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[althemusicwizard]

[James Perrett]

Studio Magnetics were at the absolute bottom end of the market for large multitracks so it is no surprise that they use a strange wiring system. The same people made the ACES multitracks in earlier years and I believe they may have had a hand in the Soundcraft machines (but I'm not absolutely sure of this).

I wouldn't advise the wiring scheme that you suggest as there is a big possibility of crosstalk between the channels sharing the same pair. I would use one pair for each channel - you never know when you might want to replace the machine with a properly balanced machine. I would also solder jacks onto the cable at the other end - you'll be thankful you did when you come to change things around.

Cheers

James.

althemusicwizard wrote on Tue, 31 October 2006 10:25

Hi, I've just bought a 1990 Studio Magnetics 2 inch reel to reel. As someone who last used a reel to reel 10 years ago (Fostex R8, G16S) this is all quite new. I'm impressed by the ease you can get to all the parts you might need to service, and the also the pro build qulaity of a machine like this....a bit of a step up from the R8. Anyway,..... I'm trying to wire up the 2inch. The inputs and outputs are on UNBALANCED XLRs, with the following pin configuration. Pin 1 Ground Pin 2 Unconnected Pin 3 Hot (+ve) There is also a 50 way D-type connector (about 55mm in size, I haven't seen one like this before, but it is a 1990 recorder, anybody know what that type of connector is called....it's not an EDAC) which would take all inputs and outputs and is wired in series to the XLR sockets. This would have to be a female connector on the multicore as it is a male connector plate on the back of the machine. The same type of connector is used for the remote for the tape machine, and the diameter of the cable used there is about 12-15mm. Would I be OK in using a 24 way BALANCED multicore using the pair in each for each couple of inputs? So the first 12 lines would feed the 24 inputs, and the next twelve would take the 24 outputs.  I want to terminate the multicore into a jack patchbay....would the best way of doing this be just to solder straight on to the connections of the patchbay rather than trying to solder 48 mono jacks to the multicore. Cheers in advance for any advice, Al

[althemusicwizard]

 

[ssltech]

The Studio Magnetics machines did look a little like the Soundcraft machines, but they had no connection to each other. In fact "Saturn" was the name of the company which spun off from the old Soundcraft machines (taking their name from the "Soundcraft Saturn" which was the follow up to the last Soundcraft machine -the series III?- which was developed shortly before Soundcraft decided that the profit margin in tape machines was simply not good enough and abandoned that product line)... they had some more involved transport servo arrangement called "COLT": -Calculated Open Loop Tension- and they were never a great success... Most people remember the VU meters on the remote as a nice idea... but the meters were about a half-inch in size, and the movements in them were worse than useless, so think "gimmick" rather than "feature".

Studio Magnetics machines were made in Shrewsbury -only about a couple of hundred yards away from where I was born, in fact, by a company originally known as 'ACES'.

ACES console:


ACES got such a bad name for making such complete garbage that they changed their name to 'SECA' for the consoles (Aces backwards... oh yeah... -that'll fool 'em!), and 'Studio Magnetics' for the tape machines. -Same old stuff though. -If you think that's good, then you'd be stunned by Otari... and I think Otari is reasonable but not stellar. -Sounds to me like Studer machines would blow your mind. -That being said, the Fostex R8 was never really more than a toy, so almost anything is a step up.

ACES (later "SECA") consoles were so stunningly bad that the EQ almost couldn't be set flat. Switching in the EQ with the pots set up the middle resuilted in a dramatic response shift of SEVERAL dB...-MEASURED! That stuff really was poor: it made Mackie look like Rolls Royce.

Really, in the early 1980's, ACES were trying to improve their image, and so I answered a 'sits vac' advertisement in the back of "studio Sound" magazine, to see if there was a place for me there... -I was considering my options after a breakup with a fairly longstanding girlfriend and for some reason the notion of returning to where I lived until I was 4 years old seemed worthy of investigation.

However, when I was the factory, and saw how so much of the stuff was "eyeballed-in" in the machine shop, I was a little concerned that this wasn't a very high quality organisation. Rollers were turned on a lathe by an older guy who made only occasional reference to measurement tools, and tolerances were predictably slack. -I might not know any better, had I not also visited the Studer factory, and I can assure you that Regensdorf is a lot different from Shrewsbury!

Unbalanced because it's cheaper. That's the whole story with ACES/Studio Magnetics/SECA. Pin 3 hot for line and pin 2 hot for mic was a British 'standard', also used in Klark-Teknik and Audio & Design gear. -The problem was that until the late 1980's, there was no uniform adoption of any single standard... I used to joke that we Brits liked standards so much tht we had LOTS of them!

If you use twisted pairs with one half of each pair for each channel (i.e. one pair carrying channels 1 and 2, the next pair carrying channels 3 and 4 etc.) you can expect horrendous crosstalk. the inter-conduction capacitance without drain-to-ground in between WILL cause channels it interact in pairs.

-Don't do it.

Incidentally I was offered the job, so I have no ill-will toward the company, but I was so disappointed by the product and the way the company ran, that I couldn't let myself take the job. -As my ife worked out, I'm very glad I didn't... -It's funny what a woman can do to you!

Keith

[althemusicwizard]

[ssltech]

I doubt that they ever made heads. I wouldn't question that they used Otari heads, though I don't know either way.

However, the rollers and guides were turned out on a lathe by a guy in overalls who looked like his next job was making a replacement bolt to hold a starter motor on a tractor...

The metal should polish up if you're careful, but some parts weren't ment to be polished... such as counter rollers etc... they have to have some friction. -If the metal was ferrous (I doubt it) then there could be real rust, but otherwise if it's aluminium alloy based, there'd just be oxidation... Aluminium oxide is actually more stable than aluminium, so leave it alone, unless there's a genuine coarseness to it. Guides and idlers can be polished if you wish, but try not to take any metal off the guide edges... those machines were prone to "weave" in the tape path even before the edges get modified!

I know nothing of the D-sub, but I would suggest using the XLRs. The D-sub may well be cheaper, but you already see the issues associated with using it, and it comes down to a choice between paired crosstalk and a hundred and fifty dollars worth of XLRs... I'd spring for the $150 bucks.

Oh, and by the way... -notice the misspelling of "Professional" in their corporate logo...


Keith

[althemusicwizard]

 

[ssltech]

No provocation taken...

However, at elevated levels, some machines cope better than others.

Heads are reactive components in the signal chain, exhibiting both capacitance and (mainly) inductance. You need a drive circuit which is capable of telling the heads who's boss. If the reflected waveform voltage starts to stray, a low-impedance, high-current output will keep it in check.

Other than that and headroom (particularly if you want to work at higher operating levels such as +9dB/185nWb/m) it's true that the Studer, Otari and other electronics don't stamp much of a thumbprint on the sound. (other than I do remember that the ACES playtback electronics were actually pretty noisy...) -I think (though memory is foggy... this was over 20 years ago) that there may not have been any playback electronics muting... or a couple of other nice touches... Yours may have grown some newer developments since it was a few years later, but overall, the Studers and Otaris had a few nice touches, with Studers having perhaps rather more.

Studer heads are generally accepted to be better at the low end, but be aware that this is speed-dependant, and the dominant aspect of low-end reproduction is ALWAYS the length of the playback head's pole-shoe, unless there's a SERIOUS design flaw elsewhere: -Electronics can and should be linear much lower than  playback head. The high-frequency limit is determined by the playback head gap, again relative to play speed. This is why Repro heads are better-extended at the top end than sync/record heads... smaller gap. -However, you can't record with a repro head, so we live with the compromise.

Transport is important for speed stability, and stuff like azimuth linearity, (both afecting sound performance) as well as tape handling (fast wind packing, speed, accuracy and repeatability of autolocation) etc.

But the biggest thing in any facility, -be it commercial or domestic- is reliability. You don't want to be fixing it every five days, and neither does anyone else.

I'm not really totally "down" on ACES, don't get me wrong. -Actually I'd really love for something from my home town to be proud of... At the moment there's only Carol Decker (from T'Pau) and Charles Darwin that I can think of... and any mention of admiration for either person can start a fight, so I keep schtum about both. -But there really was a difference between ACES and the more expensive manufacturers.

Back in about 1985, there was a studio in Liverpool which bought an ACES console and tape machine combo for about

[althemusicwizard]

[James Perrett]

I did a Google search and happened to come across

http://niceup.com/writers/david_katz/ariwastory.html

If you scroll down you'll see that it mentions Peter Keeling in connection with ACES. Peter also runs a company called The Studio People which you can find at

http://www.studiopeople.com/

I hope that helps.

Cheers

James.

[althemusicwizard]

[ssltech]

Ay yes...

Peter Keeling it indeed was who interviewed me and offered me the job back in 198x...

I'd say if it works, use it. It it's broke, fix it. -Just don't try to make it into what it isn't.

The electronics were at least simple. I seem to remember that the logic was mostly simple gate stuff. Yes it's normal for the machine to use "dynamic braking" by toggling the fast-forward/rewind commands. Studer also used to do this in the A80's and IIRC the A800's by the way, though that practice had ended for Studer by the 1990's, with the A820 and A827. SSLs also control all machines -even those with variable wind speed inputs like the Otaris- through the exact same method. There's nothing to worry about.

I personally never concern myself with VU meter lamps, (I've never heard it make things sound any better, and I can usually read them with or without the bulb) though clients seem to consider them important.

If it concerns you however emove one, measure it. If it has resistive continuity, see if they're all connected in series. If they are, it'll be like fixing christmas tree lights, and -trust me- you're probably better off just leaving them all dark, or you'll be on a weekly quest trying to see which one has burned-out and caused the whole chain to go dark. -It's no fun. High-intensity LEDs might be an option, but we're probably talking ohours and hours of labour making them fit, creating the right DC current conditions, aiming them so they look okay... If you want to do that yourself then fine... if you want to pay a going rate to a tech who makes his money that way, you may well find yourself writing out a bigger check than you thought working meter lamps was worth...

Keith

[althemusicwizard]

[Mixermend - John Godsland]

When I first started in the Pro Audio equipment repair business - I used to look after a Studio that had an Aces machine.......

This would have been around the early 80's - I remember thinking that this machine must have been a prototype, as the mechanics of the transport were quite 'Heath Robinson' (actually that would be unfair to HR!). Changed the actuating solenoids and driver transistors often, as they were always burning out - but didn't have any problems with the audio circuitry. I learnt a lot about tape machines from working on this model - but was not impressed with the overall design.

In the end the machine was traded in for a Soundcraft Saturn - which was actually quite a good machine, well designed and reliable. Another Studio I look after used a Saturn for many years - with only minor problems - the sort of things you would expect in use.

If Keith had taken the job with Aces - things might have been very different - the UK might have had a multitrack machine to be proud of!

I might have some information in my files on the Aces machine - I will check when I open my Workshop tomorrow.

John

[ssltech]

:shudder:

I once worked on a "Cadey" tape machine...

now THAT was the worst machine I ever saw

-It had three revox ¼" pinch-rolers on a non-perpendicular nail...
-the electronics were on veroboard...  

I think that sadly the British tape machine industry would have been no better than the British car industry: Foresigners just got their game together and did it better. -Much as it shames me to confess it, Us Brits didn't really have it together. -Comparing a Ferrograph to a Revox is a bit like comparing an Austin Maestro to a VW Golf... The Foreigners always seemed to do it better.

Keith