diyAudio (
-   Analogue Source (
-   -   How to wire up MC step up transformers (

Salas 13th July 2011 09:00 PM

They probably meant the shunt load resistance on the input of a direct electronic connection MC preamp. If they said with SUT they meant the reflected value to primary. You should not put any series resistor nowhere whatsoever. Try the secondary to your 47K MM input, listen, then put a 10K across the secondary, listen, that will reflect ~230R, parallel another 10K, that will reflect ~125R, listen. What ballpark you find better you can try tune around.

merlin el mago 25th October 2011 02:59 PM

Wich one is the input? the red or the white/yellow?

kevinkr 25th October 2011 03:10 PM


Originally Posted by merlin el mago (
Wich one is the input? the red or the white/yellow?

See post #2 if you are talking about the 977..

merlin el mago 25th October 2011 03:30 PM


Originally Posted by kevinkr (
Checking old photos I'm pretty sure the red pin is the output and the gold/yellow is the input.

Yes I'm talking about partridge 977, thank you Kevin.

DL103R (0.29mV output) + Partridge 977 + Puresound P10 MM 40dB, I suppose that I need more gain than 1:6 or other MM with more dBs, the Puresound isn't mine but I have on hand to hear now, the Partridge is for the Salas Valve Itch 48 dBs so mi question is: will be enough gain?

coolmaster 26th October 2011 08:00 AM

That builtup unit shows solid core wires to the RCA sockets. I wonder if thats a good thing. I read various methods good for it, twisted pair, and the use of low capacitance but high grade hookup wire. Speaking about wires, I had thought about the use of suitable mouse wires, wires from IDE cables, wires from printer cables, those sorts that are bang for the buck, easy to find and most of all cheap. If these wires are excellent for data transfer, quite high grade copper or even silver plated, it should be great for these tiny voltages and current for moving coil use in this project.
My pair of Cinemag transformers are coming and I've been seriously looking at many options.

dady 12th October 2012 08:31 AM

Balanced connection for the 977?

Originally Posted by kevinkr (
The diagonal wire is the ground for input and output. I would need to check mine for the input and output pins, but I would NOT use the meter to determine which is which - misconnection will result in no or very little sound, but no harm either. Edit: Checking old photos I'm pretty sure the red pin is the output and the gold/yellow is the input.

Use the ground connection diagonal wire on each transformer just for the specific channel's cartridge ground and pre-amp ground, and that transformer's case - do not tie the grounds from both channels together! And the arm and your case ground can share the phono pre-amp chassis ground connection. The transformer should be isolated from your chassis box to prevent loops.

Do not overheat the connections, I recommend pre-tinning the wires and tack soldering them to the pins. I have used a number of these excellent transformers and have not run into one that is damaged, but it could happen I suppose if sufficiently overheated.

Dead silent with this implementation. Run straight into 47K without any additional load resistors sounds best to me with the DL-103D and Zu DL-103.

Hi Kevin:
Thanks in advance, I just thinking in buy one pair of this, they looks a bargain by ebay and I watching inside the forum for some experience with this vintage material. The first question is just answered, the quality is good. The second one, is possible to connect it in in/out balanced connection? At the moment, I just rewiring my tonearms to balanced out. My preamp is still unbalanced. But with this focus on mind. Do you recommend that connection?
Kings Regards

kevinkr 13th October 2012 12:45 AM

I don't see why you couldn't use a balanced connection if you would prefer on both primary and secondary. Make sure that you do provide a ground for shielding and the transformer cases. I have not experimented recently with a balanced connection except on the primary and there it did work.

I'm currently running unbalanced, my two SME arms (a 3009 Series II and a 3012 cloned from a 3009) are easily converted, my best arm a Schick is not. I've found no need for balanced connection.

rockdoc 30th October 2012 06:29 PM

Hi Kevin,

what wire would you recommennd for wiring these up? I currently have Altec 4722s and am looking to get a pair of the Partridge 977s. To run with a Lenco PTP/corian plinth/Morch DP6 12" / DL103 or 103R into a (currently) Boozehound phono stage > Welborne Revielle pre amp > 45 parafeed amps > Zu Superfly Soul speakers.

btw I still have and occasionally run a pair of your Mk III Dynas I bought from you way back when, and they still sound great! Switch them in and out with a modded citII when I want bigger power.


All times are GMT. The time now is 12:55 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 17.65%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio