Help -- EAD PM1000 and REL Strata III experience?

When I turn off my amp, I get a loud hum, unless I turn down the volume, from the REL. My understanding is that the PM1000 has no grounding, due to its internally bridged design (dual differential?). I've contact EAD and my REL dealer, but no luck yet. Has anyone experienced this with my combination. I tried lifting the ground with a cheater plug, connect REL's grounding lead to the PM1000 chassis screw--still the hum. I have yet to contact Sumiko. It's my last option.

Thanks for any help.

I also have a PM1000 and a REL Q201 sub and am having the same difficulty with hum. I contacted Sumiko-they were not able to give me a solution,neither was EAD. I am about to have an electrician check the grounding in my 100 year old apartment , I thought that the outlets are not grounded properly, when I plug in a surge protector with a test light for grounding the test light comes on. I will let you know if that is the problem, although my system is totally clean otherwise.
Please let me know if you find a solution-Thanks
I had a simular problem with a Citation 5.1 and a Rel Storm. After contacting sumiko I got a hold of one of their tech support guys who helped me. I believe a 201 still has the "rel cable" If so try attaching the red and yellow leads to the + and - of the same chanel and the Black wire on the - of the of the other channel. Also you can attach the red and yellow cable to the + of one side and the black wire to the - on the other side. I fooled aroung with many different connections and was told that one will eventually work. If this doesent work please let me know and I can send you some more suggestions.
Vongwinner and Richm53,

Thanks for the posts. I will try Vongwinner's suggestions and let you guys know the results.

Have a nice weekend,

I have the same thing with the REL Storm III. Did not happen with my old amp, but does with my Blue Circle. I just turn the sub off before the amp.
I never noticed any hum from my REL Storm because my PM1000 is always on. Now I tryed some different set up and I am getting this hum only in one case - if Rel low input not connected to my Ovation. Is your low unput connected to your preamp?
If not try it or at least ground the outer contact of low input.
Please let us know what is the result.
BTW what is your Rel set up (phase, volume, roll off)?
I had a hum with my REL Storm and I figured it was because the thin unshielded cable out of the amp into the sub was picking up radio frequencies. If there is a way to shield the cable the answer may be there. I was careful to route the cable away from power cords and such and that did the trick.
It is definitely a ground hum, not RFI.

After a long week of work, I finally got a chance to fool around with the "Rel Leads" connection. No luck. I tried different combinations as Vongwinner suggested and the hum noise persisted. I'm a at a loss. My dealer told me that he'll check with Sumiko. I guess we'll see. Thanks for everyone's postings. Any more suggestions?

Have a nice labor day weekend, (for the U.S.)


I don't know if anyone is still checking this thread. Nonetheless, here is the result of my conversation with Sumiko.

According to Sumiko, to get rid of the hum on an EAD Powermaster 1000, connect the "black" lead to any inexpensive RCA connector, and then use available RCA connection on the preamp. Make sure you connect the "black" lead to the RCA connector's ground signal (outer portion). I haven't tried it yet. But the ultimate suggestion was to leave the amp on, which is better for the amp any way.

I hope this helps. If anyone tries this method, please share your experience with the group.

I had a hum challenge with my REL B-1 sub. I called sumiko and I ended up moving my REL cable away from my other power cords and I also connected the black wire (per sumiko's suggestion) to a screw on the chassis of my amp.

No more hum at all...

I love my REL now!