Technics SP10 Club (SP15, SP20, SP25, BBC' SP's and SP10R’s also welcome)

[stratokaster83]

They look very nice 

[warrjon]

They sound better than they look. I was astonished at the improvement these platters made over the stock one. So good I will most likely make a few more for those who want them.

I have a couple more upgrades like adding Dynamat Xtreme to the bottom of the Gunmetal to dampen it further. Then to do some measurements to see if I can measure why the Gunmeat platter is so much better than the OEM. I have done impulse tests and the SS/GM do not ring as long as the OEM.

[innernerd]

Didn't the mk3 have a gunmetal platter several kilos heavier than the mk2?

[stratokaster83]

Didn't the mk3 have a gunmetal platter several kilos heavier than the mk2?

It was a 3-layer construction: butyl rubber -> diecast aluminium -> solid brass

[warrjon]

I made a SS/Delrin platter for someone in Sydney. This is on an SP10mk2 Kaneta, he also has an SP10R on a MinusK and from his reports the mk2 with SS/Delrin platter betters the 10R.

Platter 19mm Stainless with 16mm Delrin with LP label recess, total mass 11kg.

[stratokaster83]

I'm not sure I would trust the bearing to support 11kg, mk3 had a massive bearing compared to mk2...

[warrjon]

If it was an Idler or Belt drive I would agree but being a DD as long as the platter is balanced there is no additional side load on the bearing. There is additional load on the thrust pad but this is no different to the mk3 as the pivot at the bottom is a single point so the load on the thrust pad will be similar.

The mk2 was also built to run 24/7 in broadcast environments so the any additional wear on the thrust pad in a domestic setting is negligible, and the trust pad is easy to replace and inexpensive.

The improvement is massive it makes a Kaneta style mk2 in a resin/bentonite plinth out perform a 10R both have SME IV tonearms.

[Simonm]

Snap  

My understanding is that these SP-10´s with variable speed control are ex-BBC units. Mine has a sticker on the base with a service history. Will try for a picture when I´m next out in the listening room.

The turntable is modified and won´t run without the variable control attached.

Quite correct: this was a "quick & dirty" BBC design, produced after the RP2/9 and RP 2/10 series. The original configuration included SME II (9"), and a Quad 33 as preamp (mechnically modded so the volume knob needed a screwdriver to operate it). There was also a muting circuit so it could be started with an open fader, and four BBC line amps, two of which bumped the output up to professional line levels and balanced it. Output on hypertac. There wasn't room for the Technics PSU in the woodwork, so that was external, connected by, IIRC. a 5-pin XLR. I have one but it's in a long line of projects presently.

[I THINK - see post below] The reason for it's existence was the need for replacement turntables in heavy-use TV operational areas such as dubbing theatres and studios. I think some went to local radio too (if so, best avoided as they will have been abused probably). A trolley was optional, and the whole thing, although big and clumsy in a domestic setting. was small and easy to move around in a control room, should that be necessary.

I suspect the RP2/10 was finally seen as a glorious gold-encrusted white elephant - mine would have cost more than a family car as ordered from BBC Equipment Department. These ones aren't "BBC Coded Equipment" and I have been unable to find documentation on the design itself, although the line amps inside are coded circuit boards. Although it was made from high-end hi-fi, it would have cost thousands less than the RP2/10 series. I suspect someone in Designs Dept. didn't want to have anything to do with them!

The "starship", dubbing theatre one in Lime Grove, had five of these turntables arranged in a semicircle for the assistant dubbing mixer to use, when I worked in it in 1984. Operationally they were rather a PITA to use, although they sounded wonderful. There was nowhere to park disc sleeves etc, as the perspex lid was made of flat pieces (an inverted tray) and removable rather than hinged - the one for mine didn't survive, and I've never seen one come up on eBay with the lid, either.

And they had a really annoying feature:  In BBC Bristol (note NOT Radio Bristol!) ours were modded with an extra stop-start switch next to the fader, which was properly debounced. So you could start the TT and fade up with only one hand. The aluminium pad wasn't debounced, so false starts were a plague. We also fitted the accessory dashpots to the SME arms, and in our transfer suite (for moving audio between various media), they had decent cartridges too - Ortofon or V15 series, I think - the arm being set up accordingly. The BBC standard SC35C was used elsewhere, as you destroy discs by back-cueing using elliptical stylii (cueing-up being unnecessary in transfer).

Personally I don't think the aluminium plinth is wonderful: when separated from the TT unit it rings like a bell! I shall keep mine though, as the SME cutout and the varispeed mounting position are handy. And when I finally do get to restoring mine, I shall probably use Flashband (bitumen coated aluminium foil for roofs) stuck on underneath to deaden it.

If any ex-BBC engineers know the design history I would be delighted to learn, and have any misconceptions above corrected.

Hope that's useful, S.

PS: If you look at the back of the turntable, the Technics label _doesn't_ say it's a BBC variant (as the RP2/9 and RP2/10 ones are), as it's basically the consumer version, albeit with varispeed.

[Simonm]

The only hint to the origin of my SP10 on the photo:

Arndt

"RP2/MK 75/01"

Wow! I operated more than a dozen of these units in the BBC, I own one, which I have stripped down, and I've never seen any sort of BBC Coded Equipment ID on it. There's usually a small aluminium plate on the back, but these had none. That Dymo label suggests it *WAS* BBC coded equipment after all. That might be enough information for some detective work...

... I hesitate to guess now, but "MK" might be Milton Keynes - the home of the Open University. The BBC operated the OU's broadcast studios for a long time (they were responsible for transmitting OU programmes too), and my own RP2/10 came from there (which was brilliant, because it evidently had very little use). It's possible the design was a cost-saver for the O.U., which then found wider application.

I think "75/01" is a serial number. But it might mean something entirely different. "RP2" means "Reproducer Type 2" i.e. microgroove record players (grams decks in BBC-speak). The older 78 reproducers are prefixed "TD".

I

[wenig watt]

Hello,
I've got this one from GB with a totally destroyed SME 3009 on it. I thought this sticker only said something about belonging to a public fund. An inventory number for electrical equipment that must be regularly checked for operational safety. That would be typical in germany...

Regards

Arndt

[Simonm]

Hello,
I've got this one from GB with a totally destroyed SME 3009 on it. I thought this sticker only said something about belonging to a public fund. An inventory number for electrical equipment that must be regularly checked for operational safety. That would be typical in germany...

Regards

Arndt

You might be right. The BBC Open University Production Centre (OUPC) was in Milton Keynes for most of its existence (I think the OU uses the internet now, and the BBC doesn't make its programmes any more, apart from co-productions for broadcast).

It is possible this is an inventory number (not a serial no. from manufacture copied to the Dymo label), although I would have expected "OUPC" rather than "MK" in the middle. Also, in the mid-1980s, we got better label-makers (beyond Dymo embossing!), and inventory labels were white or silver, with barcodes on them. I haven't looked at the back of my RP2/10 for a while but I think it has one from the OUPC on it.

I have looked up "RP2/MK 75/01" (and a few similar ideas), and cannot find it in the BBC documents where it should be (IF it was a proper Designs Department project).

So I still believe my original theory - that the gram desk from which the SP10 and mounting plate came was made by BBC Equipment Department (in quite large numbers), BUT never had a 'proper' Designs Department code number.

S.

[Slatchmo]

Well here is a friend's rig.
A SP-15 SP-25 presumably out of a radio station in Canada. He wanted a solid plinth and a compact. Stacked laminated wood.
Good machine, easy to service.
The tonearm is a Syntec S-220; sturdy and very well made.
In the end he is quite happy with it, it still needs to be finished, likely varnish or danish oil.

[Chris65]

A SP-15 presumably out of a radio station in Canada.

Nice . It is an SP-25 .

[ilkka313]

I had one of these, ex-radiobroadcast version, made in 1988, w/ EPA tonearm, ultra heavy combination, 45 kg. Really nice unit to use but... Lenco in heavy plinth sounded clearly better so I sold it. Here it is on the way out from my home.

[analogadikt]

I had one of these, ex-radiobroadcast version, made in 1988, w/ EPA tonearm, ultra heavy combination, 45 kg. Really nice unit to use but... Lenco in heavy plinth sounded clearly better