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Post by brucew268 on Sept 14, 2023 18:52:47 GMT
Since others have gone down this path, I thought I might venture a little bit. My real desire is to find file-based playback that is not only technically superior on several measures but also has great musical flow, natural tonality, and strong image depth that gives the sense of people playing instruments in 3D space. In the meantime I opened the 6000CDT and took several photos and catalogued what I was seeing. - There are three sets of AC wires in order to handle both 110V and 230V, but none had a significant twist to them and had some gaps, so I put a proper twist to each.
- A number of people have used sound dampening sheets, but in my experience they must be used judiciously or they rob the harmonics and shift or establish a frequency focus to the music. That should be less of an issue with an all digital component, but it sure has been an issue on ethernet devices, so.... I put several SilentCoat strips on the CD mechanism and left the chassis alone, just to be safe.
- The smoothing caps strangely enough are general purpose ones without significant ripple or impedance ratings. The first is a Panasonic NHG 2200uF 25V and the second is a Panasonic M 4700uF 16V. Replacing these with ones having much better ripple and impedance ratings may help.
- There does not seem to be anything like an output cap.
- The main power supply has three LM317 regulators with two caps on each and there are two other sections with LDO 3.3V regulators.
- The main bridge rectifiers mkight do with upgrading with a Schottky bridge. Though that specific through hole format is not stocked by anyone, I could use an SMD in a 4LPDIP format which would line up with the pads correctly. CBRLDSH2-40 or CBRLDSH2-100 should do, the latter having astonishingly low leakage rate.
- The clock is a proper TCXO, hence the solid sense of natural flow. I wonder what some ERS fabric will do on it, the Differential Line Driver, and the Signal transformer.
- I wonder if there is a BNC connector that could be a drop in replacement for the RCA SPDIF jack?
 20230914_125650 by BruceW, on Flickr Added twist to AC wire looms.  20230914_130916 by BruceW, on Flickr SilentCoat on CD mechanism  20230914_115358 by Bruce W, on Flickr - The twists on the AC wires gave no detectable effect on the sound.
- The SilentCoat on the CD mechanism gave little effect on the sound but did give an ever so slightly blunt forcefulness to the presentation which was not positive.
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Bigman80
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Post by Bigman80 on Sept 14, 2023 20:09:54 GMT
I'd definitely change those regs.
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Post by firebottle on Sept 15, 2023 6:32:34 GMT
I would also remove the standby smps. You would lose the standby function.
Easy enough, remove D1,D2,D3,D4 and short across the contacts of the power relay.
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optical
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Post by optical on Sept 15, 2023 6:46:03 GMT
I would also remove the standby smps. You would lose the standby function. Easy enough, remove D1,D2,D3,D4 and short across the contacts of the power relay. Love these sort of suggestions đź‘Ť |
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Post by brucew268 on Sept 15, 2023 7:41:17 GMT
I would also remove the standby smps. You would lose the standby function. Easy enough, remove D1,D2,D3,D4 and short across the contacts of the power relay. On one hand it would be great to do that and remove an SMPS. Interestingly, when I tenporarily added another SMPS (non-audiophile) on the same distribution block feeding something else like the DAC or streamer, it seemed to make the 6000CDT sound terrible. It wasn't until I unplugged the SMPS that the 6000CDT sounded right again. I could only assume it's SMPS did not play well with others.
On the other hand, when powering on from the back switch the 6000CDT takes 10-15 minutes to "warm up" and sound right. But powering on from Standby, it sounds right immediately. So removing the standby function does have real world consequences.
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Post by zleepy on Sept 15, 2023 8:03:10 GMT
I have this transport as well, and I bought an upgrade kit for it from Hoer Wege. It consisted of damping material, A whole bunch of Panasonics FM caps, some film caps for bypass duty, quality diodes to replace the cheap bridge rectifiers, and an AES out mod.
The AES output mod I like very much, it is robbed from the coax out and does not improve the sq, but it gives the transport more flexibility for me.
To my ears the modifications brought improvements. It was very good stock, and even better after the mods.
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Post by brucew268 on Sept 15, 2023 10:58:40 GMT
I would also remove the standby smps. You would lose the standby function. Easy enough, remove D1,D2,D3,D4 and short across the contacts of the power relay. It looks like I could just as easily go straight from the IEC inlet to the transformer and just ignore all the standby circuitry. The black and white are the primaries for 230+VAC, so could attach those directly to the IEC inlet. Of course that would make it harder to "undo" if I cut off the molex crimps. Maybe attach header pins to the IEC tabs and then plug into that from the transformer primaries. It would at least test whether there was an improvement to the sound. I have this transport as well, and I bought an upgrade kit for it from Hoer Wege. It consisted of damping material, A whole bunch of Panasonics FM caps, some film caps for bypass duty, quality diodes to replace the cheap bridge rectifiers, and an AES out mod. The AES output mod I like very much, it is robbed from the coax out and does not improve the sq, but it gives the transport more flexibility for me. To my ears the modifications brought improvements. It was very good stock, and even better after the mods. Interesting website, looks like a good source on the continent. Except for the XLR conversion, which I could find no mention of on the website, the other mods look like the basic PSU upgrades I'm considering. |
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Post by firebottle on Sept 15, 2023 11:32:01 GMT
Easy enough, remove D1,D2,D3,D4 and short across the contacts of the power relay. It looks like I could just as easily go straight from the IEC inlet to the transformer and just ignore all the standby circuitry. The black and white are the primaries for 230+VAC, so could attach those directly to the IEC inlet. Of course that would make it harder to "undo" if I cut off the molex crimps. Maybe attach header pins to the IEC tabs and then plug into that from the transformer primaries. It would at least test whether there was an improvement to the sound.Excellent plan. |
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Post by brucew268 on Sept 16, 2023 15:09:16 GMT
Last evening I threw on some old Shawn Colvin doing covers by writers she admires and a couple songs in it occurred to me that her voice and instruments were not emerging from the quiet background that I usually hear on the album. It seemed that everything was just a bit grey. The only change I made this week was to twist the AC wires more in the CD transport. Could that be affecting this? I then recalled Chris’s experience with an Audio Note DAC where he “cleaned up” a rats nest of wires only to find that the sound suffered and had to be returned to original. I opened the CD transport and relaxed the twists significantly. The original state had just one twist in about 6 inches and some gaps between wires, so I put things maybe halfway back to that. Back together and hit play. Bingo, the background went quiet, the voices and instruments were much clearer and dynamic! If I’d spent hours soldering upgraded parts in and got this result, I’d have a big smile. So maybe enjoy this a bit. Of the pics below, which would you think would sound better and why? I’m not sure why this is better than the higher, tighter twist. 20230914_125650 by BruceW, on Flickr  2023-09-16_02-15-07 by BruceW, on Flickr |
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Bigman80
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Post by Bigman80 on Sept 16, 2023 16:36:21 GMT
Last evening I threw on some old Shawn Colvin doing covers by writers she admires and a couple songs in it occurred to me that her voice and instruments were not emerging from the quiet background that I usually hear on the album. It seemed that everything was just a bit grey. The only change I made this week was to twist the AC wires more in the CD transport. Could that be affecting this? I then recalled Chris’s experience with an Audio Note DAC where he “cleaned up” a rats nest of wires only to find that the sound suffered and had to be returned to original. I opened the CD transport and relaxed the twists significantly. The original state had just one twist in about 6 inches and some gaps between wires, so I put things maybe halfway back to that. Back together and hit play. Bingo, the background went quiet, the voices and instruments were much clearer and dynamic! If I’d spent hours soldering upgraded parts in and got this result, I’d have a big smile. So maybe enjoy this a bit. Of the pics below, which would you think would sound better and why? I’m not sure why this is better than the higher, tighter twist. 20230914_125650 by BruceW, on Flickr 2023-09-16_02-15-07 by BruceW, on Flickr I suspect it was probably due to going from a white cable fixing, to a black one. It's the only explanation lol |
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Post by firebottle on Sept 17, 2023 6:18:54 GMT
Twisting tightly will add capacitance between each wire, though I wouldn't have thought enough to make any difference.
Live and learn eh?
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Post by brucew268 on Sept 26, 2023 21:00:50 GMT
Based on the discussion in another thread, the last two days I’ve turned on the CD transport and DAC 5-8 hours before listening instead of 10 minutes before. The result was a different listening experience. It made a significant change to the amount of body in the music and also affected the sense of pace. But now the body in the mids was a bit too much and losing a touch of clarity in the top end. In staring at the transport considering this, I noticed the anti-RFI fabric sheet under the transport that’s been there for much of the last year and started experimenting with it. Removing the RFI sheet pushed the focus back towards HF and got a bit too busy. Back in place, where it was under the transport made an audible difference to the sound. At the back of the transport is one circuit board*. Then the transport mechanism itself also has a circuit board mounted to its underside, and the front panel has circuits related to the display and control buttons. It turns out that the sound benefits most from the RFI sheet under the front panel only. So, no A4 sheet but more like a 80mm x 160mm piece. Having two different makes of RFI shielding fabric, one did too little and the other sharpened things enough that there was a slight sense of something like overhang on the transients. Remembering that the remote allows the display to be turned off altogether, I tried that and found it had a subtle but desired effect on backing off the hint of crispiness from the transients to be more natural. Subtle enough that I’d be happy listening with the display on a lot of the time, but for some sessions will appreciate the extra sonic benefit of turning it off. It might take a couple more days of listening before I feel confident enough about the sonic signature to start modding the PSU.
*PSU, clock, connection circuits, standby circuit, etc
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Bigman80
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Post by Bigman80 on Sept 27, 2023 9:37:18 GMT
I assumed that everyone left digital on 24/7 like i do?
I am glad to read that there was an audible effect on start up time.
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Post by lurch on Sept 27, 2023 11:02:28 GMT
I assumed that everyone left digital on 24/7 like i do? I do for all SS elements, Innuos, switches, Uptone usb regen, in System 1 + Wiim Pro, DacMagic Plus & Caimen SEG in System 2/2a. The BI being valve output I switch off, especially as it's running with TFK 83s and they is pricey now, though do have a spare pair. |
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Post by brucew268 on Sept 27, 2023 11:52:39 GMT
I assumed that everyone left digital on 24/7 like i do? I am glad to read that there was an audible effect on start up time. I switched [!] last year when one LPSU started going south and would be come unstable after a few hours, with audible effects. With that fixed now, I suppose I could return to 24/7 or at least powering on each morning. Even though the idle draw of the 686 is pretty low as SS, with the utility prices of the last year it seemed more responsible to switch it off when not in use. |
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Bigman80
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Post by Bigman80 on Sept 27, 2023 12:00:48 GMT
I assumed that everyone left digital on 24/7 like i do? I am glad to read that there was an audible effect on start up time. I switched [!] last year when one LPSU started going south and would be come unstable after a few hours, with audible effects. With that fixed now, I suppose I could return to 24/7 or at least powering on each morning. Even though the idle draw of the 686 is pretty low as SS, with the utility prices of the last year it seemed more responsible to switch it off when not in use. I think the entirety of my hifi (in use) costs about 5p an hour? The 686 and BT2 only come on when I listen to the system. The DAC/Mutec and X50D is always on at around 1p an hour when I am not listening. |
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Post by pete on Sept 27, 2023 13:17:29 GMT
I switched [!] last year when one LPSU started going south and would be come unstable after a few hours, with audible effects. With that fixed now, I suppose I could return to 24/7 or at least powering on each morning. Even though the idle draw of the 686 is pretty low as SS, with the utility prices of the last year it seemed more responsible to switch it off when not in use. I think the entirety of my hifi (in use) costs about 5p an hour? The 686 and BT2 only come on when I listen to the system. The DAC/Mutec and X50D is always on at around 1p an hour when I am not listening. 5p and hour works out to be about 170 Watts, so that sounds about right compared to mine. 1p an hour, So that is about ÂŁ90 a year which is about 300 KW/h or 54Kg of CO2, just putting the figures out there. I don't leave my system on 24/7, I guess that I probably don't listen to it as much as some folks on here.. 300KW/h would be about the same as 20% of my current electricity usage for everything in my house. |
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Bigman80
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Post by Bigman80 on Sept 27, 2023 13:50:16 GMT
Well, considering a single Big Mac is to blame for 2.35kg of CO2e, and on average more than 2.4 million are sold daily in the UK.....I'm not going to worry too much about the HiFi 🤣
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optical
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Post by optical on Sept 27, 2023 14:01:27 GMT
Well, considering a single Big Mac is to blame for 2.35kg of CO2e, and on average of more than 2.4 million sold daily in the UK.....I'm not going to worry too much about the HiFi 🤣 That's why I tend to order 3 Big Mac's at a time to help save the planet, I'm very conscientious like that. |
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Bigman80
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Post by Bigman80 on Sept 27, 2023 14:03:06 GMT
Well, considering a single Big Mac is to blame for 2.35kg of CO2e, and on average of more than 2.4 million sold daily in the UK.....I'm not going to worry too much about the HiFi 🤣 That's why I tend to order 3 Big Mac's at a time to help save the planet, I'm very conscientious like that. I don't want to detail Bruces thread, so I will shift all of this onto a new one in the "off topic" section when I get home from the school run. |
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Post by pete on Sept 27, 2023 14:35:20 GMT
Well, considering a single Big Mac is to blame for 2.35kg of CO2e, and on average more than 2.4 million are sold daily in the UK.....I'm not going to worry too much about the HiFi 🤣 Yep, and as we decarbonise and the grid it would become less of an issue, but those Big Macs…. I’ve never had one, so can’t see the attraction. |
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Bigman80
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Post by Bigman80 on Sept 27, 2023 15:49:38 GMT
Well, considering a single Big Mac is to blame for 2.35kg of CO2e, and on average more than 2.4 million are sold daily in the UK.....I'm not going to worry too much about the HiFi 🤣 Yep, and as we decarbonise and the grid it would become less of an issue, but those Big Macs…. I’ve never had one, so can’t see the attraction. They're nothing to to write home about....more carbon than they're worth. |
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Post by brucew268 on Sept 29, 2023 17:18:35 GMT
I’m coming to the conclusion that the RFI absorption fabric under the transport (26/9/23) is not behaving equally across the frequency spectrum. If I understand it, the fabric is meant to remove background noise so that the details stand out with better definition/contrast if used judiciously in the right place. But now it feels more like it just adds a bit of sharpness to the HF details rather than lowering the noise floor, helpful on some recordings but not on others. So I pulled it all. The result without any RFI fabric is slightly more natural though the noise floor is not as low as I remember it a few weeks ago. What might have changed in the last few weeks to affect that?
Em, the only change I can thnink of is a linear PSU connected to a digital component but it is *powered off*. So with no power, the only physical connection to the HiFi is the mains lead and it is switched off so only the earth wire is common to the HiFi. Right, unplugged it and the noise floor just dropped a bit so that the music definition naturally comes through a little better.
This doesn’t make sense to me that a powered off component with a linear power supply to boot would have an effect on the noise floor of the HiFi. But I’m appreciating the purity of the music more now.
Tomorrow, I try to bypass the 6000CDT’s Standby circuit with what seems to be its own little SMPS PSU, and see if we get further on noise floor and SQ naturalness.
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Post by brucew268 on Oct 2, 2023 11:04:36 GMT
Well that didn’t work, but good result anyway!
I tried two approaches to bypassing the SMPS and switch relay for the Standby circuit, and the Standby circuit and continued to work! After a closer look, the SMPS that powers the switch is actually set to lose power when the switch is turned on, which must mean that it then transfers power to the 3.3v LPS circuit.
That’s a clever design as it means the SMPS only operates when the 6000CDT is off so that it does not affect the SQ when the 6000CDT is running.
I do wonder whether the digital circuits would benefit from some RFI shielding fabric around the inductors as long as the conductive fabric is shielded from actual contact? One inductor is for the SMPS and the other has the mains always running through it.
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Post by brucew268 on Jan 18, 2024 15:53:08 GMT
A bit of an update: In November I changed the bridge rectifiers to Schottky and the main smoothing caps in the power supply to Panasonic FR, with a good result.
I was trying to push the noise floor ever lower, so changed again to soft recovery ultra fast diodes (non-Schottky). That didn’t do it, was better with the Schottky.
I also changed the voltage regulators for ones that have better specs and changed out all the caps on the main board for Panasonic FR. Didn’t really have better perceived effect. In fact, bass depth and articulation seemed better with the stock “rubbish” caps.
After plumbing in the Muse Model Two DAC I decided that at this point, which is rather good by the way, further gains on the 6000CDT would be dearly bought. The Muse DAC was renowned for its ultraquiet power supply and DAC circuitry and I could hear that difference between it and the Calyx DAC which has a rather good external LPSU.
** A couple 6000CDT DIY notes: The bottom surface of the Audiolab circuit board is very thin, practically painted on. So using Mr SolderFix’s multipin desoldering trick can easily burn right through the bottom layer unless you are quick and with the right amount of heat.
The Audiolab CD transport has a huge ground plane, which makes many of the “neg” holes difficult to clear even with good techniques. After changing the bridge rectifiers 3x, the board had enough and separated a bit in that area. Oops. Thankfully Audiolab has been kind enough to order a replacement main board for me, so waiting for that.
In the end, I think that changing the bridge rectifier to Schottky and the two smoothing caps to better spec produce the best result which is an amazing feat for a CD transport at that pricepoint. Any further changes may or may not have any good effect. |
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