Wheatstone SP-6a

[TheAngryFedora]

Hey,

I may have the option of picking up an old, busted Wheatstone SP-6a. At no cost. It's been living underneath a stage for about 6 years I think, and I believe that there are a few major problems with it. I'm not quite sure where, though. Once I get it out, my plan is to take a look inside and see if I can fix it using my limited electronics skills. If not, I'd love to cannibalize it.

My question is: how are its innards? Input channels? Preamps? EQ? The research I've done around here suggests that it's a solid sounding board, but nothing special. Anything that's still manufactured today that sounds comparable in quality so that I can have a frame of reference?

Thanks so much!
-Ben

[Kronos147]

Hi Ben,

I am afraid the information sources on these boards are quite scarce. I own a few Wheatstone TV-600's, and I saw an SP-something when I bought a pair of my boards. I almost thought it was a TV-600. The frame looked similar, the channel cards look similar, the difference being the integrated vs. modular fader packs. The TV-600 keeps a separate bay for the fader packs, and they have options like Mix minus and remote muting. The is probably one of the differences in the boards.

On the TV-600 the channels have 25 pin D-Subs (one only on the mono inputs) on the module itself for I/O, but another 9 pin D-Sub on the frame per slot. This interfaces with the fader pack bay on the console.

I have had a few people who are in the know look at my console. They are all impressed with the simplistic nature of the design. The channel cards are very easy to work with vs. a (dual layer) channel card with mic pre and dynamics and mega groups and fully parametric EQ. From a 'will it blow up/what does it take to fix' standpoint, it is quite simple. If a resistor goes, you see it, and you can beep out individual stages of the card fairly easily (from what I saw and heard, I am not proficient in that regard).

Sonically, I have been very impressed with the console. I loved the sound right off the bat. On the mono cards the EQ is not my favorite EQ ever, but a friend says we can change the sound by changing some part values and IC chips. the TV-600 is hi and low pass filter, shelf low end with gain and freq select, same for the high end, hi shelf, and the mid is a bell with gain and freq again. The Q sounds kind of wide on the mids, making it hard to find the center of something and just notch it out. I have to insert another EQ for that. The EQ on the stereo cards has a low shelf at 50 or 100 HZ, hi shelf at 5 or 10k, and a mid parametric with bell switch for narrow/wide. Would be a cool mod for the mono channels.

I have 16 MI-64 channels, which are mono, 4 stereo bus, and no mic pre. I have 8 MI-68's which are mono, 8 mono buss, mic pre included channels. I didn't wire the mc pres. While there is a transformer in the input, it is balance compensated on the outs and I really want to have a playback only mixer. Tying up an input to use it as a pre sounded like a bad call for my configuration.

Dave Hecht, a member of these boards, came out one afternoon and spent some quality time checking my '600. He found a .25 db variation 20-20kHz. That is pretty damn respectable in my book. I run a custom box with discrete op amps and transformers on the main inserts pretty much 24/7, and that makes it even more spectacular in terms of detail and depth.

One more benefit of the Wheatstone's configuration is that the frame slots/channels are EXACTLY the same as an API. If one was to choose a frame to modify into a 500 series type mixer, these would be a good choices.

I have two '600's sitting in the lounge on their side. They are 56 input (stereo modules, which function fine as mono as well). I wish there was a studio near by that wanted to use one. At some point I will have a custom discrete master section for it (already commissioned) and I can't wait to hear that!