How many did you order? It's something i'd like to do. Any additional info would be much appreciated ;-)
I no longer have any boards for sale, but Ray has newly designed DOS boards for sale.
I've got three of Martin's LM317 regs driving the decoder chip now, adding to the four on the DAC. I cut trace by the decoder so I could add an extra capacitor for digital supply 1. All analogue supplies are decoupled by Black Gate FK and all digital by Black Gate NX.
This went very smoothly, except the disc keeps spinning slowly after the player has stopped now for some reason... I've invented perpetual motion! It's amazing what these players can do :-b
This went very smoothly, except the disc keeps spinning slowly after the player has stopped now for some reason... I've invented perpetual motion! It's amazing what these players can do :-b
Thanks! I got all my Black Gates from Michael Percy in the States, except the big FK smoothers in my amp which I got from a private Audiogon sale.
I've been interested in modding my hi-fi for years, initially after following Brent's PM66KI mods. It was the drying up of BG supply that spurred me into action, so I got all I needed just in time.
I've been interested in modding my hi-fi for years, initially after following Brent's PM66KI mods. It was the drying up of BG supply that spurred me into action, so I got all I needed just in time.
I've got three of Martin's LM317 regs driving the decoder chip now, adding to the four on the DAC. I cut trace by the decoder so I could add an extra capacitor for digital supply 1. All analogue supplies are decoupled by Black Gate FK and all digital by Black Gate NX.
This went very smoothly, except the disc keeps spinning slowly after the player has stopped now for some reason... I've invented perpetual motion! It's amazing what these players can do :-b
Ben, cool
Not a 63 but there's 8 317 jobbies in my old mule, oh and a flea.... and a few psu's.... and some blue tack.
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I agree with that lot. Heard the player before the new output, with CCS and then again after the CCS removal.
With CCS it was shrill and harsh seeming to falsely emphasise certain frequency bands and giving a false impression of better dynamics to leading edges of instruments. It simply didn't sound correct.
After the CCS removed it was back to its old self. Incredibly rich, neutral and correct.
Lee.
Hi Ricardo
I just placed the Welwyn RC55Y 0.1% metal film 1K8 from my older dos pcb.
I am fully happy with the sound now, I have her back and singing like she normally does. More dynamic, cleaner with greater detail in the bass and treble.
The CCS made the sound very narrow band for me with peaks at certain frequency points. CFP seems pretty much the same to be honest, maybe a slight improvement in mid band clarity + a small amount of dynamic gain.
Brent
I just placed the Welwyn RC55Y 0.1% metal film 1K8 from my older dos pcb.
I am fully happy with the sound now, I have her back and singing like she normally does. More dynamic, cleaner with greater detail in the bass and treble.
The CCS made the sound very narrow band for me with peaks at certain frequency points. CFP seems pretty much the same to be honest, maybe a slight improvement in mid band clarity + a small amount of dynamic gain.
Brent
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For me it is very slight, dynamics on well recorded music have improved and a slight mid band clarity lift. But any improvement is always welcomed.
The biggest thing for me is the fact I can fit the SPowers direct into the pcb now rather than tagging them on. The pcb is very well made and track layout is also better than the original pcbs.
I hope Ian tries the DOS with CCS and without to see what he finds
Brent
The biggest thing for me is the fact I can fit the SPowers direct into the pcb now rather than tagging them on. The pcb is very well made and track layout is also better than the original pcbs.
I hope Ian tries the DOS with CCS and without to see what he finds
Brent
Go to Texas Components - Precision Resistor & Microelectronics for all the information you like. You simply decide what you would like and then email and ask them how much it will be.
HI Brent,
I have found it interesting to read your comments regarding your new Dos, especially as they are a little bit at odds with my own experiences. The compound transistors as used in the design are a far superior circuit to the standard long tailed pair as the they stabilize the large voltage swings between +1.6v to -1.6v. How you hear the results of this is something else. And what I read in your notes is: the old sound is the long term reference to me and the new sound is different and I'm not sure I like it as much. But to make a true comparison one needs 2 players with Dos's, differing only in the addition of the compound pair. This may be hard to do, for obvious reasons. Even I, with several players and boards, did not do this. However, I did hear immediate improvement, in terms of musical clarity and definition, from the get go, and once I got the proper resistor between the pair I found a huge improvement in the bass, and there was nothing subtle about this last observation. And I admit to some surprise that you are not hearing the same. But then again, different player, different system, etc.
I have also used a compound pair to great success in the input stage of one of my preamps, going from a standard design ltp to a perfectly simulated cfp design, and again the difference was not subtle. In this application there really was not much voltage swing to stabilize, and my designer friend (not Ray btw) didn't think it would really do much. But upon hearing the results, agreed with me that it was a nice improvement.
Give your new DOS some time.
Steve
Hi Steve
I really don't know what to say other than what I have heard. 7 days of constant running in was enough for me and from my experience of upgrading etc I know it was simply not a matter of the new resistors etc running in. I tried a few fets and ran at different mA but never once had a linear sound. There were upper mid peaks and yes a tighter bass but on my player and revealing system it was false. My players does bass like pretty much no other, a dcs dac perhaps had similar results, deep and tight. Midrange and top end detail is sublime. The old dos let this all through.
Ricardo has too found a similar issue with CCS. Lee came over and heard it too and he is very familiar with my player and system.
Brent
I really don't know what to say other than what I have heard. 7 days of constant running in was enough for me and from my experience of upgrading etc I know it was simply not a matter of the new resistors etc running in. I tried a few fets and ran at different mA but never once had a linear sound. There were upper mid peaks and yes a tighter bass but on my player and revealing system it was false. My players does bass like pretty much no other, a dcs dac perhaps had similar results, deep and tight. Midrange and top end detail is sublime. The old dos let this all through.
Ricardo has too found a similar issue with CCS. Lee came over and heard it too and he is very familiar with my player and system.
Brent
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