Dual 504 put to use

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Hello everyone,

My uncle at age of 85 decided to put Dual 504 turntable in use for the first time. Yes, it is new in the box :)

He has no speakers or amplifier, so I thought about Edifier R1280T Wired Active speakers to keep it simple for him.

EDIFIER Studio R1280T 2.0 Lautsprechersystem (42 Watt): Amazon.de: Audio & HiFi

However, as these speakers don't have phono preamp I am not sure if they are suitable as is.

I believe turntable has MM cartridge so far greater voltage output, but is it enough?

Kind regards

Marko
 
@Galu

Thank you for recommendation, they look really nice but slightly expensive, he don't want to invest too much.

@Kay

I don't know the answer to that question since I have not yet seen the turntable.

@GeorgK

Yes, after a bit of googling I figured that, so together with speakers I ordered a cheap phono preamp box.

Hama Stereo Phono-Vorverstarker PA 506 (Fur Plattenspieler, Inkl. Netzadapter 230V/50Hz, 300mA, Cinchkabel 0,9 m) schwarz: Amazon.de: Audio & HiFi

126 EUR total, I hope it will serve him nicely. My biggest worry now if turntable will work after sitting for 40 years.

Kind regards

Marko
 
Phono preamp arrived. I opened to install power switch, surprised to see no opamps. Part count seems low for 40EUR :)
 

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The preamp employs discrete transistors instead of opamps, which many users believe give better results.


Thank you Galu, good news then.

I have another question, it seems that turntable has DIN 5 connector on its output and a separate wire for shield. Do you suggest I:

a) buy DIN to RCA adapter
b) cut DIN connector and solder RCA connectors instead
c) change DIN cable for RCA cable and solder on turntable side

Kind regards

Marko
 
It was common on German gear in the 70's to use DIN (45500 norm) for connecting gear, tape recorders for example used the 5 pins as In / OUT, that's why there is one ground only at middle pin. There were straight (normal connection) and inverted cables (for dubbing for example). I own a Perpetuum Ebner turntable (crystal head and AC127 transistors) and a Grundig TK 146 Reel to Reel with DIN connectors.
 
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Provided there is access to a handy tag strip on the underside of the turntable, c) would be my preferred option.

And as sesebe states - the DIN lead may not be suitable for taking two RCA plugs, which would rule out option b).

According to the service manual L&R channel are not separately shielded, see below.
View attachment 710874 View attachment 710880


In reality the stock DIN cable is a twin coaxial lead. Both channels may easily be separated and equipped with RCA plugs.
And yes, there's an easily accessible tag strip beneath the chassis, called the muting switch, where one can solder new RCA leads as well. The stock DIN cable features three 2.8 mm Faston blade connectors.
If you have a close look to the left handed drawing, you see a bridge that short-cuts left channel ground, right channel ground and chassis. If you swap to RCA leads, it depends on the actual (pre-)amplifier and the cartridge grounding whether it is best to leave this bridge (and omit the separate ground lead), to cut the bridge from the chassis, but leave it between the channel grounds, and provide a separate gnd lead, or to remove the bridge completely and also provide the chassis gnd lead, of course.


Best regards!
 
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