"Jim Lesurf" wrote in message


Well, the measurements I made led to the spec that the
preamp using them had a SNR of 80dB for MM (RIAA) and
92dB ref to 150mV for line inputs. (And of course was OK
for signals up to 10Vrms, so gave a decent SNR for CD
Audio. Although that did arrive *after* the amp was
designed I did have it in mind.)

To put your SNR measurements into perspective, both input and output
voltages, and measurement bandwidth need to be known.

As previously explained this was going though three
12017s for RIAA and two for line inputs. The response was
flatter than 0.2dB over 20-20k simply as a result of the
capacitor values, etc, chosen.

Achieving flat response, or correct RIAA response is pretty much independent
of the op amp chosen, as long as there is ample GBW.

I have no quarrel with people using 5534's, etc, though.

5532/5534 are more optimal in low impedance situations.

Dave Plowman (News) wrote:
I need to knock up some stereo (domestic) line level amps with a gain
of 0-10dB.
Using a +/-15 volt supply. Anything better than the ol' NE 5543 for
this these days?

**The 5534/5532 were fabulous OP amps back in '82. MUCH better than the OP
that preceded them. It takes a seriously decent product to be any better
and, at that, there's only marginal audio differences in the newer ones.
Personally, I like the AD825. Technically, it is nicer than the 5532 and
slightly nicer sound-wise. The catch is that they are only available in SMD
variants and singles, at that. You need to source a carrier (Brown Dog) to
suit them.


--
Trevor Wilson
www.rageaudio.com.au

In article , Arny
Krueger
wrote:
"Jim Lesurf" wrote in message


Well, the measurements I made led to the spec that the preamp using
them had a SNR of 80dB for MM (RIAA) and 92dB ref to 150mV for line
inputs. (And of course was OK for signals up to 10Vrms, so gave a
decent SNR for CD Audio. Although that did arrive *after* the amp was
designed I did have it in mind.)

To put your SNR measurements into perspective, both input and output
voltages, and measurement bandwidth need to be known.

For the line inputs the ref level at the input was as I stated. 150mV rms.
Afraid I can't recall now if the bandwidth was 20-20k flat, or weighted.
Did the measurements nearly 30 years ago! :-)

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

In article ,
Trevor Wilson wrote:
Dave Plowman (News) wrote:
I need to knock up some stereo (domestic) line level amps with a gain
of 0-10dB.
Using a +/-15 volt supply. Anything better than the ol' NE 5543 for
this these days?

**The 5534/5532 were fabulous OP amps back in '82. MUCH better than the
OP that preceded them. It takes a seriously decent product to be any
better and, at that, there's only marginal audio differences in the
newer ones. Personally, I like the AD825. Technically, it is nicer than
the 5532 and slightly nicer sound-wise. The catch is that they are only
available in SMD variants and singles, at that. You need to source a
carrier (Brown Dog) to suit them.

Think I'll stick to the 5534. ;-)

--
*Reality is a crutch for people who can't handle drugs.

Dave Plowman London SW
To e-mail, change noise into sound.

"Trevor Wilson" wrote in message

Dave Plowman (News) wrote:
I need to knock up some stereo (domestic) line level
amps with a gain of 0-10dB.
Using a +/-15 volt supply. Anything better than the ol'
NE 5543 for this these days?

**The 5534/5532 were fabulous OP amps back in '82. MUCH
better than the OP that preceded them. It takes a
seriously decent product to be any better and, at that,
there's only marginal audio differences in the newer
ones. Personally, I like the AD825. Technically, it is
nicer than the 5532 and slightly nicer sound-wise.

Here we see Trevor perpetuating the myth that you can taste test the
"flavor" of different very good op amps in a general sort of way.

It turns out that in the application being discussed, namely a unity gain
buffer with output of 2 volts into a 10k load, even a 741 would probably
sound good.

There are some impressive new op amps that have recently come onto the
marketplace, but they are mostly a study in impressive numbers, and of use
for instrumentation.

In article ,
Arny Krueger wrote:
"Trevor Wilson" wrote in message

Dave Plowman (News) wrote:
I need to knock up some stereo (domestic) line level
amps with a gain of 0-10dB.
Using a +/-15 volt supply. Anything better than the ol'
NE 5543 for this these days?

**The 5534/5532 were fabulous OP amps back in '82. MUCH
better than the OP that preceded them. It takes a
seriously decent product to be any better and, at that,
there's only marginal audio differences in the newer
ones. Personally, I like the AD825. Technically, it is
nicer than the 5532 and slightly nicer sound-wise.

Here we see Trevor perpetuating the myth that you can taste test the
"flavor" of different very good op amps in a general sort of way.

It turns out that in the application being discussed, namely a unity
gain buffer with output of 2 volts into a 10k load, even a 741 would
probably sound good.

There are some impressive new op amps that have recently come onto the
marketplace, but they are mostly a study in impressive numbers, and of
use for instrumentation.


I actually want a variable gain of between 0 - 10 dB. So need an output of
rather more than 2 volts into 10k - plus headroom.
I know the 5534 will be fine for this - but given the age just wondered
if there was something better, as it were.

--
*Verbs HAS to agree with their subjects *

Dave Plowman London SW
To e-mail, change noise into sound.

In article , Arny
Krueger
wrote:


It turns out that in the application being discussed, namely a unity
gain buffer with output of 2 volts into a 10k load, even a 741 would
probably sound good.

FWIW More years ago that I care to remember a friend of mine bought his
first 'serious' hifi system. He had more money than I, so did this long
before I could afford anything comperable. He bought a QUAD system
33/303/ESLs. But wanted more control over the frequency response.

So I made him some simple 'bass shelf' tone controls ... using 741s.[1]
They actually worked quite decently well. He happily used the added
controls for many years. So yes, they actually sounded fine in the
circumstances, despite having zero 'street cred'. 8-]

That said, latterly I'd always automatically use better op amps since -
like using something like a Meridian DAC - they help give confidence that
you won't have any problems with the performance envelope. :-)

Slainte,

Jim

[1] IIRC The circuit was from a HFN of the era. Which I think also used
741s as this was in days before even TL071's, etc.

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

"Dave Plowman (News)" wrote in
message
In article
, Arny
Krueger wrote:
"Trevor Wilson" wrote in
message
Dave Plowman (News) wrote:
I need to knock up some stereo (domestic) line level
amps with a gain of 0-10dB.
Using a +/-15 volt supply. Anything better than the ol'
NE 5543 for this these days?

**The 5534/5532 were fabulous OP amps back in '82. MUCH
better than the OP that preceded them. It takes a
seriously decent product to be any better and, at that,
there's only marginal audio differences in the newer
ones. Personally, I like the AD825. Technically, it is
nicer than the 5532 and slightly nicer sound-wise.

Here we see Trevor perpetuating the myth that you can
taste test the "flavor" of different very good op amps
in a general sort of way.

It turns out that in the application being discussed,
namely a unity gain buffer with output of 2 volts into
a 10k load, even a 741 would probably sound good.

There are some impressive new op amps that have recently
come onto the marketplace, but they are mostly a study
in impressive numbers, and of use for instrumentation.


I actually want a variable gain of between 0 - 10 dB. So
need an output of rather more than 2 volts into 10k -
plus headroom.
I know the 5534 will be fine for this - but given the age
just wondered if there was something better, as it were.


Depends on how you define better. If by better you mean more GBW, lower
distoriton, noise and offset performance optimized for different working
impedance levels, lower power consumptiion, lower voltage power supply, high
voltage power supply and output, then there are other choices.

For general purpose applications and $0.50 or so, a 5534 or 5532 is pretty
hard to beat. Most of the audio projects I've built had 5534 or 5532 op amps
in them. In the past they were over $2.00.

The "hot" audio chips of the day a

LME49860 LME49710s, LME49720 LME49740 LM4562 LME49600

OPA 134, OPA 2134 OPA 4134 OPA365 OPA1161 OPA1162 OPA1612

On Sun, 28 Feb 2010 13:31:42 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Arny Krueger wrote:
"Trevor Wilson" wrote in message

Dave Plowman (News) wrote:
I need to knock up some stereo (domestic) line level
amps with a gain of 0-10dB.
Using a +/-15 volt supply. Anything better than the ol'
NE 5543 for this these days?

**The 5534/5532 were fabulous OP amps back in '82. MUCH
better than the OP that preceded them. It takes a
seriously decent product to be any better and, at that,
there's only marginal audio differences in the newer
ones. Personally, I like the AD825. Technically, it is
nicer than the 5532 and slightly nicer sound-wise.

Here we see Trevor perpetuating the myth that you can taste test the
"flavor" of different very good op amps in a general sort of way.

It turns out that in the application being discussed, namely a unity
gain buffer with output of 2 volts into a 10k load, even a 741 would
probably sound good.

There are some impressive new op amps that have recently come onto the
marketplace, but they are mostly a study in impressive numbers, and of
use for instrumentation.


I actually want a variable gain of between 0 - 10 dB. So need an output of
rather more than 2 volts into 10k - plus headroom.
I know the 5534 will be fine for this - but given the age just wondered
if there was something better, as it were.

Not entirely. You are OK with the 5532, but the 5534 is only stable
from a gain of 3 upwards. So if you go for the 5534, stick a couple of
resistors in front of it to drop the signal by say 12dB (to a quarter
of the original) and set the minimum gain to 4.

d

On Sun, 28 Feb 2010 17:59:55 GMT, (Don Pearce) wrote:

On Sun, 28 Feb 2010 13:31:42 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Arny Krueger wrote:
"Trevor Wilson" wrote in message

Dave Plowman (News) wrote:
I need to knock up some stereo (domestic) line level
amps with a gain of 0-10dB.
Using a +/-15 volt supply. Anything better than the ol'
NE 5543 for this these days?

**The 5534/5532 were fabulous OP amps back in '82. MUCH
better than the OP that preceded them. It takes a
seriously decent product to be any better and, at that,
there's only marginal audio differences in the newer
ones. Personally, I like the AD825. Technically, it is
nicer than the 5532 and slightly nicer sound-wise.

Here we see Trevor perpetuating the myth that you can taste test the
"flavor" of different very good op amps in a general sort of way.

It turns out that in the application being discussed, namely a unity
gain buffer with output of 2 volts into a 10k load, even a 741 would
probably sound good.

There are some impressive new op amps that have recently come onto the
marketplace, but they are mostly a study in impressive numbers, and of
use for instrumentation.


I actually want a variable gain of between 0 - 10 dB. So need an output of
rather more than 2 volts into 10k - plus headroom.
I know the 5534 will be fine for this - but given the age just wondered
if there was something better, as it were.

Not entirely. You are OK with the 5532, but the 5534 is only stable
from a gain of 3 upwards. So if you go for the 5534, stick a couple of
resistors in front of it to drop the signal by say 12dB (to a quarter
of the original) and set the minimum gain to 4.

d

Alternatively, of course, you can add an external compensation cap. I
think I'm right that 22pF is the value that guarantees unity gain
stability.

d