The NE5534....misunderstood?

[millwood]

Originally posted by analog_sa
some very crappy wire

you need to be extra careful about those "crappy wires". a lot of them aren't "electron friendly" and force the electrons to jump up, down or spin in the wrong direction, adversely impacting the sound and creating way too much "jitters" from abrupt electron movements.

That is horrible for audio.

I wish someone can invent "electron carriers" that can smoothly transport electrons through those wires, much like a 1960s Buick Roadmaster crusing down I95. Then you will hear truly smooth music, not those crappy wires.

[jcarr]

>It is my recollection that the preferred 5534 was from Raytheon actually, and someone used to test them for distortion and rebrand them.<

I have also experienced that "drop-in replacement" designs may sound (and sometimes behave) differently, depending on who the manufacturer is. For example, the OP37 from PMI/AD has a different tonal balance (among other things) from the nominally compatible OPA37 by BB/TI. I suppose that the semiconductor processes are different, and possibly the internal schematics as well.

I don't mean to claim that either device sounds "better" than the other, but depending on which '37 you start with, the rest of the circuit may possibly benefit from being voiced using different componentry, and in some cases, different component values to get a similar-sounding final result.

It has also been my experience that the same device type from the same manufacturer may sound different, depending on the choice of package. A plastic package can sound different from a ceramic one. A metal can seemingly sounds different again, but it is not really possible to _properly_ compare a metal can against any sort of DIP8 package, due to the different shape and the resulting impact on the pcb layout.

All of the above is subjective, and will depend on the rest of the design, operating environment and individual listener. OTOH, I would imagine that the preference for a Raytheon 5534 started out as a subjective choice, too.

jonathan carr

[Thunau]

Originally posted by scott wurcer
The 5534 probably was first produced on 3" or even 2" wafers. The processes of these days are long gone and with good reason. I think every fab in the early 70's had someone nicknamed Larry, Moe, and Curly. Lots of knobs to tweak and plenty of 'secret sauce'.

The original planar process had no good PNP which had various workarounds. I would not be surprised if some of the ones today were just functional lookalikes in more modern processes (though probably not).

It is my recollection that the preferred 5534 was from Raytheon actually, and someone used to test them for distortion and rebrand them. I think MA332, but google shows only a few obscure references.

I have a tube of 50 Raytheon RC5532N that I picked up on eBay a couple of years ago. Their part number on the chip and the tube is RC306. The tube in addition has a DO44134-000 number on it. Assembled in Philippines. I don't have anything with socketed dual opamps to use as a comparison vehicle other than a Rolls unbalanced to balanced converter box. It has some BA4560's in it.

Originally posted by janneman


Yes, that hits a note. I spend a few months with Raytheon in Bedford, MA around 1980 on a NATO assignment, got a couple Raytheon '34-s from a friend, they were milspec, ceramic package, screened for very low noise, expensive as hell (if you had to pay for them..). Not sure if the number was MA334 or something else. I don't have those anymore, were used in a test instrument that I sold long time ago. Talking about wrong decisions, would probably be worth a fortune by now.

Jan Didden

How can you tell if the package is ceramic? the ones I have are black and have 532 3C1 stampped in white on the bottom.

[Bernhard]

Originally posted by Thunau
How can you tell if the package is ceramic?

Wow !

Imagine you have two tea cups, one is plastic and one is ceramic...

Can you tell ???

[Thunau]

Originally posted by Bernhard


Wow !

Imagine you have two tea cups, one is plastic and one is ceramic...

Can you tell ???

Thanks Smarty Pants,
Sometimes things are not as obvious.
Are you saying that the ceramic chips are red with "I love Buffalo" on them? That's what some ceramic tea cups I have look like.
But seriously, ceramics come in different colors. Black could be one of them. Plastics come in different densities too. Without going into scratch tests I wanted to know how to tell. I don't think it was that stupid of a question.

[Christer]

Maybe there are different types of ceramic packages, but all the
ones I have seen look quite different from the plastic ones.
They are built somewhat like a sandwich, consisting of two thin,
flat, rectangular pieces of ceramic with the chip in between
these and the pins also coming out between at the side. You
should clearly see that there is some kind of sealing compound
between the two pieces of ceramic. Further, I think all the ones
I have seen have been grey, rather than black like the plastic
packages.

[Bernhard]

Ceramic is usually brown as are most eproms.

Also the surface looks like ceramic, it is more heavy and feels colder if they are cold.

[Thunau]

Thanks, I ws hoping for that kind of answer.
I looked around and found a couple of images of cerdip


My Raytheons are not ceramic dip. Still, the difference in appearance is not that big.

[Christer]

Yes, that picture looks like what I tried to describe.

[Thunau]

I just took my Rolls Matchbox apart and compared 3 different op amps including the Raytheon RC5532N back to back. The other two were the stock Rohm BA4560 that came in the Rolls and a Burr Brown OPA2134. The application was balancing and driving a 20' line in to a JBL LSR25P nearfield studio monitor. The source- Toto IV SACD on a Philips SACD1000 player thorough a db preamp.
The stock opamp sounded a bit edgy and shallow. It made the SACD sound like a cheap CD player. The RC5532 sounded much more detailed and laid back in the midrange/treble (can't really compare the low end using a 5.25" woofer). The BB2134 had the same basic smooth and laid back character as the 5532 but with a touch more definition. The difference was not obvious as whe switching from the Rohm to 5532. I had to listen much more carefully and switch back and forth many times before grasping the differences. Both made the qualities of SACD come through.

In this particular setup the 5532 took the Matchbox 95% of the way to the performance of the 2134. I wonder why Rolls decided to save maybe $0.50 and went with the cheap opams. Maybe they preferred the more aggressive character of the cheap stuff. It does make the music cut through a background noise and exaggerates the midrange. I can see how it could be perceived as "good" in a project studio situation.

I have 47 of the RC5532 left and see no problems using them in some future projects. The money that otherwise would go toward $3.00 op amps can be spent upgrading caps and other parts.