Haufe trannies for 103Pro

[Dave Cawley]

Well I have the Denon agency now, Dave has his lathe and mill set up from yesterday (when he had some big mates round to help him move things). Now I just need the information from Chris, then a few more weeks and we are there!.

There should be less than no hum, so we need to look at this carefully. I'm tempted to run the Haufe in fully balanced mode, that should be good!

Dave

[Marco]

Good news, Dave!

I may have an Earth loop somewhere, I'll bring my preamp (and SUT) as well as my T/T when I come down. At the moment it appears that the Jelco tonearm cable is particularly sensitive to hum pick-up when connected to the A23. As I said, I didn't have this issue with the previous cables that were used on the Technics arm.

I'm sure we can get to the bottom of it, though

Marco.

[scoobs]

Hey Marco
I had a bit of hum with my new Jelco arm running into the A23, after a few failed combinations I ended up connecting the tonearm cable earth fly lead to the earth lead on the A23 and it killed the hum stone dead. I'm a happy camper now.

Happy new year

[Chris]

Dave,
I have sent you the details. Nice to know someone technical is on to them and hopefully will get even better results. Floating balanced earths are not my forte. I prefer bacon sarnies.
Keep in touch,
Chris

P.S. A public thanks to Historicus for having put me on the trail.

[Marco]

Hi Scoobs,

I was hoping you'd be on so I could ask how you managed with your Jelco/A23. I hadn't thought of doing that with the Earth wire, so I'll try it and let you know

Hope you had a nice Christmas - and yes, have a very Happy New year

Marco.

[Marco]

Tried connecting the T/T Earth wire straight to the Earth wire on the A23, bypassing the preamp altogether - it's better, but I still have intermittent levels of hum depending on how and where the Jelco tonearm cable is positioned (it can get really loud when the cable is positioned a certain way, or reduced to a faint hum when the cable is at its 'optimal' position in terms of placement). Weird...

I guess there may be an issue with the particular cable I've got. Not to worry, I'm sure Dave will be able to sort it

Marco.

[Dave Cawley]

Hi Chris

Yes, I will investigate thoroughly, some people call me obsessive...

And Marco, yes I can sort anything out! See you soon?

Thanks guys

Dave

[Marco]

Hi Dave,

I'll pop down when you've got the new mounting plate thing sorted. The armlift still isn't quite right, so we can kill two birds with the one stone. Just let me know when you're ready

Marco.

[scoobs]

Tried connecting the T/T Earth wire straight to the Earth wire on the A23, bypassing the preamp altogether - it's better, but I still have intermittent levels of hum depending on how and where the Jelco tonearm cable is positioned (it can get really loud when the cable is positioned a certain way, or reduced to a faint hum when the cable is at its 'optimal' position in terms of placement). Weird...

I guess there may be an issue with the particular cable I've got. Not to worry, I'm sure Dave will be able to sort it

Marco.

Have you checked that the tonearm cable is pushed to the hilt into the arm base socket, it's a tight fit and needs a good push. Additionally check the small spade connector on the end of the arm cable earth fly lead as it may not be soldered very well (if at all), mine simply fell off when I handled it, so I left the fly lead bare ended and wrapped it around the end of the A23 earth.

[Marco]

Good tips, Scoobs. I'll double check both and let you know

Marco.