Hi,
I live on the 12th floor and have long since dreamt of what my Naim system will sound like without 40 fridges and tv's between it and the earthy stuff.
On a bad day the hicaps can hum like a squadron of Lancasters hooning overhead.
But recently variable RF interference has become a huge issue via my Naxo. Its not great admiring your mana/naim monolith whilst its whining out polyphonic noises even with the volume down. When set to passive 72/hi/250 its fine.--I do get the occasional voice(no they are not in my head) to confirm its RF status.
My system is lp12/aro/troika/geddon/prefix-snaps2/CDi/72/hi/naxo/hi/160/250/sbls.
Intially was thro' the bass driver output--fiddling with the snaic helped(widened the pins a little) but the last week the treble--250(1yr old) has been having ago--even with the signal switched off at the naxo.
-any suggestions (apart from moving-will be in next 6 months).----gratefully recieved.
Mystified as to its variability.Although the transformer noise and system performance has always been a little too tasiturn when everyone is in watching the box. On a really bad day I just retire to the bedroom and enjoy the marantz/rotel/mission system there and forget those 1000's spent.82 on hold till I move.
Shame that video didn't completely kill the radio star.
Cheers Richard
PS Mark from Naim service dept(that outrageously proficient guy)told me about a house first in line to a electricity substation near Salisbury where Naim equipment had reached apparent new levels of musical Nirvana. Who cares about electromagnetic radiation health fears--life would seem long and rich enough with that type of auditory stimulation.
Posted on: 05 April 2001 by Rockingdoc
I use heavy duty RS shielded mains cable, with the shielding connected to the earth wire at the wall-plug end only. The wires are connected normally at each end. I know that it is against the WORD OF NAIM, but it gets rid of a lot of RF crud in my system.
Posted on: 05 April 2001 by David Dever
Without any internal modifications or outlay of cash, you may get some mileage out of the following tweak, which I used whilst living downstream from the radio transmitters on Chicago's Sears Tower (and with a Prefix, to boot).
If you coil your interconnect(s) once under the destination piece of equipment prior to connecting it at the DIN or XLR socket, this creates enough inductance to filter off some RF noise, with the most minimal reduction in sound quality. Coil only once, as too many loops will quickly degrade the sound.
Hope this helps,
Dave Dever, NANA
Posted on: 05 April 2001 by Martin Payne
Richard,
At one point I was suggested to try capacitors across the speaker terminals (in parallel with the drive units).
Since this was at the end of the A5 speaker cables JV deemed this was not a danger to the amps (always a concern with NAP’s & capacitance). I will try to find up the exact values.
Apparently this should somehow stop the RF getting into the power amp, even though they're at the speaker end of the cable.
cheers, Martin
Posted on: 05 April 2001 by Mark Dunn
Hi all:
Sproggle said:
"I think someone on this forum said they had used a Faraday cage with their pre-amp, but I can't be bothered to check. A search might find it if whoever it was doesn't mention it again here"
That was me with my 102 and 'S' phono boards. When I lived in Memphis, TN (moved recently, thankfully) I got bad RF and traced it to the 102. I made the Faraday cage from the aluminium bug mesh that you can buy in rolls from stores ($5 ish) here in the U.S. I simply put it around the 102's shelf in my rack and tacked it on. It worked *very* well.
Best Regards,
Mark DunnÒ
Posted on: 06 April 2001 by Greg Beatty
FYI -
For anyone interested in constructing a Faraday Cage, I found pure copper mesh at Michael's Craft Store. They have it in small pieces and larger pieces.
- GregB
Insert Witty Signature Line Here
Posted on: 06 April 2001 by Richard Paget
Sorry for my tardy reply.
Yours comments have given me reassurance in the confirmation of the power amps being the cause--and not some emerging psychosis. I will attempt to coil away tommorrow--something that will take a while I think--amazing how many bits of black string hang from the back of an active Naim system.As things have only become noticeable recently maybe some repositioning will help.
The capacitors will conflict with my obsessive nature and reluctance to do anything that will degrade the Naim performance. On one of those bad ears days--I'll be wondering how good it would sound without them--a frenzied cycle of desolder/resolder would ensue.But will use this if all fails after the move.Thanks for the plan B.
To be fair to the guys at Naim--i haven't actually discussed my RF problems with them.
The Faraday cage--sounds a little S+M! I remember seeing a programme on the intelligence service in WW2 and saw one on that. Do you get a copper tan thro' copper foil on the windows. I own a 1960's mini rally car that has thin copper foil as part of its heated front screen--gives excellent colour to sunsets as you're bouncing down a stage.
I wonder how much softer RF affects the amps performance.
Interestingly my phono input(prefix) makes no difference to the interference--just the same when unplugged.
I'll let you know if I can still hear 'germany calling'
Regards Richard
