"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.


--
Trevor Wilson
www.rageaudio.com.au

"Stewart Pinkerton" wrote in message
...
On Wed, 30 Mar 2005 07:44:29 +1000, "Trevor Wilson"
wrote:


"Stewart Pinkerton" wrote in message
. ..
On Tue, 29 Mar 2005 18:33:40 +0100, "Keith G"
wrote:

"tox" wrote in message
...

Anyone else found DVD players as good or better than CD players for
playing
CD's?

Yep. Plenty of them, in particular the Pioneer DV-575a is very good and
will
play damn near *anything* and is only about a hundred spons.

(HFN doesn't seem to rate it much for CD though..... ;-)

HFN is sadly declined these days. I recently bought a 575A to replace
my trusty 515 for movies, and on CD it's sonically indistinguishable
from the Meridian 588. That's good enough for me..................

**The Meridian must be crap then. I suggest you perform several, simple
actions on your Pie-in-ear.

The Meridian is widely regarded as the state of the art in CD replay.

**That has been my experience.

Your pathetic namecalling is not evidence of a problem with the
Pioneer.

**Lighten up Lord Pinkerton. I'm just having fun with the name.


* Dump the muting transistors. Use nothing, or relays.
* Dump the output ICs and use something decent.
* Dump the series resistors after the output ICs.

Those actions will bring your Pie-in-ear up the level of a Rotel RCD951.

How about dumping your idiotic opinions? Indeed, how about actually
*listening*, instead of just banging on?

**No need. The output stage of the Pie-in-ear is the same as that used in a
thousand other cheap DVD players. They all benefit from rudimentary mods.

And, to answer your next question, I have done the obligatory blind tests.
The results were a very convincing 100%. Not subtle at all.


--
Trevor Wilson
www.rageaudio.com.au

"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'...???

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

"Keith G" wrote


Component Out - I'm not interested in multichannel sound)


Except cinema 'surround sound' of course....

Keith G wrote:
"Trevor Wilson" wrote in message
...

"andy" wrote in message
groups.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'...???

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


All looks quite bizarre to me ... but ... for anyone interested HFW (Jan
2005, pp.34-7) has some details: change output capacitors to Black Gate
- "really helped the Pioneer achieve its true potential"; overblown bass
"tamed"; high frequency "astounding"; "life-like ... sound blossomed"
etc. - you get the picture.
:-)
Rob

Thanks for the information.

I am unable to comment on a comparison between the Pioneer and a
current, more expensive CD player. However, I can confirm that the
result of a comparison between an old expensive CD player and the
Pioneer was that the same as the OPs and several of the other posters:
the modern consumer grade CD-DVD player was not inferior. Of course,
this does not mean it cannot be improved but I would suggest the
improvements are likely to be small.

Keith G wrote:


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

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


No, I just don't see the sense in that at all, if it makes it perform
better then why not spend more money on it?

I think even the most sceptical here would agree that cheap electrolytic
caps leave a lot to be desired, and replacing them in the output stage
with caps that have measurably better performance.

Using that logic Keith, do you want to swap the cerafine in your amp for
a standard RS cap? I will even offer you a tenner for your trouble
swaping it over.

I have heard a standard 575 and one with the sort of mods Trevor has
mentioned and I would suggest its £40 well spent.

--
Nick

"Trevor Wilson" wrote in message

"Stewart Pinkerton" wrote in message
...

HFN is sadly declined these days.

All those sighted listening evaluations have ruined their ears.

I recently bought a 575A to replace
my trusty 515 for movies, and on CD it's sonically
indistinguishable
from the Meridian 588. That's good enough for me.

I have the predecessor 563. As Keith says it will play darn near
anything in its native mode.

**The Meridian must be crap then. I suggest you perform several,
simple actions on your Pie-in-ear.

Here comes the knee-jerk tweako-freako violence with a soldering iron:

* Dump the muting transistors. Use nothing, or relays.

Why?

* Dump the output ICs and use something decent.

Why?

* Dump the series resistors after the output ICs.

Why?

Those actions will bring your Pie-in-ear up the level of a Rotel
RCD951.

Where's the reliable evidence that the Rotel sounds better or even any
different than a 563, 575 or whatever?

"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.

Musta never seen it done right.

A relay contributes no distortion,

As long as the contacts are good.

whilst in the O/C mode.

In which case there is no signal at all.

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.

Right, but just because it aint' a 5532 doesn't mean it sounds bad or
contributes any audible flaws at all.

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).

Why? Aren't building-out resistors good practice?

A 440 Ohm output impedance is pitifully high.

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

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.

What's wrong with a well-biased electrolytic?

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.

I suggest that Trevor quit pontificating and do some bias-controlled
listening tests of his own.

In article , Trevor Wilson
wrote:

"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.

FWIW The Quad 34 uses BJTs for output muting, but sounds fine to me.
Certainly doesn't sound like a 'disaster' to my ears. :-)


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).

Personally, I would always use series resistors at the output of a source
device or preamp. It allows you to define/limit the range of load
conditions the source output stage/IC will experience. Without this you may
produce problems in some cases.

A 440 Ohm output impedance is pitifully high.

Personally, for domestic sources I regard the order of 600 Ohms or less as
being fine unless there are special circumstances.

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.

Well I do use a Philips DVDR70 (DVD video recorder/player) as well as a
Meridian 200. However in both cases I send their digital output to a
Meridian 263 to obtain the sound. :-)

Slainte,

Jim

--
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