Tweaks to NAIm CDS -Part 2- valve output stage
- Thread starter audiojoy
- Start date
Oz that is really impressive I cannot make head or tail of it, but boy it looks so impressive. Spaghetti62 it certainly is. I wonder how it sounds over the original? I hope when i have finished mine we can meet up and compare them. I really would love to have details of the mods you have made and the stage by stage sound changes that occurred. How about a valve output buffer with an impedance matching transformer output???
Whereabouts are you?I am in Herts near Enfield London.
Luke
Whereabouts are you?I am in Herts near Enfield London.
Luke
Tonight i have had a friend round to evaluate the three stage transformations of the Naim CDS. Here is the results of our combined thoughts.
1) Original Naim CDS. Warm sounding, but constricted soundstage lacking air and detail good boogie factor but ultimately 'boring' to listen to. That last observation was not mine, i think my colleague means lacks top end extension and bottom end detail to give it dynamics and presence.
2) Modified CDS with its own Naim output filter/amp stage. Much more open and detailed. Great soundstaging air and detail. Much better dynamics, boogie factor about the same - not any better or worse than unmodded CDS.
3) Modified CDS with Valve output. All the changes identified in 2) but with a little more of everything, but more immediately obvious and suprising was that the 'Naim' Boogie factor was even BETTER than the other two. More coherent more drive and rhythm, more exciting to listen to.
The only slight lead to be had in the unmodded CDS was a somewhat more valve like tonal warmth and solidity to the imaging in the mid range and that was in the midrange only, the treble was muted and the bass was mono-tonal. Please note this does not mean the midrange was anywhere near as detailed or dynamic or articulate as the modded versions just that there was a slight warmth to the sound that gave a slightly more solid feel to the images; nonetheless a lot of the back ground images were still not helped by this attribute as they still didnot sound clear in the overall picture. But I believe when the sounstage almost doubles in size there is likely to be a little dilution in the power stakes. The valve unit and its supplies are of course not tweaked as yet and I haven't even started to roll the tubes which can have a dramatic effect on the tonality of the sound, especially if Mullards are used..
I was not going to add in the last comment because i thought it would give some of you Naim purists ammunition but in the context of the overall sound the unmodded CDS was lacking in every other area including timing rhythm and pace.
1) Original Naim CDS. Warm sounding, but constricted soundstage lacking air and detail good boogie factor but ultimately 'boring' to listen to. That last observation was not mine, i think my colleague means lacks top end extension and bottom end detail to give it dynamics and presence.
2) Modified CDS with its own Naim output filter/amp stage. Much more open and detailed. Great soundstaging air and detail. Much better dynamics, boogie factor about the same - not any better or worse than unmodded CDS.
3) Modified CDS with Valve output. All the changes identified in 2) but with a little more of everything, but more immediately obvious and suprising was that the 'Naim' Boogie factor was even BETTER than the other two. More coherent more drive and rhythm, more exciting to listen to.
The only slight lead to be had in the unmodded CDS was a somewhat more valve like tonal warmth and solidity to the imaging in the mid range and that was in the midrange only, the treble was muted and the bass was mono-tonal. Please note this does not mean the midrange was anywhere near as detailed or dynamic or articulate as the modded versions just that there was a slight warmth to the sound that gave a slightly more solid feel to the images; nonetheless a lot of the back ground images were still not helped by this attribute as they still didnot sound clear in the overall picture. But I believe when the sounstage almost doubles in size there is likely to be a little dilution in the power stakes. The valve unit and its supplies are of course not tweaked as yet and I haven't even started to roll the tubes which can have a dramatic effect on the tonality of the sound, especially if Mullards are used..
I was not going to add in the last comment because i thought it would give some of you Naim purists ammunition but in the context of the overall sound the unmodded CDS was lacking in every other area including timing rhythm and pace.
Luke, I am living in down cooling Finland, close to Helsinki...
Who ever could have imagined we will see a Naim based hybrid CDP here on PFM ?
And it happened this early, I mean in this particular century!
Wondering what Julian is doing right now..
A new animal this player - that's for sure.
We are speechless. As can be seen.
Oz
Who ever could have imagined we will see a Naim based hybrid CDP here on PFM ?
And it happened this early, I mean in this particular century!
Wondering what Julian is doing right now..
A new animal this player - that's for sure.
We are speechless. As can be seen.
Oz
Hi Cromodora, those small tube like silver units are in fact teflon caps replacing the already very good polystyrene caps in the filter section. The teflon is sandwiched between the outer and inner casing. The outer shiny metal is in fact live. The sound improvement over the polystyrenes is not dramatic but is well worthwhile. It simpler adds a little more of everything that the polystyrenes are already good at in partciular extra detail which helps give a more open and transparent feel.
Luke
Luke
FURTHER LISTENING TESTS
The story of the listening session continued well into the night, with more revelations.
You may have also read that i am a keen user of valve buffer stages after the Naim, which helps improve detail and dynamics slightly further and also enhances tonal colours as would be expected from a valve based buffer. However, the Valve buffer with those 'tiny' triodes is ESSENTIALLY NEUTRAL, I repeat ESSENTIALLY NEUTRAL SOUNDING. So don't you solid state guys go getting any ideas.
Well last night my mate brought along his own solid state buffer to replace my highly modified MF X10d. If I sounded astounded before then this was the BIGGEST improvement of all. ( But only possible because of the previous modifications.) It released a potential in the Naim i could never have imagined. The CDS therefore has unknown quantities of untapped potential only limited by the ancillary equipment. Even more so, the issue of impedance matching seems far more vital for the CDS than any other CD player I have ever used.
I think you must all be getting tired and sceptical of my constant remarks of how dramatic an improvement this mod and that mod makes. Never mind you guys,* I am getting tired of constantly repeating it. Again i will reiterate this cd player has shown ASTOUNDING (and I donot use this word lightly at all)potential for improvement with tweaking in a way i never could have imagined. This final upgrade using a finished off the shelf buffer unit was the definitive one. If i said that the dynamics and bass had improved dramatically then what was even more immediately noticeable was the sheer realism/presence of the musicians and the PRAT factor went up another whole level. Yes the 'boogie' factor, the 'naim' factor, the 'audionote' factor, the 'musicality' factor the 'emotional factor' the 'foot tapping' factor etc etc etc call it what you will.
Nuff said.
I am away this weekend so cant do anymore work. But NAim 62 is waiting at the post office and i will try some stuff not tried before by previous modders.
luke
The story of the listening session continued well into the night, with more revelations.
You may have also read that i am a keen user of valve buffer stages after the Naim, which helps improve detail and dynamics slightly further and also enhances tonal colours as would be expected from a valve based buffer. However, the Valve buffer with those 'tiny' triodes is ESSENTIALLY NEUTRAL, I repeat ESSENTIALLY NEUTRAL SOUNDING. So don't you solid state guys go getting any ideas.
Well last night my mate brought along his own solid state buffer to replace my highly modified MF X10d. If I sounded astounded before then this was the BIGGEST improvement of all. ( But only possible because of the previous modifications.) It released a potential in the Naim i could never have imagined. The CDS therefore has unknown quantities of untapped potential only limited by the ancillary equipment. Even more so, the issue of impedance matching seems far more vital for the CDS than any other CD player I have ever used.
I think you must all be getting tired and sceptical of my constant remarks of how dramatic an improvement this mod and that mod makes. Never mind you guys,* I am getting tired of constantly repeating it. Again i will reiterate this cd player has shown ASTOUNDING (and I donot use this word lightly at all)potential for improvement with tweaking in a way i never could have imagined. This final upgrade using a finished off the shelf buffer unit was the definitive one. If i said that the dynamics and bass had improved dramatically then what was even more immediately noticeable was the sheer realism/presence of the musicians and the PRAT factor went up another whole level. Yes the 'boogie' factor, the 'naim' factor, the 'audionote' factor, the 'musicality' factor the 'emotional factor' the 'foot tapping' factor etc etc etc call it what you will.
Nuff said.
I am away this weekend so cant do anymore work. But NAim 62 is waiting at the post office and i will try some stuff not tried before by previous modders.
luke
bottleneck
pfm Member
I'm grinning and laughing at this.It's like dropping your trousers to the queen!
PigletsDad
My intelligence test came back negative.
There are some technical reasons why valves have some merits as active devices in a CD output stage.
The device capacitances of semiconductors are intrinisically highly voltage dependent, while valves have capacitances that are almost perfectly independent of signal voltage.
The output stage of CDP has to deal with fast signal components from the DAC, square waves with energy up to a MHz or so. A semiconductor device will cross modulate this with the audio signal to a much greater extent than a valve will.
Good circuit design can minimise the semiconductor problems, but a valve is not a stupid choice - instead you get a bundle of other problems to control.
Valves are microphonic, more noisy than solid state, wear out and need funny power supplies - but they also have some intrinisic merits.
The device capacitances of semiconductors are intrinisically highly voltage dependent, while valves have capacitances that are almost perfectly independent of signal voltage.
The output stage of CDP has to deal with fast signal components from the DAC, square waves with energy up to a MHz or so. A semiconductor device will cross modulate this with the audio signal to a much greater extent than a valve will.
Good circuit design can minimise the semiconductor problems, but a valve is not a stupid choice - instead you get a bundle of other problems to control.
Valves are microphonic, more noisy than solid state, wear out and need funny power supplies - but they also have some intrinisic merits.