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Colibri or Hummingbird?

Hi all,

I'm experiencing a rather annoying 'hum' with my Colibri XPW cartridge. It sits in a Reed 3P tonearm on a Micro RX-1500 and goes into a Boulder 1008 Phono amp (the Reed tonearm cable has RCA plugs, so I'm obliged to use the Boulder's RCA-XLR adapters). The hum is typical to the Colibri/Reed combo. The two other tonearms I use on the RX-1500 (one of which also goes straight into the Boulder) are completely silent, no matter what cartridges are used.

The hum resides in the background while the arm is in stationery position, but it turns into a fierce 'humming' the moment I touch it, again retreating to the background when I release the arm. Strange enough this problem comes and goes and had almost completely disappeared for a while. But for some reason it has returned again, without having made any changes in the system.

It's a complete mystery to me, so I hope some of you might be able offer some explanation. And if possible a way to get rid of it.....


edgewear
sbank's avatar
sbank
3,378 posts
 
How is the problematic setup grounded? Have you tried the Colibri on the other arms and gotten no hum? Cheers,
Spencer
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rauliruegas
12,865 posts
 
Dear @edgewear: Like Spencer sid seems to me  groun problem tht could be nywhere from the Reed tonerm female cartridge connectors to the IC cbles connectors. Somewhere in between exist a " cold/loose  solder tht sometimes is ok nd sometimes develops the problem. So you need to check ll the wiring/IC cbles connector termintions trying to look for tht ground problem. The orienttion/position of the IC cbles could help  little but the problem will not disppears totally. You need to check those contct connectors including the tonerm ground one.

R.
edgewear OP
543 posts
 
Thanks for your suggestions, which have helped me to narrow down the problem!

Although it is definitely not my idea of fun, I dismounted the Colibri from the Reed arm and put it in a SME type headshell in order to be able to try it on both my other tonearms (Audiocraft AC-4400 and FR-64S), using the same turntable and same phono amp.

In both cases no hum at all, which seems to indicate - as you suggested - that the issue is with the grounding of the Reed tonearm wiring or its cinch connectors. Or possibly the Boulder RCA-XLR adapters (which consist of female RCA's, a short length of wire and male XLR's).

I will have the tonearm wiring checked and perhaps consider to have the cable re-terminated with XLR connectors, bypassing these adapters altogether.



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rauliruegas
12,865 posts
 
Dear @edgewear: The best is what you said: to have reterminated the cable with XLR connectors. Those adapters are really degrading the quality performance level of that lovely Colibri or any other cartridge.

R.
edgewear OP
543 posts
 
@rauliruegas,
I agree that these adapters should be avoided, but Boulder has only XLR inputs and I already owned the Reed arm before changing to these amps. I did inquire about the possibility of re-terminating the Reed cable to XLR connectors. The Reed distributor offered to do this for €750, which I found ludicrous and 'respectfully' declined. Should I reconsider this offer or should I try finding someone else with the required skills who might do this for a more reasonable sum?
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