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QRK 12c Turntables

foxwelljsly

foxwelljsly

Me too, I ate one sour too.
Was chatting to someone about these these heavy duty idler turntables the other day. They look way chunkier than Lencos, were used in a lot of broadcast facilities back in the day and go for a comparative song these days.

Never heard them mentioned here. Anyone here used them? Any good?

cheers
 
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Sorry, no. Just wanted to see what the beast looked like and posted the photo I found. Looks very well built. I had never heard of the brand before.
 
There are a lot of interesting American broadcast idlers; Rek-O-Kut, Rondine etc. I get the impression restoration can be awkward as American rubber idler tyres, rubber decoupling grommets etc just don’t seem to be of the quality of those on European stuff like TD-124s, EMTs, Lencos, Garrards etc and I don’t think there is the same 3rd party spares market. There’s an interesting Australian one too, huge thing with a 14” platter. Can’t remember the name. All potentially very cool decks.
 
My dream broadcast deck would be a Gates CB-500. Gates were the number 1 choice of North American broadcasters and US military stations around the world. Other than the usual built like a tank construction, what made these stand apart from the crowd was the drive system consisting of a single phase 600rpm motor with the idler engaging a small diameter rim near the centre of the platter. As a result rumble was much lower than was typical without losing out on torque transfer or quick startup times. It didn't hurt that these featured a 1" diameter hardened steel main bearing spindle running within a Chrysler (yes, the auto maker) oilite bearing/bushing (you can stick your finger in it all the way to the bottom during a service).

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Their (Gates's) rumble figure of -45dB doesn't sound good by modern standards, then again in the 301 manual Garrard just say 'almost non-existant' which could be anything!
 
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Looks pretty solid, I can't see why they shouldn't make a decent turntable with due care and attention.
 
wd40addict said:
Their (Gates's) rumble figure of -45dB doesn't sound good by modern standards, then again in the 301 manual Garrard just say 'almost non-existant' which could be anything!
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Well, it was 10dB lower than the NAB standard for mono, and 5dB less than that for stereo. It all depends upon how rumble is measured, I suppose. Starting back in 1953, the NAB standard was -35dB. I wasn't until 1964 that a new NAB standard for stereo playback was introduced at -40dB. As the Thorens Rumpelmesskoppler* was decades away, measurement involved the use of test records (variable reference noise levels right there) and a small combined 10Hz high pass filter/switchable -35dB attenuator. Any deck that measured better than NAB standard was considered to be 'perfect' in this respect. If you think about these measurements as being 35 or 40 dB below record noise then they are indeed far lower than what anyone could be expected to hear, especially so, when we consider noise masking.

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* Rumpelmesskoppler eliminated the need for test records for rumble testing by presenting a stylus platform that was free to rotate (therefore remained stationary with the stylus on) whilst hung from a main bearing spindle extension.
 
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Craig B said:
* Rumpeltestmeter eliminated the need for test records for rumble testing by presenting a stylus platform that was free to rotate (therefore remained stationary with the stylus on) whilst hung from a main bearing spindle extension.
Click to expand...
I would like to see the tone arm lead out wiring for that!
 
Doesn't look like it would be too difficult to knock one of these up. That is, assuming one is interested in listening to rumble vs. music.

I was going to mention how stereo cartridges used to be strapped differently for measuring vertical vs. horizontal rumble in the early days, but then I kicked myself out of it. With idler drive decks, in particular, it would be interesting to note the differences, though.
 
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