The mysterious NE5534 in the datasheet of PCM1792

[peranders]

WHY have Texas chosen NE5534 as an I/V converter followed by a LT1028

http://www-s.ti.com/sc/psheets/sles069/sles069.pdf

Please, explain for me the good reasons for this.

 

[jwb]

NE5534 is a good ol' low-noise op-amp. Quite popular in fact. Still, I'll be using a discreet I/V.

 

[mlloyd1]

Obviously, for voicing. The PCM1792 is clearly so clean and clinical that some grungy stuff must be added to make it "musical".

Why are you laughing? Oh, it's April 1st. Never mind ....


mlloyd1

WHY have Texas chosen NE5534 as an I/V converter followed by a LT1028 ...Please, explain for me the good reasons for this.

 

[peranders]

It's the same thing with AKM but they have ONLY NE5532/34. I'm really puzzled by why TI has chosen a LT1028 after a NE5534. Why put so much effort into one chip and then not recommend the best parts around the chip?

 

[fmak]

WHY have Texas chosen NE5534 as an I/V converter followed by a LT1028

http://www-s.ti.com/sc/psheets/sles069/sles069.pdf

Please, explain for me the good reasons for this.

------------------------------------------

These are design engineers, not audiophiles. The 5534 has lo noise, lo distortion but many stages inside. You can also alter compensation.

 

[carlosfm]

Bad beginning, happy end

Oh, I may know the answer.
Those engineers are hard-core tweakers.
They put the crap so that you can tweak it after it's done.
Do they talk about 8-pin sockets?

 

[leon]

NE5532/4 is one of the best
Maybe they should rename it and charge 10 times it's price
to keep some happy

 

[carlosfm]

NE5532/4

leon,
Do you know how old is it?
Do you know how these things have evoluted since then?
Oh, well...
Back to the TL072...

 

[fmak]

NE5532/4 is one of the best
Maybe they should rename it and charge 10 times it's price
to keep some happy

-----------------------------------

One of the best for measurement; one of the worst for sound. It defines the soincs of much pro equipment.

 

[leon]

Only electrons are older than it.
Still they haven't evoluted that much.
I have ears too.
I have used OPA627 and OPA2134.
No big differance.
Although OPA627 is better.
It's ok to say there are better ones but ist's not crap.

 

[carlosfm]

No big difference?

leon,
You'd better sell your Pioneer speakers and buy some decent ones.
Then you'll hear big differences between those op-amps.
No offense, huh?
Just joking.

 

[Bricolo]

we also want to use the PCM1792 instead of the PCM1704, because it's better, not because the PCM1704 is crap (and it's not!)

If you use a state of the art chip, why should you use cheap oarts around it?

 

[leon]

My speakers have scanspeak drivers they have no crossovers because I bi-amplify.
And finally I agree with you those enigneers know nothing about their job (designing those PCM's)

No offense, huh?
Just joking.

 

[carlosfm]

leon,
I hope you bi-amp with active crossovers before the power amps.
I like Scan-Speak speakers.
But i heard them playing badly due to bad design...
I'm not saying it's yor case.

 

[leon]

Hi carlosfm
Of course I use active crossover I would have no tweeter left by now if i didn't.
In this crossover I tried those op-amps I mentioned (and in the CD player).
Ok there's nothing more to argue about.
Case closed.

 

[BrianL]

So, what's the mystery about the NE5534 in a TI datasheet?
TI makes this part; I just looked up their datasheet on the TI web site

 

[capslock]

Yes, but they also make more expensive parts. For the PCM1730 and 1738 (both of which have the same or better THD+N as the 1792!), they recommended the OPA627 or 5534.

I have been listening to a 627 for years and years, it's in my preamp, but it is buffered with a class A four-transistor emitter follower. I am not sure it really likes to deliver 7 mA peak current.

Eric

 

[capslock]

And if they were concerned about noise, they should at least have used the 5534A.

 

[peranders]

So, what's the mystery about the NE5534 in a TI datasheet?
TI makes this part; I just looked up their datasheet on the TI web site

The mystery was that after a state of the art DAC connect an ancient opamp and THEN a low noise precision opamp! Can anyone tell me why?

 

[Terry Demol]

WHY have Texas chosen NE5534 as an I/V converter followed by a LT1028

http://www-s.ti.com/sc/psheets/sles069/sles069.pdf

Please, explain for me the good reasons for this.

I have spoken to people who have done extensive measurements on 5534 with AP. Apparently its main
sin is CM distortion and in inverting mode is one of
lowest distortion measuring OPA's.
It is interesting however, as BB always used to recommend
OPA627 for highest I-V performance.


Terry