To Aesthetix users

Just a warning here: I understand that you MUST take great care when swapping the power umbilicals here. When you power the Io down and then disconnect the power cables between the Audio and PS chassis, you MUST wait at least 20 minutes before reconnecting these cables or the solid-state regulators in the PS will be destroyed. I tend to take a more conservative approach and wait an hour.

PatrickArmory,

Congratulations. I thought I wrote exhausting posts but yours beats mine by a nose!

I don't have an Aesthetix but I do have an EP15A (love it). I too have a hard time imagining it damaging anything, but then again I had a hard time imagining it making any component sound notably worse - until I heard it happen.

My EP15A improves the sound of every component I own, but when a friend brought his Berning ZH270 over it was clearly happier being plugged straight into the wall. Our line voltage is anything but stable, thus the Exact Power, but Berning advises against line conditioners for this amp and in this case he was right.

Does that apply to your Aesthetix? I have no clue!

P.S. The Exact Power will not filter out noise from dimmer switches, transformers, etc. I spoke to the EP's designer himself. His recommendation for dimmers was to keep trying different ones until you stumble on one that's quiet in your environment. Not scientific but it worked. We also had to relocate the transformer for our 12V ceiling lights that backwash the wall behind the equipment rack. The hum was unavoidable with the transformer within six feet.

Star grounding works well for us. Worth a try and costs peanuts to implement.

Good point Jafox. I don't wait an hour though. Also remember to first disconnect the AC power cable before disconnecting the power supply umbilical.

One other thought about the hum. My SME arm had a DIN-RCA Music Metre silver interconnect that was fine in the first setup. When I moved, this cable picked up hum in the new setup. I tried several well regarded cables and settled on the Nordost Quattro Fil. By far, it had the best shielding (lowest hum). Turns out that it matched ny listening preferences best too.

One way to test this theory would be to simply disconnect the phono leads in to the Io and note if the hum is still there. The next step is to disconnect the hum in to the amo and note if the hum is still there.

Hi guys

I've been travelling in Europe on biz but all these suggestions are extremely helpful. I might also have a bad tube somewhere since the problem is worse in right channel than left when phono is selected, so will try swapping those (maybe the EL-34s in PS) s well as PS cables. Wait an hour before turn-off and turn-on - sounds definitely right with the Io.

The radio reception is there even with the Io not selected. I think it's a cable acting as an antenna somewhere.

I turn off all dimmer switches and halogens when listening to music for the reasons given above.

Will report back, and also Jim White's thoughts when I get him this week.

Best
Patrick

Hi, I have the Io Sig w/VC and 2 supplies. I live in a very RF rich environment near a hospital. On one occassion when trying different ICs I did discover some RF bleed through.No hum with the IO or subsequent RF problems.

Your IC's must be very well shielded and you must exhaustively experiment with dressing the leads and positioning with equipment and try different brands.While not the best, Musical fidelity make a type with RF ferrite clamps on the cable...it may be worth a try to see the result. In the past when I had a Counterpoint head amp this problem would drive me crazy.

Fourtunately the Counterpoint weighed in at about 5lbs so you could wave it in the air and find a good position. Hard to do with the Io.

Also make sure your connectors are scrupuously clean. Any oxidation and the connectors will act as diodes in a cyrstal radio singing through your system.I like the Caig products here not comfortable using any of the silver based contact enhancers as they can be difficult to clean out of the connectors if it does not work out.

I doubt that your electrical system is properly grounded if you had to add new grounded receptcles to replace 2 prong ones. If you have armoured cable or conduit(maybe in NYC) then the outer sheild/conduit may be acting as a poor ground back to the main panel. Get a electrician to seen if you have a "separate" ground wire back to the panel and properly bonded to the neutral at the box. Old vinyl gave good advice on disconnecting and swapping Ic's to discover if the problem is the Io or the amp for hum... working from the source forward to determine the possible cause...don't ignore the dressing of your tonearm cable.

This is exhausting and thankless work but it can be done..goodluck!