jccliu said:
This takes on an interesting twist. IIRC, Philips had their analog chips made by Signetics in Sunnyvale in the early 80's. The cooperation resulted in Philips taking over Signetics later on. They used the Signetics name for a few years after that. So, whatever those chips say, Philips, Signetics, it is very likely they come out of the same fab. But of course there still is the possibility that the shape of the logo on the plastic influences the sound. The fluent Signetics 'S' may make the reproduction more liquid than the squarish Philips logo.
Jan Didden
janneman said:
This takes on an interesting twist. IIRC, Philips had their analog chips made by Signetics in Sunnyvale in the early 80's. The cooperation resulted in Philips taking over Signetics later on. They used the Signetics name for a few years after that. So, whatever those chips say, Philips, Signetics, it is very likely they come out of the same fab. But of course there still is the possibility that the shape of the logo on the plastic influences the sound. The fluent Signetics 'S' may make the reproduction more liquid than the squarish Philips logo.
Jan Didden
Minor point, but Philips bought Signetics already in 1975, but the
Signetics name remaine for quite long as far as I can remember.
The new Signetics company was split off from Philips in 95, but
now recehcking the info I see that the claim to be in subcontracting,
so maybe they don't have any designs of their own??
http://www.signetics.com/about_1a.html
janneman said:
Maybe, on the other hand, my impression is that half of the
Koreans are called Kim, so maybe Lee is a very common
name too?
The interesting question is, does this new Signetics company
design and manufacture any own chips, or do they only do
subcontracting business? If the latter, then are there any
new chips sold as Signetics? I just checked some Signetics
5532 that I bought about a year ago, and they are marked
9236, that is, they were produced during the "Philips time"!!!
Maybe there is just a big stock of old chips lying around
somewhere??? Does anybody have Signetics chips made
later than 95?
Christer said:
Maybe, on the other hand, my impression is that half of the
Koreans are called Kim, so maybe Lee is a very common
name too?
The interesting question is, does this new Signetics company
design and manufacture any own chips, or do they only do
subcontracting business? If the latter, then are there any
new chips sold as Signetics? I just checked some Signetics
5532 that I bought about a year ago, and they are marked
9236, that is, they were produced during the "Philips time"!!!
Maybe there is just a big stock of old chips lying around
somewhere??? Does anybody have Signetics chips made
later than 95?
I'll check my stock. It does put a new twist on NOS, doesn't it.
Jan Didden
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.
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.
Hi guy´s,
What I remember it was A Philips desig from the first time and it was named TDA1034 before Philips let Signetics make it under NE5534
(I hit this thread late, so maybe some have talk about this before here in this post)
Ok, NE5534 are together with some other op-amps like AD797 and Jensen/Hardy 990 (for +/- 15 to 18 voltage supply) that have extremely low noise under 1 kohm Ri and it have also a good output end that can drive 600 ohm load with nearly full output swing in the audio band.
How it sounds,
ok, according my opinion the NE5534 in Philips, Signetics or Texas style don´t sounding good compare with in this day´s audio op-amps from Burr & Brown and Analoge Devices, but the NE5534 are very low cost and easy to get and often do a good work, but I will not say that it sounds pleasant.
(1969 I build my first op-amp based recording mixing console with Amelco 806 and Fairchild 741, this was not a hit, there we can talk about a hard sounding op-amp character)
Some body talk about 20 cascaded 741 op-amps, I think one it´s enough.
--Bo
What I remember it was A Philips desig from the first time and it was named TDA1034 before Philips let Signetics make it under NE5534
(I hit this thread late, so maybe some have talk about this before here in this post)
Ok, NE5534 are together with some other op-amps like AD797 and Jensen/Hardy 990 (for +/- 15 to 18 voltage supply) that have extremely low noise under 1 kohm Ri and it have also a good output end that can drive 600 ohm load with nearly full output swing in the audio band.
How it sounds,
ok, according my opinion the NE5534 in Philips, Signetics or Texas style don´t sounding good compare with in this day´s audio op-amps from Burr & Brown and Analoge Devices, but the NE5534 are very low cost and easy to get and often do a good work, but I will not say that it sounds pleasant.
(1969 I build my first op-amp based recording mixing console with Amelco 806 and Fairchild 741, this was not a hit, there we can talk about a hard sounding op-amp character)
Some body talk about 20 cascaded 741 op-amps, I think one it´s enough.
--Bo
scott wurcer said:
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
Straight Wire Test
Regarding KYW and his "straight wire test":
Why do most people seem to prefer an active preamp to a passive (even using the same volume control)?
This would appear to be a case where active devices (= signal manipulation, distortion etc) is preferable to straight wire.
Maybe I should try 20 X 741 is series??? Or maybe my wires are not straight enough? The electrons have a lot of corners to turn in op-amps, maybe vintage opamps with larger geometries do not have such tight corners?
BTW, I have not listened to NE553X for a while but I seem to recall it adds a fuzzy edge to the music and is a bit thin sounding compared to something like OPA627.
Regarding KYW and his "straight wire test":
Why do most people seem to prefer an active preamp to a passive (even using the same volume control)?
This would appear to be a case where active devices (= signal manipulation, distortion etc) is preferable to straight wire.
Maybe I should try 20 X 741 is series??? Or maybe my wires are not straight enough? The electrons have a lot of corners to turn in op-amps, maybe vintage opamps with larger geometries do not have such tight corners?
BTW, I have not listened to NE553X for a while but I seem to recall it adds a fuzzy edge to the music and is a bit thin sounding compared to something like OPA627.
Scott Wurcer
Ask Scott, he is or was a designer of Analog Opamps at Analog Devices. There are a number of problems with the 5534 just one of them as Scott pointed out was it was designed using all NPN parts, what a pain.
If I need a low noise bipolar input opamp the AD797 that Scott W. designed would be one of the first parts I'd consider.
Ask Scott, he is or was a designer of Analog Opamps at Analog Devices. There are a number of problems with the 5534 just one of them as Scott pointed out was it was designed using all NPN parts, what a pain.
If I need a low noise bipolar input opamp the AD797 that Scott W. designed would be one of the first parts I'd consider.
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