Wurlitzer 1700 Amplifier

Hi All,

Sorry about the long story, but I am seeking some advice.

My Wurly 1700 was sounding a bit unclear, so, following advice, I have had the amp recapped. Unfortunately in Australia, no jukebox technicians are available, so I found a professional guitar technician who carryed-out the recap work. This guy is a professional with all the sound equipment and his own store. He also replaced tubes 12AU7, 5U4 and both 6L6. He also replaced some resistors.

Unfortunately the sound is now worse. It now has a very harsh sound. The ballad songs (such as Elvis's love me tender), sound fine, but any rock n roll sounds terrible (say old songs from Leslie Gore etc). The Bass and Treble dials make only a minimal difference.

The Technician is at a loss but wants to help me resolve this problem.

Can anyone suggest what he should be looking for? He assures me that the caps and resistors are correct and that the old tubes were very weak.

Any guidance greatly appreciated.

Kinds Regards

Gordon.

Hi Gordo--
I would suggest that you only play Elvis--I mean, come on now--"It's my party---" ?
Anyway--If my memory serves me, the amp on the 1700 uses an external power supply. This, if used would be a box, sitting up against the rear lower door almost under the coin gear. If it's there, it may, or may not have a 5U4 tube( "valve" to you) in it, but it will have several caps (in "cans") that should be replaced.
HTH,
Ron Rich

Ron, the 524 amp is self contained -no external PSU.

What may be happening is that the Cobra pickup has dried out damping material and the stylus/vane resonance is now showing it's ugly self.

Also, this pickup will get doubly ugly if trying to track a stereo record.

The combination of these led to may converting to a magnetic pickup on all the Wurlitzers I owned.

Rob/NYC

Hi All,

Thanks for the replies.

Yes, the power comes into the amp, all one unit.

As an update......If I turn the HF swith OFF, the harshness is much lower, but, the price I now pay is a loss of clarity. However, the Bass and Treble work better. Does this provide any clues?

With the HF switch off, it is probably back to where it was before the work.

And I agree, 'It's my party' is not a good choice of song, but demonstrates the problem. With HF on, it sounds like the windows are going to shatter.

Regards

Gordon.

When I had my 1700, I remember it was the first time I had encountered POSITIVE ground can electrolytic capacitors.

Have your tech check that.

Ken,
If that cap was installed "backwards", he would know it by now !!! (NO--Do NOT axk !!) Ron Rich

That "screechiness" is a classic symptom of dried out damping in the pickup. When I was trying make some sort acceptability I would partially refill the area at each side of the vane with either silicone gel or lithium and clear off any residue from the stylus tip.

Another person suggested a loose cotton instead, that might work also.

Rob/NYC

Guy's,
Dow-Corning # 5, heat sink grease, works very well for that purpose. Ron Rich

Thanks for the advice.

My problem is that this juke was working 2 weeks ago, although the sound was a bit muffled, it was usable. Now, it's not so enjoyable.

I think my best option is to return it to the technician and request that he 'go over his work' to see if something has been missed.

Regards

Gordon.

Gordo,
Maybe yes--maybe no--those carts "go dry" real fast---
Ron Rich

Hi All,

Please excuse my lack of knowledge. I think you are onto something with the needle.

I have a brand new Astatic /cartridge. Around the needle is packed with a white grease substance. Do I remove this?

Also, how do I pack around the cartridge? I currently have a cotton wading around the existing cartridge.

I have put the new needle into the tone arm with good results, but if I pack it correctly, it may improve more.

Thanks everyone for your advice. The sound is noticably better.

Regards

Gordon.

Hi Gordo,
No--leave that white stuff there--it should be "packed" between the needle shank and the plastic side of the cartridge--metal should NOT touch plastic. It gets "dirty" and very "hard" after a while, and should be replaced--Ron Rich

Thanks Ron, Your help is appeciated.

I'll run the juke for a few days and let you know.

Kind Regards

Gordon.

Hi All,

Thanks for the above advice.

I have replaced the Cobra cartridge with a new one. It sounds much better and I guess I can live with it. I have run it for a few days.

I will need to replace some records that still sound harsh.

Rob-NYC advised 'partially refill the area at each side of the vane with either silicone gel or lithium', I'm not sure what he means by the vane.

Is this around the needle itself? Between the needle and the red/green plastic of the cobra?

Again, thanks for taking the time to respond and hopefully the sound will improve.

Regards

Gordon.