Andrew,
Are the the seperate toroids switched like the standard toroid or have they continuously voltage?
I have a philips cd 710 (with tda1545A) and i want to put 2 toroids for the dac and a new low jitter clock.
The switch is only for the secondary side 10v ac and not for the primary side.
Matthijs
Are the the seperate toroids switched like the standard toroid or have they continuously voltage?
I have a philips cd 710 (with tda1545A) and i want to put 2 toroids for the dac and a new low jitter clock.
The switch is only for the secondary side 10v ac and not for the primary side.
Matthijs
Wel my testbed CD48 has arrived and seems to be in perfect working order. Out of the box, I'd say it sounds ok. Inoffensive springs to mind. Not very special anywhere and not terrible at anything. It shows its limitations when you turn up the volume. It gets a bit confused with complex orchestral works and is generally a bit thin in the bass - no weight, no airiness. It images quite well though. Lets get to work and see what we can do!
Fantastic !
Looking forward to your early results - the gains arrive very quickly in every area you mention.
Hope you like what happens !!!
My 100 VA traff is finally here plus a nice 22,000uf RIFA smoother.
They'll be prepped tomorrow and in by Saturday at the latest.
If there's a nice enough step I'll repeat it for all the dac chip receivers.
Clock is coming and then it'll be finished - sort of.
What I REALLY want to do is remove the whole of transport plastics and mount the green board plus traffs into a copper clad hardwood case and have it as a suspended top loader.
I've now found and worked out the switch wiring to read the disc and I can use the remote control and display for functions.
I'm going to do it too.... and it could be soon
They'll be prepped tomorrow and in by Saturday at the latest.
If there's a nice enough step I'll repeat it for all the dac chip receivers.
Clock is coming and then it'll be finished - sort of.
What I REALLY want to do is remove the whole of transport plastics and mount the green board plus traffs into a copper clad hardwood case and have it as a suspended top loader.
I've now found and worked out the switch wiring to read the disc and I can use the remote control and display for functions.
I'm going to do it too.... and it could be soon
Bloody hell - seriously hard acts to follow I suspect !!
erm....well now I've got my fingers crossed !!
Mine is no longer displaying any of the traits you mention and your assessment incidentally was spot on of the 48 in standard trim.
That said, the dac out trick is hugely rewarding as is removing the op amp.
PS caps reward with a massive step in the bass and then the rest polish everything up nicely.
Adding traffs, extra uf and regulators provide quieter backgrounds, speed and grunt.
It may not steal top spot in your system but it'll not disgrace itself either. The signal will certainly have a shorter and cleaner route to the rca sockets and that's exactly what you want. Fewer influencing and polluting rubbish bits in the way.
I've done the op amp changing futility for years and nothing sounds like having none .
I had an MCD pro Meridian years ago, then a 206, 208 and 506 from same, a borrowed Krell player ( which was astonishing btw ) and a substantially modded 6 traff Arcam Alpha.
My 48 is now as satisfying as everything I've had in my system over the years and the best thing of all is that I did it myself....after a few crashes along the way.
100VA transformer now powering the digital and analogue stages of the dac chip and the old 35VA powering the op amps.
The changes are NOT subtle and I'm ordering 2 more 100VA's - 1 for dac chip internal i/v op amps and the other for separating the dac chip stages.
The weight and depth of bass and drum impacts is just exhilarating as it is - like nothing I've had in my system - period.
God knows how it'll sound with the 3 new traff's working together and the independently powered clock ...
Pics later
The changes are NOT subtle and I'm ordering 2 more 100VA's - 1 for dac chip internal i/v op amps and the other for separating the dac chip stages.
The weight and depth of bass and drum impacts is just exhilarating as it is - like nothing I've had in my system - period.
God knows how it'll sound with the 3 new traff's working together and the independently powered clock ...
Pics later
if your going straight from tda chip to output, I would consider trying a couple of these as output buffers, they sound good and give the output a bit of drive capability:
Diamond Buffer Board Stereo Broadband Strong Driving Capability Assembled | eBay
Diamond Buffer Board Stereo Broadband Strong Driving Capability Assembled | eBay
Do it....you're going to be astonished.
You're existing CD replay eqt is pretty much ' up there ' with the very best ( a guess of course ) but I've a feeling you will be impressed by this.
I can't believe what it's doing already and I'm only 3 or 4 more surgeries away from completion.
It just sounds like it's idling along now.
I have absolutely no idea why this tiny, cheap and basic dac chip has responded so positively to almost every single thing I've done.
I've added almost brutal levels of reserve tx power, regulation and capacitance and all it's done is respond proportionately...all that's left to do is apply 2 more tx's and a clock.
I simply can't wait to hear it maxed out and that's about £60....ish ( hello ? )
Also my idea of re - casing and making it a top loader has stemmed from the lack of space for additional bits inside the existing case.
It may also bring with it some improvements in sound q.
I'm going to give it a shot too - and I'll share the results if it works
You're existing CD replay eqt is pretty much ' up there ' with the very best ( a guess of course ) but I've a feeling you will be impressed by this.
I can't believe what it's doing already and I'm only 3 or 4 more surgeries away from completion.
It just sounds like it's idling along now.
I have absolutely no idea why this tiny, cheap and basic dac chip has responded so positively to almost every single thing I've done.
I've added almost brutal levels of reserve tx power, regulation and capacitance and all it's done is respond proportionately...all that's left to do is apply 2 more tx's and a clock.
I simply can't wait to hear it maxed out and that's about £60....ish ( hello ? )
Also my idea of re - casing and making it a top loader has stemmed from the lack of space for additional bits inside the existing case.
It may also bring with it some improvements in sound q.
I'm going to give it a shot too - and I'll share the results if it works
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Hi Andrew, its tempting to join you in modding one of these players. I have modded a few players now and I find its best to go slow. The amount of capacitance and decoupling cap size can really change the sound, and sometimes its a balancing act between bass and the rest IMO.
Your bitumen pads gave me a surprising improvement. I also got a pack of blutack and filled in all the plastic gaps I could find on the transport, this is really good mod. you can add a lot of mass to the transports and it helps.
There is no limits, and if you look around you can use pass transistor, tl431 shun and tl431 with shunt element really close to the chip instead of three pin. I only did this with the output stage analog on one player, but its a nice change. Some of these simple power supplies can sound very good. Check out this thread, most of these can be made on varo board close to the pins:
Simple Voltage Regulators Part 1: Noise - [English]
CD mod threads are my favorite for some reason so even though people aren't replying, we are eagerly watching and awaiting your updates
Nowadays I only use digital so I don't really need a cd player, in fact I sold all four I had and bought an Audiolab 8200CDQ which means I get a usb dac and cd player for the wife who doesn't use it anyway
Good luck with your upgrades and keep us posted.
Your bitumen pads gave me a surprising improvement. I also got a pack of blutack and filled in all the plastic gaps I could find on the transport, this is really good mod. you can add a lot of mass to the transports and it helps.
There is no limits, and if you look around you can use pass transistor, tl431 shun and tl431 with shunt element really close to the chip instead of three pin. I only did this with the output stage analog on one player, but its a nice change. Some of these simple power supplies can sound very good. Check out this thread, most of these can be made on varo board close to the pins:
Simple Voltage Regulators Part 1: Noise - [English]
CD mod threads are my favorite for some reason so even though people aren't replying, we are eagerly watching and awaiting your updates
Nowadays I only use digital so I don't really need a cd player, in fact I sold all four I had and bought an Audiolab 8200CDQ which means I get a usb dac and cd player for the wife who doesn't use it anyway
Good luck with your upgrades and keep us posted.
Hi Luke
I can tell you that you're proposed exercise is wholly unnecessary in the context of the CD48 due to there being no drop in output volume following the o/s bypass conversion and with zero effect on sheer drive and transparency.
This whole exercise has revolved around minimising ' rubbish ' in the signal path and not adding to it .
Not suggesting the unit is rubbish of course.....
Have you bought this item off ebay already, which machine did you apply it to and how did it improve the overall sound ?
Do let us know
Thanks
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Hi Andrew, I have not used this, but I like the sound of diamond buffers. Sometimes a buffer does more good than harm, it depends on your system I guess. If you have a high impedance amp or preamp you may not get any benefits.
Hi Andrew, its tempting to join you in modding one of these players. I have modded a few players now and I find its best to go slow. The amount of capacitance and decoupling cap size can really change the sound, and sometimes its a balancing act between bass and the rest IMO.
Your bitumen pads gave me a surprising improvement. I also got a pack of blutack and filled in all the plastic gaps I could find on the transport, this is really good mod. you can add a lot of mass to the transports and it helps.
There is no limits, and if you look around you can use pass transistor, tl431 shun and tl431 with shunt element really close to the chip instead of three pin. I only did this with the output stage analog on one player, but its a nice change. Some of these simple power supplies can sound very good. Check out this thread, most of these can be made on varo board close to the pins:
Simple Voltage Regulators Part 1: Noise - [English]
CD mod threads are my favorite for some reason so even though people aren't replying, we are eagerly watching and awaiting your updates
Nowadays I only use digital so I don't really need a cd player, in fact I sold all four I had and bought an Audiolab 8200CDQ which means I get a usb dac and cd player for the wife who doesn't use it anyway
Good luck with your upgrades and keep us posted.
Have you seen the low noise regulators in my posts and pics ?
They're super low noise audio-gd ' class a ' items ( whatever that means ) and I have a slab of 20mm mdf glued to the base of the player.
It's fairly inert now and I assume not really resonating anywhere.
The 3 pin ' drop in ' super regulator replacement items have always seemed a total ' rip off ' to me considering the component count
and if I could make them myself I'd sell them for £15..... hahaha
On my system, I have a 6N6P valve buffer that takes the signal from the CD and fires it into a Goldpoint mini V attenuator before the power amps. 6 of them actually.
It all works OK and is simple in it's implementation
What about you ?
Just fyi :
My speakers were hand made ( by an ex studio engineer ) on an extremely remote Scottish Island.
They are made from 15mm solid slate ( yes, black stone from the ground ) and 35 mm beech - and that's a tree btw.
They have 4 vintage drive units each, 6 of which have Alnico magnets and are driven by 6 monobloc power amps - LM3886 GC's
My interconnects are all short pure silver, 8TC Russ Andrews speaker cables ( bank loan ) and I even filled the sub floor void in my listening room with liquid concrete ( where my speakers would sit ) to eliminate sub floor BOOM.
Mains is fed from a dedicated spur from my mains supply inlet and I'm about to drive a 4 foot copper spike into the garden as an earth.
....and you want me to insert a buffer, that you never heard or used into my own system ? .....( totally laughing out loud now )
Then you suggest blue tak and bitumen.......
No offence.....just please don't assume I use Technics, Denon, Yamaha, Sony, Matsui or mass produced stack systems.
I worked in a seriously high end audio retailer for six years where I sold Levinson, Krell, Pierre Lurne, Naim Audio and several other high end brands.
It used to take us nearly an hour to unpack Wilson Watts Puppies - try ' Google ' if you don't know what I'm talking about
My ears are pretty much ' on it ' and I play a musical instrument very proficiently too ( unlike 99% of the electronics engineering experts on this bloody site )-
Y'know...suggesting I try a buffer that you have no knowledge nor experience of, recommending taking my time and then telling me to try ' blue tak and bitumen ' is a bit patronising imho.
QUOTE : ' I would consider trying a couple of these as output buffers, they sound good and give the output a bit of drive capability '
Hunt out venerable member ' AndrewT ' and suggest it - let me know what he says please.
Good luck with your projects
My speakers were hand made ( by an ex studio engineer ) on an extremely remote Scottish Island.
They are made from 15mm solid slate ( yes, black stone from the ground ) and 35 mm beech - and that's a tree btw.
They have 4 vintage drive units each, 6 of which have Alnico magnets and are driven by 6 monobloc power amps - LM3886 GC's
My interconnects are all short pure silver, 8TC Russ Andrews speaker cables ( bank loan ) and I even filled the sub floor void in my listening room with liquid concrete ( where my speakers would sit ) to eliminate sub floor BOOM.
Mains is fed from a dedicated spur from my mains supply inlet and I'm about to drive a 4 foot copper spike into the garden as an earth.
....and you want me to insert a buffer, that you never heard or used into my own system ? .....( totally laughing out loud now )
Then you suggest blue tak and bitumen.......
No offence.....just please don't assume I use Technics, Denon, Yamaha, Sony, Matsui or mass produced stack systems.
I worked in a seriously high end audio retailer for six years where I sold Levinson, Krell, Pierre Lurne, Naim Audio and several other high end brands.
It used to take us nearly an hour to unpack Wilson Watts Puppies - try ' Google ' if you don't know what I'm talking about
My ears are pretty much ' on it ' and I play a musical instrument very proficiently too ( unlike 99% of the electronics engineering experts on this bloody site )
-Y'know...suggesting I try a buffer that you have no knowledge nor experience of, recommending taking my time and then telling me to try ' blue tak and bitumen ' is a bit patronising imho.
QUOTE : ' I would consider trying a couple of these as output buffers, they sound good and give the output a bit of drive capability '
Hunt out venerable member ' AndrewT ' and suggest it - let me know what he says please.
Good luck with your projects
Finally, a chopped spare display I had lying around.
This way it's remote control only..
I'll stick with the top loading now it's reliable - less clanking plastic and it's far easier to use.
It also opens the door to making a proper DIY player - getting rid of the original cheap metal case completely and using wood or other materials.
Once I know it runs OK with all 6 transformers and the clock it's off to the timber yard.
I have a 3 layer thing in mind - all traffs on the bottom plank, green board, regulators and clock on the middle plank and the top will be smooth and polished with just the transport / optical unit protruding from the top.
Display front - centre somehow.
This way it's remote control only..
I'll stick with the top loading now it's reliable - less clanking plastic and it's far easier to use.
It also opens the door to making a proper DIY player - getting rid of the original cheap metal case completely and using wood or other materials.
Once I know it runs OK with all 6 transformers and the clock it's off to the timber yard.
I have a 3 layer thing in mind - all traffs on the bottom plank, green board, regulators and clock on the middle plank and the top will be smooth and polished with just the transport / optical unit protruding from the top.
Display front - centre somehow.
Attachments
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