500 format Vs Full rack units...

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Mick@ITC
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500 format Vs Full rack units...

Post by Mick@ITC »

Hi all

My question to you techonoligical savvy people is ...if I buy a Pre (say a TG or 99) in 500 format is it identical to a rack format version of the same pre?...just squashed into a smaller space?. Or are they different beasties with different sound characteristics?

Thanks
Mick

chrisp
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Re: 500 format Vs Full rack units...

Post by chrisp »

The 1U rack stuff runs on 48V which translates into +/- 24V rails for the opamps, where the 500 series is standardised to +/-16V rails. Opamps can only swing their output (close) to their power rails, which means that the 1U stuff will have slightly higher headroom for when you crank it right up.

So much for the paper analysis. By the time you've cranked the 500 series to +/-16V signals you've blown up the rest of your gear and totally fried your converters. My understanding is that in the real world the 500 and 1U will sound as close as two 1U units would. Its actually about the form factor - the 500 series lunchbox is more portable than a rack, and uses just 1 power cord for its 6 slots. But a 500 series card just has PCB connectors out the back, so by itself its useless. - you really need that a lunchbox (or console with 500 series slots). The question is rather whether you want your external pres in a lunchbox or a rack, and that's really a whole other equation as to how you work.

In my setup, for example, I have 8 external pres (4 x JLM 99V, 2 x old RCA germanium and 2 x tube) feeding into an ADAT A/D. All fits into a 4U rack. When I need the extra pres, I plug the ADAT lightpipe into my main DAW interface (which sits with some other gear in another rack) and I'm ready to go. So for me to go with the 500 series, I would need a 8 slot lunchbox that comes with an ADAT out. Such a beast does not exist yet (hey, is that a business plan?). The fixed nature of the lunchbox wiring is a hurdle I keep coming across, and so I stick with the rack units. FWIW
Chris P
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I do lots of things. I believe eclectic skills are best.

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Mick@ITC
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Re: 500 format Vs Full rack units...

Post by Mick@ITC »

Thanks Chris

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