Quickie with slight hum

[denti alligator]

My Quickie has introduced a slight him into my system. Don't have the PJCCS in yet.
I've moved it a couple more feet away from the SEX and that softens it somewhat, but it's still present. Without it the SEX is dead quiet, even at max volume.

Is this normal?

[Paul Birkeland]

Try placing your Quickie on the same level as the SEX amp, and right next to it.

[earwaxxer]

Sam - I get slight hum with mine as well. Sometimes if I touch the RCA connectors, one at a time, the hum may diminish. Its not bothersome but I would say that there will be some hum especially with the chokes installed. When I have the PJCCS installed the hum goes away completely. I personally like the choke sound better though. Damping the tubes helps with other types of microphonics (ringing).

[denti alligator]

Try placing your Quickie on the same level as the SEX amp, and right next to it.

No space for this unfortunately. The Seduction is next to the SEX, since when I put it below it hums even worse than the Quickie. I guess ideally I'd have all three on the same shelf about 1/2 meter apart...

my setup:
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fimageshack.us%2Fa%2Fimg267%2F2821%2Fphotojk.jpg&hash=052e199417555128af209c3c0929189690e64f61)

I get a little less hum putting the QUickie on the floor where it is in the pic, as opposed to on top of the CD player (bottom shelf). It's hard to access there, anyway, unless I (as initially planned) cut the base down.

I had the Seduction down there on the CD player, but it gave me too much hum. Ideally the Seduction would be even further from the SEX, but as you can see I'm limited in what I can do.

(I guess I might consider putting the Seduction on top of the left speaker (in pic) and then the Quickie next to the SEX. Not sure if that would be smart.)

Suggestions welcome.

[4krow]

I would be interested in knowing whether ERS cloth might help. Placing a sheet under the Seduction would be a start. Are you interconnects the shielded type?

[denti alligator]

No, interconnects not shielded.

Where's the cheapest source for ERS cloth? Would that really help?

[Doc B.]

Assuming this is soft, 60Hz type hum, unplug the input cables and see if the hum drops. If so, shielded cables might help if they have good radial symmetry, like coax or really good shielded twisted pair. If the hum stays the same with the cable off it is likely that the tubes themselves are coupling to the magnetic field of the other gear's power transformers. In that case the solution is distance, though you can move stuff around and look for a spot where the radiated field is lowest.

[denti alligator]

I'll play around with it tonight. Would the new Bottlehead interconnects offer the right shielding?

[Doc B.]

I'll play around with it tonight. Would the new Bottlehead interconnects offer the right shielding?

If the problem is magnetic coupling of your cables, yes, they should work well.

[denti alligator]

And if it's the tubes coupling with the transformers is distance the only solution, or might an ERS cloth help?

[earwaxxer]

I would try tube dampers for that - I have found that the dampers also make the sound a bit 'cleaner', although I might be imagining that. For sure they help with the ringing. I made some tube dampers with 3/4" internal diameter copper tubing. Cut it to length and apply a little velcro tape on the inside to take up the slack so the tube fits snug but not too tight. I went an extra yard(s) by rolling on several layers of tin foil and epoxy around the outside, then wrapped it with rubber bands and painted the whole thing black. I also stuffed the tops with ear plugs! Crazy, I know, but I'm done with that!

[denti alligator]

Using shorting plugs in the input, the Quickie is pretty quiet. Just a little hum, though it gets louder the closer it gets to the SEX.

The Seduction is more intense. The hum gets really bad near the SEX. Further away it's still noticeable, but not too bad.

So it's not the cables. Unless of course it's the cable running to the SEX amp in each case. Hmmm....  Impossible to know without ordering some Bottlehead cables...

[Noskipallwd]

Sam,
You might try rolling some different tubes in the Quickie, they seem to vary in their sensitivity to noise. I also keep the Eros at the maximum possible distance from my other gear. All my interconnects are made from DH labs coax, so the BH cables are probably a good idea. I believe the cable they used is of better quality than the DH labs. Right now I have the Quickie right next to the Sex and they are nearly dead quiet. Hope this helps.

Cheers,
Shawn

[Grainger49]

Sam sent me a link to the cables between the Seduction and Quickie.  It is a Belden RG-59U so it is coaxial shielded.