New furniture and PSUs
Printed From: Graham Slee Hifi System Components
Category: And the rest
Forum Name: Audio System Set-Up
Forum Description: Discussions about getting the best from your system (Digital section now moved)
URL: https://www.hifisystemcomponents.com/forum/forum_posts.asp?TID=4356
Printed Date: 27 Mar 2026 at 5:06am
Software Version: Web Wiz Forums 12.01 - http://www.webwizforums.com
Topic: New furniture and PSUs
Posted By: ICL1P
Subject: New furniture and PSUs
Date Posted: 04 Nov 2017 at 8:49am
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I’m considering commissioning a piece of furniture to house my kit. The reasons are to hide the mess of cables, remove an ugly underpopulated Hi-Fi rack (small boxes don’t need the space) and to create some useful storage space, which might be used for LPs. TTs would be on a wall mounted shelf. CDT and Majestic would be on top of the new piece of furniture. The new piece would have three shelves. The top shelf would be shallow and would accommodate Proprii, phonostages, switch and R Pi. The middle shelf would be deep enough for LPs, but could be used for other purposes. The bottom shelf would be shallow and would accommodate the PSUs. The top and bottom shelves would allow cable access through the back panel. I think I’m right in saying that it is usually recommended that PSUs are off the rack, preferably on the floor. Here’s the question; what, if anything, would be the downsides of housing the PSUs on the bottom shelf, as I have described? It is a suspended wooden floor in a 19th Century house. ------------- Ifor ===== Reflex M & ACCESSION M, CuSat50, Majestic DAC, a Proprius pair. |
Replies:
Posted By: Richardl60
Date Posted: 04 Nov 2017 at 10:38am
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Vibration/isolation. Until yo7 try it you won’t truly know, but you could try various isolation materials underneath (by ear). You could also try on/off the rack though best avoid carpet (heat). If your gear is permenant the best way of tidying the cables up is to have them terminated to size, mains, interconnect and speakers. The STD PSU mains and outlet are long too and can be customised. |
Posted By: RichieCactus
Date Posted: 04 Nov 2017 at 6:43pm
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I wonder if you could attach some shielding material to the underneath of the shelf above where the PSU's will be ? I've no idea what material or whether it would be effective - but sounds like a good idea !  rgds ------------- Rega RP8/Cartridgeman MM3/Thorens TD166/AudioMods VI/Accession/Croft RIAA/Arcam A85/Quad 21L |
Posted By: ICL1P
Date Posted: 04 Nov 2017 at 7:23pm
We don’t do carpets so that’s OK. I agree about bespoke cable lengths if permanently sited, but I’d not be that certain. ------------- Ifor ===== Reflex M & ACCESSION M, CuSat50, Majestic DAC, a Proprius pair. |
Richardl60 wrote:Posted By: ICL1P
Date Posted: 04 Nov 2017 at 7:24pm
I don’t understand why shielding might be needed. ------------- Ifor ===== Reflex M & ACCESSION M, CuSat50, Majestic DAC, a Proprius pair. |
Posted By: Graham Slee
Date Posted: 05 Nov 2017 at 6:30am
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PSU1's best on floor. This is because of mechanical vibration which all mains transformers produce. The vibration has been known to "induce" 50Hz (60Hz if your mains is that) signal into other things. This might not happen in all cases. But seeing it has it is worth thinking about. The "phenomena" I first discovered 30 years ago when building some amplifiers which had output transformers. I had mains hum on the output. I started removing bits of the circuit until there was no amplifier left - absolutely no connection to the output transformer, but there was still mains hum. It was because the mains transformer was doing what mains transformers do - they're constrained buzzers! The vibration was transmitted via the case to the output transformer which turned it back into electricity! ------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |
Posted By: ICL1P
Date Posted: 05 Nov 2017 at 8:44am
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Thank you Graham. ------------- Ifor ===== Reflex M & ACCESSION M, CuSat50, Majestic DAC, a Proprius pair. |
Posted By: Richardl60
Date Posted: 05 Nov 2017 at 8:58am
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I did suffer bad hum when I first bought my PSU which was located on th3 floor. Why? Cable management of the long cables which were in very close proximity to my speaker cables at the time. Cable length was an issue |
Posted By: RichieCactus
Date Posted: 05 Nov 2017 at 9:00am
Thats interesting... my Accession's PSU IS on the floor ... ... but mainly because I've run out of rack space. My Rega TTPSU is sited as far from my turntables as possible - as directed by Rega. I've always understood this was to minimize electro-magnet interference with the sensitive TT cartridges. ?(hence my "shielding" suggestion previously) thanks RC ------------- Rega RP8/Cartridgeman MM3/Thorens TD166/AudioMods VI/Accession/Croft RIAA/Arcam A85/Quad 21L |
Posted By: Graham Slee
Date Posted: 05 Nov 2017 at 9:53am
Your understanding is correct. ------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |
Posted By: IntempestaNocte
Date Posted: 13 Nov 2017 at 5:58pm
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I was just pondering this very issue when I saw this thread. I read in a random thread somewhere the other day that it is a bad idea to sit PSUs on carpet. That was the first time that I had heard of this issue and I was concerned as I have had two PSU1s sitting on the carpet under my hifi cabinet for nearly a year now. So I started thinking that I should get something to put underneath them to allow free movement of air between the casing and the carpet. I was thinking of some sort of trivet-like affair and so I ended up looking at some things that are essentially two parallel pieces of wood with doweling connecting them to form a rack. I was just about to buy a couple when I read Graham's comment about vibration and now I don't know what to do. Would this be an issue with such an arrangement? The vibration should pass through the wooden dowels into the wooden sides and from there be absorbed by the carpet, I think... or would the casing rattle against the dowels creating an audible rattle. Anybody got any ideas.  Incidentally Ifor, I've got the exact opposite problem to you as I have a really pretty but critically overfilled hifi cabinet  . It is so impractical I should really replace it with something purpose made but it is the best looking piece of furniture I own.------------- Scott AT150MLX > Audiomods Series V Standard > Rega RP6 > Accession MM > Marantz PM6005 > KEF Q100 / Solo UL > HD540II. Voyager, Bitzie, AgSat90. |
Posted By: Richardl60
Date Posted: 13 Nov 2017 at 9:42pm
| Wood may be bad but unless graham has changed it has a brilliant wooden rack with several PSUs in it so suspect it would be fine otherwise he would have them all vibrating at once! |
Posted By: Drewan77
Date Posted: 16 Nov 2017 at 6:13pm
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Catching up with the forum for the first time in a while (back yesterday from 6 weeks visiting the family in America) - most of my various PSU1s are on the carpeted floor but the one powering both Accession & Majestic is on a small shelf hooked on the side of the main system rack. Reading Grahams earlier post, I guess this is just about the worst place for vibration  so I will move it to the floor before I power the system up again (I turn the PSU1s off for these extended trips; when in the UK, I leave the GSP gear permanently on).------------- Older than I once was, younger than I'll be ............................. Andrew |
Posted By: Graham Slee
Date Posted: 16 Nov 2017 at 8:58pm
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I made two wooden "caddies" carrying 4 PSU1s each for the road shows to save time in setting up. They are fitted with https://uk.rs-online.com/web/p/trailing-sockets-power-distribution/4508946/" rel="nofollow - RS 4-way IEC distribution units and the mains input leads shortened to suit. Rather than taking the PSU1s back out I left them in the caddies and I use one to power equipment in the workshop rack, stood on the tiled floor. I haven't noticed any degradation to the sound. https://uk.rs-online.com/web/p/trailing-sockets-power-distribution/4508946/" rel="nofollow - ------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |