Hi I own RA Evolution 500 powercords…I was considering a signature powerblock…but the price stuck in my throat a bit…so I am building my own…
Using a henly block inside…using 6mm cable…project not finished yet…
Using a henly block inside…using 6mm cable…project not finished yet…
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Great project.
Let me know how it goes.
(Would love to come and see/hear it one day…) 
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Hi Jim very welcome to visit…cheers
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I have got to fill any imperfections…and fit a gland to the side to accept my diy braided powercord …I will then spray the frame with stone finish flecked paint…should look ok. The unit is only 5mm wider/taller than the RA Signature…so its not too bulky for an 8 socket unit. I will be using unswitched MCRU rhodium plated plugs.
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Yes, the RA Powerblock is nearly 2k just for the sockets.
Have you bought bare Kimber cable and you’re going to wire it into your homemade block at one end and fit a UK mains plug on the other end?
From what I’ve read it’s likely that the Rhodium plugs will take some time to run in.
My system has improved over the couple of months it’s been installed - to what extent this is due to the new Lapp radial with Furutech (G) socket or to the new SL2 tweeters I’ll never know.
It can be hard on the ‘down days’, when the system sounds off, to relax and remember that it’s mainly run-in variability.
Thank you so much for inviting me to visit, Rich - I’ll get in touch via @Richard.Dane to discuss.
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I found exactly the same. Removed the hum completely and initially I thought the sound quality remained the same but after extended listening I felt something had changed. As well as the sparkle and delicacy you refer to I felt the bass lost some weight and texture.
Will be sticking it on an auction site with a Furutech Clearline I took a chance on.
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An Isol-8 Powerline Axis mains block completely removed transformer hum in my system. It certainly hasn’t denigrated the performance, possibly enhanced it.
Not the cheapest DC blocker mind but I needed a good 5 socket mains block anyway.
G
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I was full of anticipation as the ‘hum’ is a little annoying, however too much of a compromise…
We tried…
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I have been fighting the hum for a while now. Worst offender was my NAP300DR PSU to which i attached an Audiolab DC blocker three months ago, which helped but did not cure. Most recently i realised i was getting hum not only from the NAP300 PSU but also some from an XPS DR PSU and most surprisingly my 3 year old Rega Aria phono stage was now the loudest!
So i have now purchased a high-power DC blocker from ATL Audio that has two UK socket outlets and this now feeds my two power distribution strips (and removed the Audiolab device). The silence is refreshing! I can still feel a slight non-audible vibration in the case of the Rega but the two Naim PSUs are still at last. Listening to music i cannot yet discern any reduction in audio quality by running all the power through the ATL DC blocker. HIGH-POWER DC Blocker Trap Filter, 2 AC Outlets – ATL Audio Ltd.
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Hi @kwhitmarsh the ATL DC Offset circuit is more less identical to my own filter design, mine does not include the 22ohm resister, but I suspect that will change in the near future.
One thing to keep in mind is transformers do want to vibrate & it can be audible to some extent.
My Naim transformers all hum, but are only just audible in night time silence & within 1m distance.
Finally my hum levels reduced even further a year or so ago when the local national grid voltage was reduced, mine went from 248/252v to 238/242v.
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something strange is that the hum was not constant, but only during some hours of the day and of the night. it was getting me mad as I could not hear the music well during the night.
I bought IFI dc blocker, solved 90%, strongly reducing the hum, now to hear it I have to get very close to nap 250. moreover both hicap dr and nap 250 were humming, I put the IFI only at nap 250 and also the hicap is not humming any more.
I cannot say it impacted the sound and is very small, smaller than other DC filters I saw.
anyone thought about possibility to bring devices to assitance? at which level of hum a device should be brought to assistance?
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This is indicative of some form of pollution, probably DC, and if the iFi device helped, it most likely is. But it could be just noise from nearby loads, or issues on your local supply.
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I almost didn’t dare post my experiences with transformer hum- SN3 and HCDR!
But- I have become irritated by variable transformer hum from both these components and after following all the advice on the forum concluded it must be dc offset.
I purchased an ifi dc blocker and it made absolutely no difference at all. I concluded that the component was insufficient rather than questioning the diagnosis so it went back for a refund
I then saw a isol 8 axis dc blocker for sale at less than half retail so bought this.
This too has made no difference to the hum- so I owe ifi an apology.
However- the sq seems to have improved- more width depth and height to the soundstage and bass tighter. I may be imagining this and trying to justify the purchase of a new box- who knows?
The hum continues unabated so I think I will just have to cope with it!
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I assume you have been through everything in the following thread?
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Sadly yes. I have concluded that I just have been unlucky with a humming transformer.
It’s the same when I tried it in a different plug socket in a different room in my house and also in a different house.
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In fact I must thank you because I have just realised that you wrote the authoritative guide on this subject!
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It is a subject that comes up so often, and no-one was putting all the combinations of responses together. I’m just glad to help people. I still have some hum, but not enough to worry about
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Try the above, a Excelsior DC Blocker MKII. I had hum problems with a XPS DR and a 555PS DR, until I used one of these. My listening position was close to the power supplies and the hum was noticeable, unless played at thrash metal levels. After fitting, I could play at low level and not notice any hum.
P,S. If anyone has a strange fetish or obsession about placing your ear next to the power supply, then you will most probably still hear a very low level hum emanating from the power supply still. 
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I believe MCRU offer a 30 day money back guarantee.
Just ask them how many Naim or other manufacturers owners have returned one. Be prepared for laughter at the other end of the phone
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