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Post by palace on Jan 28, 2024 13:18:58 GMT
I wrote last "I must think long & hard as to what next".
Well today when I got up, I sat down thinking for nearly 5 minutes.
There is a wood coffee table at the back of my right hand speaker (from listening position) it sits astride my Atlas Magnum power amplifier which is on the floor on MDF double spacer platforms each layer separated by 4 x cotton reel like rubber electric pump or electric motor isolators; on the table sits an MCRU (Longdog) LPSU for the Caiman SEG50 DAC, at the other side an external Audio Detail heater LPSU for the pair of 6SN7 driver valves/tubes in the Atlas Magnum.
The Croft phono stage sits on the table 7"-9" above the Atlas Magnum with it's 3 big transformers, the Cambridge CD4se that I use as a transport sits on top of the Croft on deep isolating spacers to allow ventilation.
Now to get back on track the Croft has holes every where for ventilation so copper foil stuck to the case is out of the question, what else? iron & steel stop 50hz hum, this morning I spied a 14" x 10" shelf with half inch raised rim from a disposed of clothes rack, my magnet stuck, so I put it under the Croft, the spacers twixt Croft & shelf. With the Croft phono stage & pre-amp/amp on full, & with the arm on it's rest, even lower noise from the speakers that can't be heard from 4' away let alone the listening positions. Getting vary close though if the pre-amp is switched to the DAC or CD with nothing plying there is utter silence...
The isolating spacers were described on another forum by "Windhoek" they are essentially transparent "plastic" discs cut from an inexpensive Addis sink protector in various layers & with a single bumper a sticky 10mm wide plastic dome that are used to stop various doors from crashing when shut. If anyone is interested I can expand on their use. Because the cost very little the naysayers on the other forum were out, of course they had never tried them, the thread at this time has 782 entries even some of the gainsayers have joined those using them. I must confess I was very sceptical can't possibly work but for £4 so hey ho. Suffice to say they actually work the effect is surprisingly good I found that blocks of 4 sets/feet of 9 3 x 3 discs 5 layers deep under the 25kg Atlas Magnum on top of the MDF base under the lighter gear layers 4 2 x 2 etc and also used 4 sets/feet under the OTA Rupert stands my OTA Quad 57'S are bolted to. There are undoubtedly better isolators but not as pension friendly.
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Post by MartinT on Jan 28, 2024 13:36:17 GMT
I do so love naysayers who haven't actually tried something. What value do they think their opinion has?
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Post by palace on Jan 28, 2024 16:48:58 GMT
I do so love naysayers who haven't actually tried something. What value do they think their opinion has? Zero squared? |
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Post by palace on Feb 3, 2024 17:54:36 GMT
Today I was cogitating where/what next, I am convinced that all leads act as aerials to ingest RFI/EMI 50hz noise in to the system. except possibly the digital leads since their outer screen/return is earthed as with my digital leads I use quality "F" type connectors including "F" type phono plugs.
My One Thing Audio Quad 57's have 3m TNT type cross connected coaxial UBYTE2 speaker cable & 2m power leads.
I do not know, that being cross connected at each end negates their screening properties.
Earlier I wrapped with foil the left hand OTA Quad 57 2m power lead (that long to allow access behind) there was a further reduction in 50hz hum more bits ordered & will up date as & when.
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Post by palace on Feb 7, 2024 17:23:49 GMT
I have tried to be methodical in my approach to reducing noise, though just now I realised I had not reconnected the leads from the record in on my Aiwa S950 cassette deck to the phono out (recording) of the MC7R preamp (part of Mark Manwaring-white's extensive mods) when I tested the old concept of silencing/blanking phono plugs. I had left the leads plugged in folded at the rear of the cassette deck. I removed the silencing/blanking plugs from the MC7R & connected the thin 6n OCC copper coaxial phono leads again a significant drop in noise, I believe that disconnected at one end as they were they were acting as aerials funnelling in radiated noise.
Silencer/blanking plugs are an old idea I remember Jimmy Hughes propounding them 30 or more years ago where if you removed the centre pin from a metal phono plug & filled the top with copper foil/wire wool it reduced noise when plugged in to spare phono sockets anywhere in the system, they do in fact work.
The music now produced by the Hana ML & Croft by removing extraneous noise is a totally different beast to it's original form as is the digital side much much improved, I have been indeed still am gobsmacked. there is a little more to come
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Post by MikeMusic on Feb 8, 2024 11:17:03 GMT
You're doing more than most of us put together !  Keep up the good work |
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Post by palace on Feb 8, 2024 12:24:36 GMT
You're doing more than most of us put together ! Keep up the good work Thank you, one other thing at this point I forgot to note was the large improvement in speed & monitor screen performance of my PC which is Wi-Fi fed from the screened on 2 sides with card copper foil covered Virgin Hub 4, originally to screen the Croft & pre & power amps from the Hub 4, the reverse is also true I suggest, the Virgin Tivo box unlike the PC is fed from the Hub 4 via a CAT 8 cable with clip on ferrites. How the Wi-Fi has improved eludes me the PC is 15' away from the Hub 4. I can only suggest that there is less radiated RFI/EMI from the 3 SPSU's now screened with copper covered card behind the TV hitting the Hub 4 which is at the side of the TV either that or both less detritus entering the ring main I have for years used mains voltage rated X & Y capacitors + to earth - to earth & 270/290v VDR's + to - in 13 amp plugs with 1amp fuses, these are plugged into spare sockets on the trailing mains blocks. Living on top of a hill RFI/EMI is a problem, with roughly north mobile phone masts & Northolt air field, south Ealing Broadway every building has several communication aerials, east a plethora of mobile phone masts & to the west Heathrow, oh & the recent addition of 30'-40' away 2 car/mostly van charging points outside my top floor lounge window. |
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Post by palace on Feb 9, 2024 14:53:28 GMT
Serendipity struck today.
I changed the thin 6n OCC co-ax cables from record out on the pre-amp to record in on my cassette deck for a pair made from CT100 air core coax with the centre 1mm copper removed, there was a reduction in noise from the speakers but what was there pulsed?
I noticed that the earth wire from Hadcock GH 242 Silver plus tone arm on the turntable was wrapped around another lead, I disconnected it, as being thin would be easier to manoeuvre the moment it was disconnected from the Croft phono stage silence, the Croft was on, the arm on the rest so I turned volume up to full on the MC7R pre-amp, I had to put my ear virtually on the speaker to hear slight hum.
With the digital side the noise on full volume as before was non-existent.
Previously the GH 242 arm earthing/grounding to the Croft was essential to cut noise
I have had a deep think, the easy bit a ground/earth loop broken. Why suddenly? was there a ground loop, I can only speculate that after earthing the output sockets earth terminals of the Croft to the star earth point within the Croft it did not need the external earth.
What ever the case only a couple of cables to shield now but now no rush, I am enjoying from my Virgin Tivo box an ENO shortened Messiah at the moment the counter tenor Lestyn Davies is amazing as are the whole spectrum of the ENO performers.
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Post by palace on Feb 13, 2024 17:05:25 GMT
I have been listening to music played on the Hydraulic Reference turntable for a few days with not even one ear cocked for subtle system nuances, I found a misplaced very small round spirit level recently under a cable that I shielded.
Now the Hana ML has had plenty of time to run in & settle, I decided to check VTA & azimuth as well as tracking weight, I put it on the head-shell of the Hadcock GH 242 Silver Plus, I then set the Hana ML stylus in a grove of a non playing HI-FI News & Record Review, Test Record that Len Gregory gave me in the late 1990's soon after the record which he produced & voiced was released.
Using a thin mirror & the small level together with a BOM stylus grid/gauge I set the stylus as near 90deg. vertical as I could, without one of the electronic gauges available, however I did play band 5 side 2 of the test record, sound should be identical from each speaker, if switched to mono, another modification to my Croft phono stage by Mark Manwaring-White, the 2 channels + & - should self cancel, not quite but had to turn the volume up to hear anything.
Setting tracking weight on my Hydraulic Reference turntable is an interesting endeavour due to the 6 large gold platter weights on the plater surface, it involves a spacer on which sit the digital stylus gauge there is a small depression where the stylus/tracking weight is calculated, after 51 years of use initially with an SME gauge using digital Vernier gauge the depression on the digital scales is record surface height at the recommended 2 grams tracking force close to grove depth.
Then used the Test Record for bias setting unlike my previous Musicmaster Cartridge which needed very little the Hana ML required much more bias.
Another win win for me, the mids & treble are even more open with more air/ambiance fearing a loss of bass I put on Transformer, Perfect Day was beautiful & exquisitely romantic & gentle, with Walk On The Wild Side, Herbie Flowers bass intro was vibrant & deep, his double bass/bass guitar part threaded through the track like it's backbone; the coloured girls spread out as well as moving forward into the room the ending sax solo perfect.
I still have a couple of leads on a pair of LPSU'S to shield...
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Post by palace on Feb 18, 2024 15:43:02 GMT
My One Thing Audio Quad 57's have 3m TNT type cross connected coaxial UBYTE2 low inductance speaker cable. I did not know, that being cross connected at each end negates their screening properties.
I now know, not entirely shielded, though the UBYTE2 are coaxial the cross connection at each end apparently adds a variable, yesterday evening & today was spent sticking 20mm copper foil to 40mm thin stretch tape, to wrap around the twin twisted coax cables rather than stuck to the cables that would make reversal very difficult if the exercise was a retrograde step. but the overlapping copper foil acts as a faraday cage which works without grounding, so I did not earth it on either 3m lead. I then wrapped & insulated them with the thin stretch tape
There is now only a miniscule amount of hum ear to speaker on Croft phono stage & full volume. The TV picture is a little sharper as is the PC monitor. The turntable with Hadcock GH242 Silver + with Hana ML sounding better than ever bass deeper with no overhang except the lovely bloom of a double bass or natural decay of a big drum whether pop or classical, mids & treble voices male or female incisive but emotive as in listening to Anna Moffo singing Songs Auvergne by Canteloube or Stevie Wonder Talking Book or Lou Reed Perfect Day/Walk on the Wild Side not sharp or harsh more of a feel of the ambiance, I'm minded of Goldilocks & the 3 bears "just right".
The digital side is all of the above and totally silent with pause & full volume I just listened to Nights in White Satin, Justin Hayward never had so much emotion in his voice here neither has Carly Simon from the video of Moonlight Serenade Live on the QE2.
There is one 4 gang distribution board cable left to shield it has 2 linear PSU'S & the mains power to the neon bulb which runs at UK mains 50hz for the strobe disc of Hydraulic Reference which no longer has a AC motor since I fitted a Maxon. DC one.
Addendum
I have noticed this afternoon not before, even the Sony TV speaker sound has improved although the system i.e. the DAC & amps are switched off. I'm amazed.
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Post by palace on Feb 19, 2024 15:21:15 GMT
Yesterday I wrote "I have noticed to my amazement this afternoon with the system switched off even the sound of the TV speakers has improved"...
Just a quick update, later on yesterday after switching off the DAC, pre-amp & power amp watching/listening to my Sony TV fed by a Virgin HD Tivo box with just the TV speakers working, I realised that the sound from the TV had improved in that it had some actual bass & was generally sweeter, voices sounding less mechanical, the same is true today; a very unexpected result & yes the picture on the TV & Wi-Fi driven PC monitor also sharper. I'm still processing this...
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Post by MikeMusic on Feb 19, 2024 16:46:03 GMT
The madness of tweaking and having unexpected bonuses !
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Post by palace on Feb 24, 2024 13:16:29 GMT
The madness of tweaking and having unexpected bonuses ! It so does, Yesterday I made a cardboard screen covered in copper foil then covered with thin plastic, slightly deeper & wider abutting the steel trays used on the bottom & sides to screen the Croft phono stage slipped close behind it with short wings wrapping around the the sides slipping behind the steel trays, with slits/flaps in the cardboard screen for the IEC power cable & the vertical + - in & vertical + - out phono cables all of which are also copper foil covered & insulated. This move/mod has had an apparently disproportionately positive result one of the biggest individual ones, whether it has screened the 4 un-screened leads at the rear from the Croft transformer or more likely screened the SUT's in the Croft from stray EMI/RFI 50hz fields, in truth I don't know. However the 50hz hum is virtually inaudible as it's damp weather it could even be noise from the OTA Quad 57's, it happens sometimes with high humidity; As before there has been another improvement in the TV & Wi-Fi derived PC monitor pictures as well |
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Post by MikeMusic on Feb 24, 2024 16:24:55 GMT
Keep at it !
There's all sorts to come from what you are doing
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Post by palace on Mar 1, 2024 21:37:54 GMT
Keep at it ! There's all sorts to come from what you are doing You are so correct, I have made a cardboard sheet covered in foil, a tad wider & higher than the rear of the Croft phono stage with 3 flaps for the in & out phono leads together with one for the IEC plug & power lead, with ears extending around the sides of the case which are unperforated unlike the bottom & top, though there is a strip 3" wide at the rear now also covered in cardboard. Yet another improvement in audio & TV picture as well as the monitor on my PC were I can now see clearly individual design markings on 1/8" high short cut icons. Obviously the turntable LP side is now better than it ever has been; what I can not explain is why has the digital side also improved like the TV picture & sound from the built in speakers of the TV, then even with the croft switched off, with the system on today I was playing the DVD of Brian Wilson & Friends incredible ambiance voices exceptional & forceful bass, with a TV production from 1983 of G & S Mikado DVD with William Conrad as the Mikado & The genius who at 91 is still Clive Revell as Ko-Ko, There are several scenes where 3 singers of various mixtures of men & women sing 3 different lines the voice separation & clarity was incredible as are the extraneous noises from this stage production from feet & stiff Japanese clothing rather like when at a ballet the thumps as a ballet dancer lands though not so loud. I have owned the DVD for years & proved to be a revelation today even the visuals. Floyd The Endless River DVD sounded great. I also found that set by ear & not looking at the dial I had set the volume knob between 9 & 10 o'clock rather than the previously usual 12 o'clock. Any suggestions as to why would be welcomed... |
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Post by MikeMusic on Mar 2, 2024 16:00:44 GMT
Why ?
A general thought
Everything is connected to everything - in some way or another
Improvements here may well change 'over there'
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Post by palace on Mar 3, 2024 13:33:22 GMT
Why ? A general thought Everything is connected to everything - in some way or another Improvements here may well change 'over there' MikeMusic you are absolutely correct regarding the analogue helping the digital & probably vice versa with shielding & clip on ferrites on the digital side. Having had time to ponder possibilities about the volume control adjustment. 1) I do not think that with less interfering electrical hash/EMI & 50hz hum etc allows the input & output transformers of the power amplifier to amplify with more vigour the audible music portion of the signal, because there is less ectopic signal to cause power sapping "vibration" & heat or if it does it can only part of the answer. Though although the Rogue Atlas Magnum EI Transformers were never audible unlike some toroidal transformers can be when subjected to DC offset on dirty mains power lines, neither did they run hot only warm though they do seem to run very slightly cooler to the touch now. 2) It occurs to me that my ageing ears no longer need the higher volume to hear the subtle nuances in music because without the interference of electrical hash/EMI & 50hz hum etc now the speaker output being so much cleaner & better defined, I probably now use what is comfortable though probably only 2 or 3 db less rather than what was previously necessary for me. 3) As with the analogue helping the digital I'm open to it being a bit of both... |
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Post by MikeMusic on Mar 3, 2024 15:25:57 GMT
I have examples in the main and kitchen system
They keep getting better
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Post by palace on Mar 12, 2024 21:08:02 GMT
2 or 3 days ago I was reading about a Tisbury Audio Domino passive phono stage, I looked up the user manual as the old 2018 article I read suggested that TA were going to produce a quality LPSU could not find that, however I read.
Low pitched hum: Make sure your turntable’s ground
lead is connected to the Domino’s ground post. Try
plugging turntable or amp into different sockets.
Interference:
Make sure your turntable’s ground lead is
connected to the Domino’s ground post. Use high
quality shielded interconnects. Attach a ferrite core to
the ground lead near Domino’s ground post.
Now I had cogitated if slipping a ferrite on to the turntable drain/ground lead on my modified for Hana ML moving coil Croft phono stage would be worthwhile, I had decided no as it carried no current as such & as a single wire had no return.
Having read the above from Tisbury Audio a respected manufacturer. I made several wraps around a 1" id ferrite ring + a small clip on ferrite each side akin to the Throttle Internet cable.
Another improvement to analogue as expected very low 50hz hum now. Also the by now anticipated digital improvement including the sharper with even more detail TV picture & WiFi driven PC monitor. May be applicable to DAC's or other equipment with grounding screws.
I now realise as with all the other screened leads (prior to screening them that is)ie Ethernet, phono & power that had acted as aerials for the vast amount of RFI/EMI 50hz hum I suffer
Another success thanks to a constant willingness to borrow(plagiarise) the work ideas of others as well as evolve my own thoughts.
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Post by palace on Mar 16, 2024 14:01:04 GMT
At the beginning of my attempts to eliminate noise from the Croft phono stage after Mark Manwaring-White fitted a pair of SUT's in the Croft, to reduce noise I decided to wire the 2 earth tags from the output phono sockets to the main/central star tag earthing point using a single pair of twisted CAT 6 wires one side to each tag. This was prior to my exploits with copper foil shielding.
Last night, in a dream I removed them with a very positive result. I have learned over the last nearly 75 years to trust my subconscious that occasionally rationalises & collates whilst sleeping my cluttered disparate waking thoughts in cohesive dreams that unusually I remember on waking.
This morning I cut the earthing wires wires off.
Eureka when the arm is on the rest & full volume on the pre-amp the hum is now almost absent, nearly on par with the total silence when the Digital side is switched in. The result on playing a record is a slight change of timbre on replay, this has also resolved in to a wider soundstage more articulate bass mid range & treble has a similar positive effect.
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