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Juha
05-10-2014, 18:20
It was time to try a direct drive deck. I wanted to find
a different and less well known combination of deck and tonearm.

Toshiba SR-370 direct drive

Found one on UK Ebay. This is from 1978. Toshiba made it to compete with Technics SP-10.
What is so special about it. There are many many 80-90's direct drives.
Well, it is the plinth. This plinth is cast out of heavy resin. The plinth weights 15 kg.
Toshiba developed a very non resonant plastic resin.

This is value for money.
How much would one of these cost today?? If you can find a SR-370, it is 100-150 GBP.
Some AOS users have these decks.

Micro-Seiki MA-505
This deck has been paired with various SME arms and Mission 774. SME's are now too expensive. I could
not find a 774.
I did find a Micro-Seiki MA-505 (integrated version) from Japan. The tonearm is a wonder of Japanese
fine mechanics in steel.

The Toshiba deck needed heavy modification for the arm. I had to make a big hole on the plinth.
The cast resin is somewhat brittle so it had to be worked on carefully.
The tonearm came with no connector. There was hair-thin cables with no color-coding.
It was nerve wrecking to solder them. The expensive tonearm had to be worked on.

Testing it now with Nagaoka MP-50, Cyrus 2 Signature edition as pre-amp and CEC 3300 class A amp.

http://hoone.com/toshiba.jpg

walpurgis
05-10-2014, 18:52
Excellent turntable!


Here's mine. With a 774 and ZYX R100 H.

http://i60.tinypic.com/o88bko.jpg

Juha
17-10-2014, 07:30
Ortofon S 15-T on Toshiba SR-370.
The Ortofon dates back to late sixties. It has build in MC transformers.
MA-505 counterweight is way back to handle this 19 gram cartridge.



http://hoone.com/ortofon.jpg

walpurgis
17-10-2014, 09:08
That's actually called an S15T E. I had the S15 T and took the weedy and not very good transformers off along with the casing. That leaves you with what is basically an SPU! I used it for many years, sounded lovely with a decent SUT.

Juha
17-10-2014, 11:39
Even now it sounds special.

Was it difficult to remove the transformers?
Just remove the metal cover - pull out the transformers.

Did it involve soldering new the head shell cables directly.

My Ortofon is second hand from late seventies. Did not like the sound then, put it away.
Now turn it into a SPU:eyebrows:

walpurgis
17-10-2014, 11:48
Was it difficult to remove the transformers?
Just remove the metal cover - pull out the transformers.

Did it involve soldering new the head shell cables directly.



It was quite easy to do, but requires great care. I just removed the casing by prying it free and unsoldered the fine transformer wires from the four pins at the back of the cartridge structure. If it's similar to mine (it looks identical) you'll find two mounting holes in the assembly which can be used to mount it in a headshell and the existing pins will accept cartridge tags.

Bear in mind that the value of the cartridge may lie in its originality. That didn't bother me personally and I ended up with a very fine sounding MC.

Juha
17-10-2014, 13:36
So after opening it would look something like this:

http://hoone.com/ortofonspu.jpg

My next problem would be the SUT. I only have Ortofon STM-72.

walpurgis
17-10-2014, 18:56
So after opening it would look something like this:

http://hoone.com/ortofonspu.jpg

My next problem would be the SUT. I only have Ortofon STM-72.

Yes. That's how it looks.

The STM-72 is nowhere near good enough. I've been using an Osawa OS-100T for the last thirty years. I've not come across a better SUT so far. The Fidelity Research FRT-3 is a very good sounding little unit. I used one of those as well for many years.

struth
17-10-2014, 21:22
Yes. That's how it looks.

The STM-72 is nowhere near good enough. I've been using an Osawa OS-100T for the last thirty years. I've not come across a better SUT so far. The Fidelity Research FRT-3 is a very good sounding little unit. I used one of those as well for many years.

Thought you sold that Geoff?

walpurgis
17-10-2014, 21:25
Thought you sold that Geoff?

I did. It was excellent, but I had a set of ART SUTs and the Osawa too, so I let one go.

struth
17-10-2014, 21:38
Ah, I remember one for sale and was going to buy it as it sounded good.

Found it on a google search...Nice little unit that....

Juha
18-10-2014, 14:25
I tried removing the integrated transformer from my Ortofon ST-15T E.
It did not work out this time.

I dismantled the metal cover from the cartridge.
Now I had black plastic with a removable cover on the bottom.
I peeked in and there was a sub-miniature transformer and bare needle cantilever, magnets etc.

http://hoone.com/ortofonfix1.jpg

There was no way to separate needle from transformer.
So back with metal cover and attached on an Audio Technica 10 gram magnesium head-shell.
Now it was even heavier than before.

I must say this was absolutely good fun.

http://hoone.com/ortofonfix2.jpg