DVD- Vs -CD player
 

"Keith G" wrote in message
...

"Trevor Wilson" wrote in message
...

"andy" wrote in message
oups.com...
As yet another owner of a Pioneer DV-575A I am curious about what the
above modifications will achieve and why?

**Output muting, via the use of BJTs has always been a sonic disaster,
IME. A relay contributes no distortion, whilst in the O/C mode. The
output IC used, whilst adequate, is hardly state of the art. Output ICs
in 1983 (ie: First generation) CD players were superior. In Philips
derived machines, that usually meant an NE5532/5534 chip. A fine chip,
back then and still a fine chip today. There are two, 220 Ohm resistors
in series with each O/P IC. These should be shorted (after replacing the
ICs with a more suitable device, of course). A 440 Ohm output impedance
is pitifully high. Additionally, it would be nice to organise a spilt
rail power supply, for the output IC. At present, it is powered by a
single rail supply, thus a large electrolytic coupling cap is required.

I suggest anyone who is interested, to compare the 575A to a decent,
contemporary CD (only) player, such as a Rotel RCD951 and report on any
differences.



All well and good Trevor, but like Andy says: 'why'...???

**Because Lord Pinkerton could do the job for almost no cost. The benefits
are tangible. For those not capable of doing the job, I feel it is probably
a toss-up as to if the value is there.


Don't see the point of buying a perfectly adequate budget player in the
first place and then spending *more* money on it.....???

**Me either. Still, I modded my own budget players. The cost was a little
time and some cheap chips and some relays I had lying around. The results
were worthwhile, in two out of the three instances. The bedroom system is
really too crappy to bother modding any player. The other rooms have quite
decent systems.


--
Trevor Wilson
www.rageaudio.com.au

DVD- Vs -CD player
 

On Fri, 01 Apr 2005 00:04:38 GMT, "Trevor Wilson"
wrote:


"Keith G" wrote in message
...

"Trevor Wilson" wrote in message
...

"andy" wrote in message
oups.com...
As yet another owner of a Pioneer DV-575A I am curious about what the
above modifications will achieve and why?

**Output muting, via the use of BJTs has always been a sonic disaster,
IME. A relay contributes no distortion, whilst in the O/C mode. The
output IC used, whilst adequate, is hardly state of the art. Output ICs
in 1983 (ie: First generation) CD players were superior. In Philips
derived machines, that usually meant an NE5532/5534 chip. A fine chip,
back then and still a fine chip today. There are two, 220 Ohm resistors
in series with each O/P IC. These should be shorted (after replacing the
ICs with a more suitable device, of course). A 440 Ohm output impedance
is pitifully high. Additionally, it would be nice to organise a spilt
rail power supply, for the output IC. At present, it is powered by a
single rail supply, thus a large electrolytic coupling cap is required.

I suggest anyone who is interested, to compare the 575A to a decent,
contemporary CD (only) player, such as a Rotel RCD951 and report on any
differences.

All well and good Trevor, but like Andy says: 'why'...???

**Because Lord Pinkerton could do the job for almost no cost. The benefits
are tangible. For those not capable of doing the job, I feel it is probably
a toss-up as to if the value is there.

You claim that the benefits are tangible, I suggest that they are
almost certainly only theoretical.

Don't see the point of buying a perfectly adequate budget player in the
first place and then spending *more* money on it.....???

**Me either. Still, I modded my own budget players. The cost was a little
time and some cheap chips and some relays I had lying around. The results
were worthwhile, in two out of the three instances. The bedroom system is
really too crappy to bother modding any player. The other rooms have quite
decent systems.

You did of course do this with two identical players, and compared
'before and after' sound quality?
--

Stewart Pinkerton | Music is Art - Audio is Engineering

DVD- Vs -CD player
 

On Fri, 01 Apr 2005 00:04:38 GMT, "Trevor Wilson"
wrote:


"Keith G" wrote in message
...

"Trevor Wilson" wrote in message
...

"andy" wrote in message
oups.com...
As yet another owner of a Pioneer DV-575A I am curious about what the
above modifications will achieve and why?

**Output muting, via the use of BJTs has always been a sonic disaster,
IME. A relay contributes no distortion, whilst in the O/C mode. The
output IC used, whilst adequate, is hardly state of the art. Output ICs
in 1983 (ie: First generation) CD players were superior. In Philips
derived machines, that usually meant an NE5532/5534 chip. A fine chip,
back then and still a fine chip today. There are two, 220 Ohm resistors
in series with each O/P IC. These should be shorted (after replacing the
ICs with a more suitable device, of course). A 440 Ohm output impedance
is pitifully high. Additionally, it would be nice to organise a spilt
rail power supply, for the output IC. At present, it is powered by a
single rail supply, thus a large electrolytic coupling cap is required.

I suggest anyone who is interested, to compare the 575A to a decent,
contemporary CD (only) player, such as a Rotel RCD951 and report on any
differences.

All well and good Trevor, but like Andy says: 'why'...???

**Because Lord Pinkerton could do the job for almost no cost. The benefits
are tangible. For those not capable of doing the job, I feel it is probably
a toss-up as to if the value is there.

You claim that the benefits are tangible, I suggest that they are
almost certainly only theoretical.

Don't see the point of buying a perfectly adequate budget player in the
first place and then spending *more* money on it.....???

**Me either. Still, I modded my own budget players. The cost was a little
time and some cheap chips and some relays I had lying around. The results
were worthwhile, in two out of the three instances. The bedroom system is
really too crappy to bother modding any player. The other rooms have quite
decent systems.

You did of course do this with two identical players, and compared
'before and after' sound quality?

My basic benchmark is that, since my 'off the shelf' Pioneer DV 575A
sounds identical to a 'high end' Meridian 588, it's vanishingly
unlikely that replacing a few parts inside the Pioneer willl make any
audible difference - except possibly for the worse!
--

Stewart Pinkerton | Music is Art - Audio is Engineering

DVD- Vs -CD player
 

Stewart Pinkerton wrote:

On Fri, 01 Apr 2005 00:04:38 GMT, "Trevor Wilson"
wrote:

**Me either. Still, I modded my own budget players. The cost was a little
time and some cheap chips and some relays I had lying around. The results
were worthwhile, in two out of the three instances. The bedroom system is
really too crappy to bother modding any player. The other rooms have quite
decent systems.


You did of course do this with two identical players, and compared
'before and after' sound quality?

It would be quite feasible to modify one channel and listen to
a mono recording, with some adjustment to the balance control.
If there is an improvement then the distortion should be heard
to one side. If there is no improvement then everything will be
exactly in the middle.

Or you could listen with the speaker between the +ve outputs
and just hear the difference between the channels. Adjust the
balance control for the lowest output. If, as Trevor says,
"The results were a very convincing 100%. Not subtle at all."
then that minimum would have to be pretty loud.

--
Eiron.

DVD- Vs -CD player
 

"Paul Dormer" wrote in message
...

Stewart is a technician (?) in a print room with a big gob.

Draw your own conclusions... ;-)


Bull's-eye!

I don't see Oinkie's posts any more, but I have no doubt that
he is the postal operative to whom you refer:-))

Iain

DVD- Vs -CD player
 

"Dave Plowman (News)" wrote in message
...

With CD under identical
circumstances few - very few, if any - will reliably tell which is which.

In my experience there is so much post production that goes on at
the mastering stage that often the master tape and the production
CD are wildly different. This may or may not be a good thing. But
it doesn't matter really, as the public have never heard the original
and so have no reference.


The whole objective of disc mastering, was to produce a lacquer
which sounded as close as possible to the original tape.
Any fool could make it sound different.

CD mastering is quite a simple process. Cutting a lacquer is
incredible difficult.

Iain

DVD- Vs -CD player
 

"Arny Krueger" wrote in message
...

Isn't 600 ohms the standard source impedance for audio production?

Yes, but you are conventiently missing out the rest of the
specification. 600 Ohms - balanced line on XLR.

Iain

DVD- Vs -CD player
 

"Eiron" wrote in message


If, as Trevor says,
"The results were a very convincing 100%. Not subtle at all."
then that minimum would have to be pretty loud.

You don't think that Trevor is capable of deceiving himself like the
rest of us ordinary mortals?

DVD- Vs -CD player
 

"Iain M Churches" wrote in message


"Arny Krueger" wrote in message
...

Isn't 600 ohms the standard source impedance for audio production?

Yes, but you are conventiently missing out the rest of the
specification. 600 Ohms - balanced line on XLR.

What's convenient about that?

DVD- Vs -CD player
 

"Arny Krueger" wrote in message
...
"Iain M Churches" wrote in message


"Arny Krueger" wrote in message
...

Isn't 600 ohms the standard source impedance for audio production?

Yes, but you are conventiently missing out the rest of the
specification. 600 Ohms - balanced line on XLR.

What's convenient about that?

Because Arny, my dear fellow, it doesn't mean a thing
if the OP is single ended. And if it is, the 400 Ohms is
pretty high (unless of course it's a cathode follower:-)))

Iain