Pete Cross wrote:
I didn't understand exactly what the 'speakers were. The earlier post
says ILP TL4, but I can't find any references for these. I know of ILP
as amplifier module manufacturers, but not for 'speakers. I also haven't
seen anything from Arnie casting doubt on the metal faculties of the
builder. Possibly my News server misses the odd post.

S.

My typo -------- the speakers are IPL Acoustics STL4's
Re Arny K, his suggestion that I'd screwed the design up and that National
had idiot proofed the new LM4562's gave me the impression he thought I was
the idiot, maybe I read too much into his comments. I still say though,
these sound much better than the 5532's.

Quote
" 2. a few yrs back I got samples from Analog Devices of a
low noise audio switch and a dc controlled vol chip (
0.002% thd ) I knocked them together with a couple of
5532's and have been enjoying them since ( from tv/dvd or
Technics CD into 4 x 75wrms mosfet amps and onto a pair
of ILP TL4's, ground/door and window shaking stuff and
very clear, or so I thought..... last week I got hold of
samples of National's LM4562 and replaced the 5532's, the
attack on drums is now much better and everything sounds
tighter.

Anybody who thinks that a LM4562 sounds better than a NE5532, both in
well-designed circuits, is suffering from specificaion-induced
constructor's ear. They are both free of audible distortion unless someone
screws up the design.


I've looked up the STL4s, I'm rather a fan of transmission line
'speakers. Generally, they need plenty of power, but I should think you
would have good reason to be happy with them.

As to the sound of different chips, I'm rather with Arnie on this one.
If the design is reasonably sound, and you get low distortion and noise,
then I don't think there would be any audible difference.

There are well accepted thresholds for the minimum noise, distortion and
frequency response variations which are audible. Once two amplifiers are
each below the threshold, whatever differences there are between them
will not be audible. For example, one amplifier having 0.05% distortion
and another having 0.01% won't sound any different, as it is generally
accepted that the threshold for distortion on programme material is at
least 0.1%. Analogue tape machines' output were rated as standard at the
3% THD level. Typical values were 1% at 0dB and 2-3% at 8dB above 0dB
which was considered peak level. At the time, few people complained that
the tape machine's distortion was ruining the music, and even today,
some artists like the analogue tape sound.

My two turntables both had 741s in the RIAA equaliser, which I replaced
with TL071s, only because I couldn't stand the idea of 741s. The TL071
is a direct plug-in replacement and the equalisers have their ICs on
sockets, so the replacement was easy. I didn't even have to solder
anything. I suppose the distortion of the TL071-equipped equaliser could
be lower than before (I didn't measure a before and after) but any
reduction would be swamped by the inherent distortion of vinyl and the
cartridge. I certainly haven't noticed any improvement, I just feel
better not having 741s in the signal path.

S.

As to the sound of different chips, I'm rather with Arnie on this one.
If the design is reasonably sound, and you get low distortion and noise,
then I don't think there would be any audible difference.

The LM4562's boast 20v/uS slew rate, the 5532's a measly 6v/uS ,
google for lm4652 and there are a few people saying same as me, there's more
detail and bass drums stand out amongst bass lines, I'm convinced they
didn't before, I guess I should put the 5532's back in but that's too much
messing and I have other fish to fry.........

I too would avoid 741's and LF351's too that seem to keep appearing...

Pete

Serge Auckland wrote:

My two turntables both had 741s in the RIAA equaliser, which I replaced
with TL071s, only because I couldn't stand the idea of 741s. The TL071
is a direct plug-in replacement and the equalisers have their ICs on
sockets, so the replacement was easy. I didn't even have to solder
anything. I suppose the distortion of the TL071-equipped equaliser could
be lower than before (I didn't measure a before and after) but any
reduction would be swamped by the inherent distortion of vinyl and the
cartridge. I certainly haven't noticed any improvement, I just feel
better not having 741s in the signal path.

Were the 741's used for high-level equalisation or as the input-devices?
My phono stage has an LM301, but only as a buffer after the long-tailed
pair and current mirror, and still sounds good. I don't see any reason
to replace it.

--
Eiron.

In article , Serge Auckland
wrote:


My two turntables both had 741s in the RIAA equaliser, which I replaced
with TL071s, only because I couldn't stand the idea of 741s. The TL071
is a direct plug-in replacement and the equalisers have their ICs on
sockets, so the replacement was easy. I didn't even have to solder
anything. I suppose the distortion of the TL071-equipped equaliser could
be lower than before (I didn't measure a before and after) but any
reduction would be swamped by the inherent distortion of vinyl and the
cartridge. I certainly haven't noticed any improvement, I just feel
better not having 741s in the signal path.

When I used to do such things I ended up designing a pre-amp using
HA12017's for all the gain stages. This despite the IC being intended by
Hitachi as an RIAA preamp for MM cartridge. I couldn't hear any real
differences between this and other ICs I tried - nor could anyone else I
tried the comparisons on at the time. However the HA12017 gave slightly
better results in terms of various specs, so coped with a wider range of
signals and output loads.

Took a little fiddling with the compensation to make it work, but turned
out OK. So far as I know, no-one else used the HA12017's like this, and I
guess they are long obsolete nowdays! :-)

FWIW When I tried using stabliser ICs like the 78/9XX familiy I also found
they tended to oscillate at a few MHz, so built PSU regulators with
discrete devices. So far as I recall, there were no audible effects I or
others noticed due to the oscillations. I had RF decoupled the power lines
on each individual IC, though. Just seemed a good idea to make a better
PSU.

Oh... and I don't really have a 'Desert Island Discs' list as I keep
changing my mind about what I am enjoying. Most recent has been the Rubbra
Symphonies (Hickock BBCNoW on Chandos) but before that it was a collection
of Benny Goodman Sextet on a Vocalion/Dutton CD. Before that I think it was
a recording of some Alain organ music from R3 performed by his sister in
1981 and 1986. Before that Pentangle... Special favourites from a while ago
include the Uchida sets of Schubert and Mozart sonatas, and some of the
re-issues of Duke Ellington with extra tracks.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

"Pete Cross" wrote in message


My typo -------- the speakers are IPL Acoustics STL4's
Re Arny K, his suggestion that I'd screwed the design up
and that National had idiot proofed the new LM4562's gave
me the impression he thought I was the idiot, maybe I
read too much into his comments.

You did read too much into my comments.

"idiot proofing" is one of those things that benefits all of us because we
all mistakes.

I still say though,
these sound much better than the 5532's.

If it gets you through the day...

Trust me, better ears than yours have done far more carefully controlled
listening tests, and come up empty.

Beware of constructor's ear.

ok, I'm biased.......
there must be something though.......
http://www.diyaudio.com/forums/showt...threadid=86276


or maybe my ears are shot as I spent 8yrs working under Hugh Banton ( VDGG )

Pete

"Serge Auckland" wrote in message
...
As things are quiet, I was musing on what my Desert Island Disks would be,
and also, what are my best recordings that I use for equipment evaluation.

For those not familiar with Desert Island Disks, this is a very
long-running series on BBC radio, which supposes you're shipwrecked on a
desert island with no hope of rescue, and you have to choose those 8
recordings (and only 8)to take with you.

Here are mine in no particular order, what are yours:-



I've had a think and conclude it is impossible to choose just 8 recordings
from my 'Top Ten' (which numbers probably over a hundred discs anyway) and
so would would grab a bunch of discs which I haven't played yet.

But......



6*. Vaughan Williams - The Lark Ascending. Musically I prefer the old
Boult/Bean recording, but it is hissy and has horrible modulation noise on
it. For a good modern version, the BBCSO Davis/Little recording is
excellent, and Tasmin Little does a pretty good job of the solo.



The Boult/Bean 'Larka' would be the disc I would take if I was allowed only
*one* - it's almost a daily (post prandial) ritual for me....!!

(As you know already! ;-)

"Keith G" wrote in message
...

"Serge Auckland" wrote in
message ...
As things are quiet, I was musing on what my Desert Island Disks would
be, and also, what are my best recordings that I use for equipment
evaluation.

For those not familiar with Desert Island Disks, this is a very
long-running series on BBC radio, which supposes you're shipwrecked on a
desert island with no hope of rescue, and you have to choose those 8
recordings (and only 8)to take with you.

Here are mine in no particular order, what are yours:-



I've had a think and conclude it is impossible to choose just 8 recordings
from my 'Top Ten' (which numbers probably over a hundred discs anyway) and
so would would grab a bunch of discs which I haven't played yet.



The second 'would' wants to be a 'probably'....

On 2007-02-24, Keith G wrote:

"Serge Auckland" wrote in message
...
As things are quiet, I was musing on what my Desert Island Disks would be,
and also, what are my best recordings that I use for equipment evaluation.
...

The Boult/Bean 'Larka' would be the disc I would take if I was allowed only
*one* - it's almost a daily (post prandial) ritual for me....!!

I am sure I have that in the LP archive which I am unable to play today.
I have distant memories of its quality. I must get a CD copy the next
time I raid Amazon.

(Actually I think I have now got copies of much of what I really liked
on LP in the late 1970s - probably a case of the first version you hear
defining the reference.)

--
John Phillips

"John Phillips" wrote in message
...
On 2007-02-24, Keith G wrote:

"Serge Auckland" wrote in
message
...
As things are quiet, I was musing on what my Desert Island Disks would
be,
and also, what are my best recordings that I use for equipment
evaluation.
...

The Boult/Bean 'Larka' would be the disc I would take if I was allowed
only
*one* - it's almost a daily (post prandial) ritual for me....!!

I am sure I have that in the LP archive which I am unable to play today.
I have distant memories of its quality. I must get a CD copy the next
time I raid Amazon.

(Actually I think I have now got copies of much of what I really liked
on LP in the late 1970s - probably a case of the first version you hear
defining the reference.)


Yes, I believe that entirely - not only music (discs &c.) but kit also,
speakers especially! I have had a number of emails (UK and US) from people
who are now trying to find the *same* kit they had a few decades ago!

(If your Larka LP is the EMI ASD 2329 and you really are not ever going to
play it, I would like to buy it off you - my copy has done many *hundreds*
of performances over the last few years and still sounds good, but it ain't
gonna last forever!! :-)