anywhere for tracks requiring a bit more tweaking.
That said, I have heard some pretty aggressive eq, very artfully done with 511,s or the dual channel 2511, and the differences in overall sound between our Electrodyne and Quad-Eight products is significant enough, that having both is never a bad thing.

Our 300 and 400 series Mixer Modules and EQ,s have dozens of variations (different eq points, Hi/Low filters, Led Peak indicator, Mic pre or not, Channel Phase switch, Onboard Echo/Cue sends), but the basic MM-310b and EQ-312a seem to be the most well known.

Pricing for vintage QEE gear and so many others, has continued to spiral out of control (IMHO), even though we continue to stock parts to make these legendary three band eqs and a range of preamps for anyone who asks. We even have a new custom QEE console with 3band inductor eq,s scheduled to ship to a lucky owner at the end of the year.

A 500 DIY version is certainly doable if you can locate custom wound inductors in the right core size and special ferrite material, squeeze them onto the cramped 500 card space with QEE input and output transformers and find custom concentric switches
The opamp will have to be re-biased to run on the low +/-16v provided by any 500 rack (excepting 51x types) and headroom will suffer greatly from the typical +29.7dbm the AM-4 is capable of at +/-28v. Inductors alone are a fairly steep hill to climb as these eq,s require four separate multi-tap inductors to cover all the frequencies.
Different opamps, smaller inductors, no bridging input transformer and operating at depressed levels internally could be used to manage the tiny 500 card space and severe drop in supply voltage, but then it would not sound anything like the original.

Preamps:
There are at least four distinct QE preamp types primarly depending on year of original design, with many variations on each over the years (not including late 80's IC based Westar and related Music, Film and Broadcast designs).
The main differences are:
-Mic Input transformer type.
-Opamp type (AM-3/AM-4/AM-4b, AM-7, AM-10/AM-12/AM-12b)
-Gain control topology (incoming level attenuation type, primary impedance selection, opamp gain control and number of gain steps).
-Output transformer used or direct opamp output.

QEE Consoles that marked the most recognized preamps and eq,s were:
-QEE 1682 and 2082 and dozens of custom consoles using MM-61 and MM-71 Channels:
Village Recorders, Shangri-La Ranch Malibu, Wally Heider SF, Record Plant, Quadriphonic Sound Nashville, Neil Young, Smokey Robinson, Jack Clement, Creative Workshop, Sunwest Recording, Leon Russell, Sound Factory West and dozens of others.

-QEE Custom Music and Film Scoring consoles using MM-310b, MM-403, MM-312s, and dozens of custom variations:
Motown-West (Hitsville West)/Signet Sound, CBS Studios, Advision London, Ardent Studios Memphis, MGM Pictures, Bearsville Records, A&M Records, Warner Brothers Records, Beach Boys, Capitol Records Hollywood & NY, ABC Australia, Warner/Pioneer Tokyo, United Sound Recorders and many more.

-QEE Coronado, Ventura and Pacifica (Stock Console Series):
Garth Brooks, NBC studios Burbank, Vangelis (Chariots of Fire soundtrack), and far too many major hits of the mid 70's to late 80's to count, with hundreds of installs worldwide, standing head-to-head with similar consoles from API, MCI, Harrison and other hybrid designs.


As was true from the companies inception in 1962 (as Quad-Eight Sound) to today, we will build any design console or outboard gear based on the customers desires, with inductor eq based consoles having been ordered and built well into the mid 80's, long after Gyrator eqs were the industry standard.



Ken Hirsch / Director of Engineering
Orphan Audio www.orphanaudio.com
Quad-Eight Electronics www.quadeightelectronics.com
Electrodyne Audio www.electrodyneaudio.com (a division of Orphan Audio)

"Education is the cure for everything"
 
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I'd also love to own one, a single racked unit... for the final bass cut/sculpting of the Cylon voice, just how they did it in 1978. It takes a few trips through 511, 712, and the 312 EQ's to get it just right. It's the final missing piece in my studio!
 
Thanks for the great post. I have two MM-403 in need of service. Do you have the schematics? I can't find them anywhere.
Tomas,

Sorry, I don't get much time away from my bench to visit the forums. (Thanks for the support boji, you know how deep the customer work shelves are stacked here).

Everyone should know the quickest way to contact us is via one of our many website email pages (a few listed below) for parts, docs, tech support or custom builds.

MM-403:
A custom channel built for five consoles at ABC (Australian Broadcast Company), basically an MM-405 film eq module plus full mic preamp and integral fader.
We have those docs in the original QEE factory archives along with Langevin, Electrodyne, Sphere and dozens of other rare vintage console and outboard brands.
The new large format copy system is up and running so accessing copies of original hand drawn schematics and related service docs going back as far as 1942 for some of the really hard to find Langevin gear is a relatively easy task now.


Thank you,

Ken Hirsch / Director of Engineering
Orphan Audio www.orphanaudio.com
Quad-Eight Electronics www.quadeightelectronics.com
Electrodyne Audio www.electrodyneaudio.com (a division of Orphan Audio)

"Education is the cure for everything"
 
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