Front end op amps for a Fender guitar amp, (Stage Lead circa 1982).

Which of these would be the proper replacement, looking for low noise, the
lead channel has very high gain.



Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

any help appreciated,

Vin Collins

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

Hi Tony,

Thanks, it wasn't clear on the Mouser site that it was packaging,
TI clarified it for me,,,thanks for the info,

Vin


"TonyP" wrote in message
...

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

Hi Tony,

Thanks, it wasn't clear on the Mouser site that it was packaging,
TI clarified it for me,,,thanks for the info,

Vin


"TonyP" wrote in message
...

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

Hi Tony,

Thanks, it wasn't clear on the Mouser site that it was packaging,
TI clarified it for me,,,thanks for the info,

Vin


"TonyP" wrote in message
...

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

Hi Tony,

Thanks, it wasn't clear on the Mouser site that it was packaging,
TI clarified it for me,,,thanks for the info,

Vin


"TonyP" wrote in message
...

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

thanks,

Vin


"François Yves Le Gal" wrote in message
...
On Tue, 11 May 2004 15:14:46 GMT, "JVC" wrote:

What would be the differences?

The op amp is exactly the same. The packaging differs: the P version comes
in PDIP, the D and DR in SOIC, the PS in SOP, the PW and PWR in TSSOP. If
your amp is from '82, we can presume the PDIP version has been used, but
you
should verify this.

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

thanks,

Vin


"François Yves Le Gal" wrote in message
...
On Tue, 11 May 2004 15:14:46 GMT, "JVC" wrote:

What would be the differences?

The op amp is exactly the same. The packaging differs: the P version comes
in PDIP, the D and DR in SOIC, the PS in SOP, the PW and PWR in TSSOP. If
your amp is from '82, we can presume the PDIP version has been used, but
you
should verify this.

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

thanks,

Vin


"François Yves Le Gal" wrote in message
...
On Tue, 11 May 2004 15:14:46 GMT, "JVC" wrote:

What would be the differences?

The op amp is exactly the same. The packaging differs: the P version comes
in PDIP, the D and DR in SOIC, the PS in SOP, the PW and PWR in TSSOP. If
your amp is from '82, we can presume the PDIP version has been used, but
you
should verify this.

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

thanks,

Vin


"François Yves Le Gal" wrote in message
...
On Tue, 11 May 2004 15:14:46 GMT, "JVC" wrote:

What would be the differences?

The op amp is exactly the same. The packaging differs: the P version comes
in PDIP, the D and DR in SOIC, the PS in SOP, the PW and PWR in TSSOP. If
your amp is from '82, we can presume the PDIP version has been used, but
you
should verify this.

If it is the "D" package, mouser has sockets, as well as radio shack.
Standard 8 pin socket. I use them when modding tube screamers.


On Tue, 11 May 2004 16:27:21 GMT, "JVC" wrote:

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

thanks,

Vin


"François Yves Le Gal" wrote in message
.. .
On Tue, 11 May 2004 15:14:46 GMT, "JVC" wrote:

What would be the differences?

The op amp is exactly the same. The packaging differs: the P version comes
in PDIP, the D and DR in SOIC, the PS in SOP, the PW and PWR in TSSOP. If
your amp is from '82, we can presume the PDIP version has been used, but
you
should verify this.

If it is the "D" package, mouser has sockets, as well as radio shack.
Standard 8 pin socket. I use them when modding tube screamers.


On Tue, 11 May 2004 16:27:21 GMT, "JVC" wrote:

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

thanks,

Vin


"François Yves Le Gal" wrote in message
.. .
On Tue, 11 May 2004 15:14:46 GMT, "JVC" wrote:

What would be the differences?

The op amp is exactly the same. The packaging differs: the P version comes
in PDIP, the D and DR in SOIC, the PS in SOP, the PW and PWR in TSSOP. If
your amp is from '82, we can presume the PDIP version has been used, but
you
should verify this.

If it is the "D" package, mouser has sockets, as well as radio shack.
Standard 8 pin socket. I use them when modding tube screamers.


On Tue, 11 May 2004 16:27:21 GMT, "JVC" wrote:

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

thanks,

Vin


"François Yves Le Gal" wrote in message
.. .
On Tue, 11 May 2004 15:14:46 GMT, "JVC" wrote:

What would be the differences?

The op amp is exactly the same. The packaging differs: the P version comes
in PDIP, the D and DR in SOIC, the PS in SOP, the PW and PWR in TSSOP. If
your amp is from '82, we can presume the PDIP version has been used, but
you
should verify this.

If it is the "D" package, mouser has sockets, as well as radio shack.
Standard 8 pin socket. I use them when modding tube screamers.


On Tue, 11 May 2004 16:27:21 GMT, "JVC" wrote:

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

thanks,

Vin


"François Yves Le Gal" wrote in message
.. .
On Tue, 11 May 2004 15:14:46 GMT, "JVC" wrote:

What would be the differences?

The op amp is exactly the same. The packaging differs: the P version comes
in PDIP, the D and DR in SOIC, the PS in SOP, the PW and PWR in TSSOP. If
your amp is from '82, we can presume the PDIP version has been used, but
you
should verify this.

"JVC" wrote:

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

It would be helpful for future work involving that part, but
not required.

http://www.mouser.com/catalog/618/828.pdf

Just get an 8 pin low profile DIP socket, any one will do OK.
I have a bunch of surplus AUGAT sockets that I use for things like
that, but generic sockets are fine.

"JVC" wrote:

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

It would be helpful for future work involving that part, but
not required.

http://www.mouser.com/catalog/618/828.pdf

Just get an 8 pin low profile DIP socket, any one will do OK.
I have a bunch of surplus AUGAT sockets that I use for things like
that, but generic sockets are fine.

"JVC" wrote:

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

It would be helpful for future work involving that part, but
not required.

http://www.mouser.com/catalog/618/828.pdf

Just get an 8 pin low profile DIP socket, any one will do OK.
I have a bunch of surplus AUGAT sockets that I use for things like
that, but generic sockets are fine.

"JVC" wrote:

Would it be wise convert to socket, if so any part #'s (mouser) recommended.

It would be helpful for future work involving that part, but
not required.

http://www.mouser.com/catalog/618/828.pdf

Just get an 8 pin low profile DIP socket, any one will do OK.
I have a bunch of surplus AUGAT sockets that I use for things like
that, but generic sockets are fine.

"JVC" wrote in message ...
Hi Tony,

Thanks, it wasn't clear on the Mouser site that it was packaging,
TI clarified it for me,,,thanks for the info,

There's a "description" column on the Mouser page that gives the package type for each item, as well as a link to the
pdf data sheet(s) which have the packaging info.

http://www.mouser.com/index.cfm?&han...*&N=0&crc=true

IC sockets are a Very Bad Idea for guitar amps and other equipment that gets moved a lot. Between the vibration caused
by playing through the amp and the beating the amp takes being moved from one gig to another, the socket to IC interface
will sooner or later become intermittant.

Fred


Vin


"TonyP" wrote in message
...

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

"JVC" wrote in message ...
Hi Tony,

Thanks, it wasn't clear on the Mouser site that it was packaging,
TI clarified it for me,,,thanks for the info,

There's a "description" column on the Mouser page that gives the package type for each item, as well as a link to the
pdf data sheet(s) which have the packaging info.

http://www.mouser.com/index.cfm?&han...*&N=0&crc=true

IC sockets are a Very Bad Idea for guitar amps and other equipment that gets moved a lot. Between the vibration caused
by playing through the amp and the beating the amp takes being moved from one gig to another, the socket to IC interface
will sooner or later become intermittant.

Fred


Vin


"TonyP" wrote in message
...

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

"JVC" wrote in message ...
Hi Tony,

Thanks, it wasn't clear on the Mouser site that it was packaging,
TI clarified it for me,,,thanks for the info,

There's a "description" column on the Mouser page that gives the package type for each item, as well as a link to the
pdf data sheet(s) which have the packaging info.

http://www.mouser.com/index.cfm?&han...*&N=0&crc=true

IC sockets are a Very Bad Idea for guitar amps and other equipment that gets moved a lot. Between the vibration caused
by playing through the amp and the beating the amp takes being moved from one gig to another, the socket to IC interface
will sooner or later become intermittant.

Fred


Vin


"TonyP" wrote in message
...

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

"JVC" wrote in message ...
Hi Tony,

Thanks, it wasn't clear on the Mouser site that it was packaging,
TI clarified it for me,,,thanks for the info,

There's a "description" column on the Mouser page that gives the package type for each item, as well as a link to the
pdf data sheet(s) which have the packaging info.

http://www.mouser.com/index.cfm?&han...*&N=0&crc=true

IC sockets are a Very Bad Idea for guitar amps and other equipment that gets moved a lot. Between the vibration caused
by playing through the amp and the beating the amp takes being moved from one gig to another, the socket to IC interface
will sooner or later become intermittant.

Fred


Vin


"TonyP" wrote in message
...

"JVC" wrote in message
...
Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

Probably the package type.
Have you checked the TI web site?
http://focus.ti.com/

TonyP.

"JVC" wrote in message .. .
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982).

Which of these would be the proper replacement, looking for low noise, the
lead channel has very high gain.



Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

any help appreciated,

Vin Collins


The 4558 wasn't exactly a brand new design even back then. Maybe
somebody here can recommend something newer with the same pin-out
that'll work in its place. Like the other poster said, don't use a
socket on a piece of gear that's going to get tossed into the back of
the truck at the end of the night when everybody wants to load up fast
and get gone.

"JVC" wrote in message .. .
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982).

Which of these would be the proper replacement, looking for low noise, the
lead channel has very high gain.



Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

any help appreciated,

Vin Collins


The 4558 wasn't exactly a brand new design even back then. Maybe
somebody here can recommend something newer with the same pin-out
that'll work in its place. Like the other poster said, don't use a
socket on a piece of gear that's going to get tossed into the back of
the truck at the end of the night when everybody wants to load up fast
and get gone.

"JVC" wrote in message .. .
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982).

Which of these would be the proper replacement, looking for low noise, the
lead channel has very high gain.



Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

any help appreciated,

Vin Collins


The 4558 wasn't exactly a brand new design even back then. Maybe
somebody here can recommend something newer with the same pin-out
that'll work in its place. Like the other poster said, don't use a
socket on a piece of gear that's going to get tossed into the back of
the truck at the end of the night when everybody wants to load up fast
and get gone.

"JVC" wrote in message .. .
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982).

Which of these would be the proper replacement, looking for low noise, the
lead channel has very high gain.



Texas Instruments has the following part numbers.

RC4558D
RC4558DR
RC4558P
RC4558PSR
RC4558PWR

What would be the differences?

any help appreciated,

Vin Collins


The 4558 wasn't exactly a brand new design even back then. Maybe
somebody here can recommend something newer with the same pin-out
that'll work in its place. Like the other poster said, don't use a
socket on a piece of gear that's going to get tossed into the back of
the truck at the end of the night when everybody wants to load up fast
and get gone.

"unitron" in message m...
The 4558 wasn't exactly a brand new design even back then. Maybe
somebody here can recommend something newer with the same pin-out
that'll work in its place.

Wow, same op amp came up in more detail a month or two ago on
sci.electronics.design.

To give you what background I can offhand, this product (originally either
Motorola MC1558/MC1458 or Signetics SE/NE5558, I don't recall exactly, circa
1969, later second-sourced by the entire semiconductor industry) is a
classic dual version of the uA741 class of op amp. (I first mentioned a
1558 in print in _Popular Electronics_ in 1973 and received various
questions on where to find it.) The basic amplifier design is widely
considered easy to use by equipment designers, but key electrical specs for
audio are weak enough (especially, 1-2MHz gain-bandwidth product and 1-2
V/usec slew rate) to be either obviously or subtly audible in audio
applications -- unless it is out of the audio path (in a control function or
power-supply or something). As a concrete example for any product designers
reading this, at 20kHz this amplifier has an open-loop gain of 50-100 V/V,
so a 1 Vrms sinusoid output (2.8 V Peak-to-Peak) means at least 28 mV P-P
across the amplifier's + - input pins -- which go into a stacked bipolar
emitter-coupled pair stage linear only for differences much below 26 mV at
typical temperatures and hard-limiting at something like 52mV
differential -- leading to important distortion levels at audio, except for
"small-signal" output conditions.

That's just the bad news. The good news is that maybe that particular audio
product sounded the way it did because of this op amp. And that this
particular pin-out is very common on 8-pin dual operational amplifiers
(compare pin-outs first, if considering alternatives) so that many others
could be substituted, and some of them are especially good for audio, unlike
the 1558 (and 741). Sorry I don't have the latest at hand, but I did post
general op-amp tutorial info related to audio in the past articles below and
in others too, available (like many useful past postings) by searching an
online Usenet archive (such as, currently, groups.google.com):

Subject: About op amps for audio applications (long)
Newsgroups: sci.electronics,rec.audio
Message-ID:
Date: 23 May 88 14:43:23 GMT

Subject: The maligned 5534 op amp (Was: Chesky's 128x oversamp)
Newsgroups: rec.audio.high-end
Message-ID:
Date: 8 Jul 91 13:19:07 GMT


Hope this is helpful. -- Max Hauser

"unitron" in message m...
The 4558 wasn't exactly a brand new design even back then. Maybe
somebody here can recommend something newer with the same pin-out
that'll work in its place.

Wow, same op amp came up in more detail a month or two ago on
sci.electronics.design.

To give you what background I can offhand, this product (originally either
Motorola MC1558/MC1458 or Signetics SE/NE5558, I don't recall exactly, circa
1969, later second-sourced by the entire semiconductor industry) is a
classic dual version of the uA741 class of op amp. (I first mentioned a
1558 in print in _Popular Electronics_ in 1973 and received various
questions on where to find it.) The basic amplifier design is widely
considered easy to use by equipment designers, but key electrical specs for
audio are weak enough (especially, 1-2MHz gain-bandwidth product and 1-2
V/usec slew rate) to be either obviously or subtly audible in audio
applications -- unless it is out of the audio path (in a control function or
power-supply or something). As a concrete example for any product designers
reading this, at 20kHz this amplifier has an open-loop gain of 50-100 V/V,
so a 1 Vrms sinusoid output (2.8 V Peak-to-Peak) means at least 28 mV P-P
across the amplifier's + - input pins -- which go into a stacked bipolar
emitter-coupled pair stage linear only for differences much below 26 mV at
typical temperatures and hard-limiting at something like 52mV
differential -- leading to important distortion levels at audio, except for
"small-signal" output conditions.

That's just the bad news. The good news is that maybe that particular audio
product sounded the way it did because of this op amp. And that this
particular pin-out is very common on 8-pin dual operational amplifiers
(compare pin-outs first, if considering alternatives) so that many others
could be substituted, and some of them are especially good for audio, unlike
the 1558 (and 741). Sorry I don't have the latest at hand, but I did post
general op-amp tutorial info related to audio in the past articles below and
in others too, available (like many useful past postings) by searching an
online Usenet archive (such as, currently, groups.google.com):

Subject: About op amps for audio applications (long)
Newsgroups: sci.electronics,rec.audio
Message-ID:
Date: 23 May 88 14:43:23 GMT

Subject: The maligned 5534 op amp (Was: Chesky's 128x oversamp)
Newsgroups: rec.audio.high-end
Message-ID:
Date: 8 Jul 91 13:19:07 GMT


Hope this is helpful. -- Max Hauser

"unitron" in message m...
The 4558 wasn't exactly a brand new design even back then. Maybe
somebody here can recommend something newer with the same pin-out
that'll work in its place.

Wow, same op amp came up in more detail a month or two ago on
sci.electronics.design.

To give you what background I can offhand, this product (originally either
Motorola MC1558/MC1458 or Signetics SE/NE5558, I don't recall exactly, circa
1969, later second-sourced by the entire semiconductor industry) is a
classic dual version of the uA741 class of op amp. (I first mentioned a
1558 in print in _Popular Electronics_ in 1973 and received various
questions on where to find it.) The basic amplifier design is widely
considered easy to use by equipment designers, but key electrical specs for
audio are weak enough (especially, 1-2MHz gain-bandwidth product and 1-2
V/usec slew rate) to be either obviously or subtly audible in audio
applications -- unless it is out of the audio path (in a control function or
power-supply or something). As a concrete example for any product designers
reading this, at 20kHz this amplifier has an open-loop gain of 50-100 V/V,
so a 1 Vrms sinusoid output (2.8 V Peak-to-Peak) means at least 28 mV P-P
across the amplifier's + - input pins -- which go into a stacked bipolar
emitter-coupled pair stage linear only for differences much below 26 mV at
typical temperatures and hard-limiting at something like 52mV
differential -- leading to important distortion levels at audio, except for
"small-signal" output conditions.

That's just the bad news. The good news is that maybe that particular audio
product sounded the way it did because of this op amp. And that this
particular pin-out is very common on 8-pin dual operational amplifiers
(compare pin-outs first, if considering alternatives) so that many others
could be substituted, and some of them are especially good for audio, unlike
the 1558 (and 741). Sorry I don't have the latest at hand, but I did post
general op-amp tutorial info related to audio in the past articles below and
in others too, available (like many useful past postings) by searching an
online Usenet archive (such as, currently, groups.google.com):

Subject: About op amps for audio applications (long)
Newsgroups: sci.electronics,rec.audio
Message-ID:
Date: 23 May 88 14:43:23 GMT

Subject: The maligned 5534 op amp (Was: Chesky's 128x oversamp)
Newsgroups: rec.audio.high-end
Message-ID:
Date: 8 Jul 91 13:19:07 GMT


Hope this is helpful. -- Max Hauser

"unitron" in message m...
The 4558 wasn't exactly a brand new design even back then. Maybe
somebody here can recommend something newer with the same pin-out
that'll work in its place.

Wow, same op amp came up in more detail a month or two ago on
sci.electronics.design.

To give you what background I can offhand, this product (originally either
Motorola MC1558/MC1458 or Signetics SE/NE5558, I don't recall exactly, circa
1969, later second-sourced by the entire semiconductor industry) is a
classic dual version of the uA741 class of op amp. (I first mentioned a
1558 in print in _Popular Electronics_ in 1973 and received various
questions on where to find it.) The basic amplifier design is widely
considered easy to use by equipment designers, but key electrical specs for
audio are weak enough (especially, 1-2MHz gain-bandwidth product and 1-2
V/usec slew rate) to be either obviously or subtly audible in audio
applications -- unless it is out of the audio path (in a control function or
power-supply or something). As a concrete example for any product designers
reading this, at 20kHz this amplifier has an open-loop gain of 50-100 V/V,
so a 1 Vrms sinusoid output (2.8 V Peak-to-Peak) means at least 28 mV P-P
across the amplifier's + - input pins -- which go into a stacked bipolar
emitter-coupled pair stage linear only for differences much below 26 mV at
typical temperatures and hard-limiting at something like 52mV
differential -- leading to important distortion levels at audio, except for
"small-signal" output conditions.

That's just the bad news. The good news is that maybe that particular audio
product sounded the way it did because of this op amp. And that this
particular pin-out is very common on 8-pin dual operational amplifiers
(compare pin-outs first, if considering alternatives) so that many others
could be substituted, and some of them are especially good for audio, unlike
the 1558 (and 741). Sorry I don't have the latest at hand, but I did post
general op-amp tutorial info related to audio in the past articles below and
in others too, available (like many useful past postings) by searching an
online Usenet archive (such as, currently, groups.google.com):

Subject: About op amps for audio applications (long)
Newsgroups: sci.electronics,rec.audio
Message-ID:
Date: 23 May 88 14:43:23 GMT

Subject: The maligned 5534 op amp (Was: Chesky's 128x oversamp)
Newsgroups: rec.audio.high-end
Message-ID:
Date: 8 Jul 91 13:19:07 GMT


Hope this is helpful. -- Max Hauser

"Max Hauser" wrote in message

To give you what background I can offhand, this product (originally either
Motorola MC1558/MC1458 or Signetics SE/NE5558, I don't recall exactly,
circa
1969, later second-sourced by the entire semiconductor industry) is a
classic dual version of the uA741 class of op amp.



** The RC4558 was *introduced * in 1974 by Raytheon - it is of quite
*different* design to the uA741 (released in 1968) or MC1458 (a dual 741).

For a start the two input transistors in a 4558 are PNP and not NPN as in
a 741, the gain bandwidth product and slew rates are 2 to 3 times greater
and the self noise level is about 6 to 8 dB less.

More recently the 4559 and 4560 have been produced with further
improvements in the above characteristics - they are widely available from
several makers.




............. Phil

"Max Hauser" wrote in message

To give you what background I can offhand, this product (originally either
Motorola MC1558/MC1458 or Signetics SE/NE5558, I don't recall exactly,
circa
1969, later second-sourced by the entire semiconductor industry) is a
classic dual version of the uA741 class of op amp.



** The RC4558 was *introduced * in 1974 by Raytheon - it is of quite
*different* design to the uA741 (released in 1968) or MC1458 (a dual 741).

For a start the two input transistors in a 4558 are PNP and not NPN as in
a 741, the gain bandwidth product and slew rates are 2 to 3 times greater
and the self noise level is about 6 to 8 dB less.

More recently the 4559 and 4560 have been produced with further
improvements in the above characteristics - they are widely available from
several makers.




............. Phil

"Max Hauser" wrote in message

To give you what background I can offhand, this product (originally either
Motorola MC1558/MC1458 or Signetics SE/NE5558, I don't recall exactly,
circa
1969, later second-sourced by the entire semiconductor industry) is a
classic dual version of the uA741 class of op amp.



** The RC4558 was *introduced * in 1974 by Raytheon - it is of quite
*different* design to the uA741 (released in 1968) or MC1458 (a dual 741).

For a start the two input transistors in a 4558 are PNP and not NPN as in
a 741, the gain bandwidth product and slew rates are 2 to 3 times greater
and the self noise level is about 6 to 8 dB less.

More recently the 4559 and 4560 have been produced with further
improvements in the above characteristics - they are widely available from
several makers.




............. Phil

"Max Hauser" wrote in message

To give you what background I can offhand, this product (originally either
Motorola MC1558/MC1458 or Signetics SE/NE5558, I don't recall exactly,
circa
1969, later second-sourced by the entire semiconductor industry) is a
classic dual version of the uA741 class of op amp.



** The RC4558 was *introduced * in 1974 by Raytheon - it is of quite
*different* design to the uA741 (released in 1968) or MC1458 (a dual 741).

For a start the two input transistors in a 4558 are PNP and not NPN as in
a 741, the gain bandwidth product and slew rates are 2 to 3 times greater
and the self noise level is about 6 to 8 dB less.

More recently the 4559 and 4560 have been produced with further
improvements in the above characteristics - they are widely available from
several makers.




............. Phil

"Phil Allison" in ...

"Max Hauser" wrote:

** The RC4558 was *introduced * in 1974 by Raytheon

Sorry! I screwed up there, forgetting the actual RC4558 (and the focus of
this thread) in the haunting maze of other and more common dual op amps of
at least three distinct designs all called some kind of -558, as follows (if
you're interested). It was not the RC4558 I referred to in the previous
posting. More on op amps in general at the end, and a glorious historical
link.

Some history. The original, Motorola MC1558, was explicitly a dual 741.
Its significance was partly 8-pin package, unlike earlier Fairchild and
National 14-pin dual-741 types. (I also remember an early dual 741 from
Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s
so don't hold me to precision there.) The MC1558 was supplemented by
Motorola's high-speed version (MC1558S) as Jim Thompson, working there at
the time, recalled recently, 22-Feb-04 in sci.electronics.design -- the
second distinct circuit. These early "558" op amps were popular and became
second-sourced soon by other vendors one of which, as I recall, called
theirs "5558" to conform to the firm's product numbering. None of these
products was the RC4558, a later design with PNP input stage. (Motorola
itself then proceeded itself to second-source the RC4558 too.) In 1974 (not
1973) I put a circuit in _Popular Electronics_ calling for a "558-type" dual
op amp, intending a 1558 or one of its second-sourced, slightly
different-numbered versions. This yielded a file of correspondence to me in
California from hobbyists as distant as Selangor, Malaysia (I just checked
the file) full of requests for clarification on the "558" part number, an
issue haunting me still, as you see. :-(

- it is of quite *different* design to the uA741 (released
in 1968) or MC1458 (a dual 741).

Regarding comparisons to 741, Mr Allison employs a close-up lens, mine is a
zoom. In the context of the popular Philbrick K2-W and K2-XA vacuum-tube
DC-coupled op amps (still in use! _mirabile dictu_), the many successful
solid-state pre-monolithic op amps including the breakthrough Philbrick P2
and P65, low-cost Nexus SQ10A, several from NV Philips; early monolithic
generations of low-voltage three-stage, then high-voltage three-stage, then
high-voltage two-stage designs (Fullagar's 741, Widlar's LM101), the duals
we are discussing, the low-cost National "quad 741" (Fredrickson's LM324),
Lovelace's NE5532, Huijsing ("Professor Op Amp")'s NE5534, the mixed-process
op amps of the middle 1970s, and many others, it's possible to observe in
the RC4558a bipolar design with mirror-loaded input stage, NPN Darlington
second gain stage, complementary emitter-follower output stage, and internal
single-pole minor-loop frequency compensation (popularized by the Philbrick
K2 family, not the much later 741 as the young engineers suppose). It is
possible to find designs that are indeed nearer to the original 741, but not
many -- which is why some people would call it a 741-class design. (It also
has the internal fixed unity-gain freq compensation decried as a limitation
in Jim Roberge's classic op-amp design text -- I cited the result, a
performance limitation apt to yield audible distortion.) I have some
experience designing monolithic op amps (one-, two-, and three-gain-stage
types, bipolar and MOS, some fast, some low-noise, some just weird) so maybe
I lump more designs into the "741 class" than the next person might choose
to do.

If anyone would like to really learn about op amps and their ways, from a
long focus, one of the Primary Sources that taught the world about op amps,
the 1965 Philbrick Applications Manual, is now online, thanks in part I
believe to one of its authors (Dan Sheingold). The current link is

http://www.analog.com/library/analog...mplifiers.html

-- be sure to re-assemble and paste into your browser, if the line gets
wrapped to more than one.

Again I hope this will find some use to someone, and apologize for still
mixing "558" part numbers after thirty years. -- Max Hauser

"Phil Allison" in ...

"Max Hauser" wrote:

** The RC4558 was *introduced * in 1974 by Raytheon

Sorry! I screwed up there, forgetting the actual RC4558 (and the focus of
this thread) in the haunting maze of other and more common dual op amps of
at least three distinct designs all called some kind of -558, as follows (if
you're interested). It was not the RC4558 I referred to in the previous
posting. More on op amps in general at the end, and a glorious historical
link.

Some history. The original, Motorola MC1558, was explicitly a dual 741.
Its significance was partly 8-pin package, unlike earlier Fairchild and
National 14-pin dual-741 types. (I also remember an early dual 741 from
Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s
so don't hold me to precision there.) The MC1558 was supplemented by
Motorola's high-speed version (MC1558S) as Jim Thompson, working there at
the time, recalled recently, 22-Feb-04 in sci.electronics.design -- the
second distinct circuit. These early "558" op amps were popular and became
second-sourced soon by other vendors one of which, as I recall, called
theirs "5558" to conform to the firm's product numbering. None of these
products was the RC4558, a later design with PNP input stage. (Motorola
itself then proceeded itself to second-source the RC4558 too.) In 1974 (not
1973) I put a circuit in _Popular Electronics_ calling for a "558-type" dual
op amp, intending a 1558 or one of its second-sourced, slightly
different-numbered versions. This yielded a file of correspondence to me in
California from hobbyists as distant as Selangor, Malaysia (I just checked
the file) full of requests for clarification on the "558" part number, an
issue haunting me still, as you see. :-(

- it is of quite *different* design to the uA741 (released
in 1968) or MC1458 (a dual 741).

Regarding comparisons to 741, Mr Allison employs a close-up lens, mine is a
zoom. In the context of the popular Philbrick K2-W and K2-XA vacuum-tube
DC-coupled op amps (still in use! _mirabile dictu_), the many successful
solid-state pre-monolithic op amps including the breakthrough Philbrick P2
and P65, low-cost Nexus SQ10A, several from NV Philips; early monolithic
generations of low-voltage three-stage, then high-voltage three-stage, then
high-voltage two-stage designs (Fullagar's 741, Widlar's LM101), the duals
we are discussing, the low-cost National "quad 741" (Fredrickson's LM324),
Lovelace's NE5532, Huijsing ("Professor Op Amp")'s NE5534, the mixed-process
op amps of the middle 1970s, and many others, it's possible to observe in
the RC4558a bipolar design with mirror-loaded input stage, NPN Darlington
second gain stage, complementary emitter-follower output stage, and internal
single-pole minor-loop frequency compensation (popularized by the Philbrick
K2 family, not the much later 741 as the young engineers suppose). It is
possible to find designs that are indeed nearer to the original 741, but not
many -- which is why some people would call it a 741-class design. (It also
has the internal fixed unity-gain freq compensation decried as a limitation
in Jim Roberge's classic op-amp design text -- I cited the result, a
performance limitation apt to yield audible distortion.) I have some
experience designing monolithic op amps (one-, two-, and three-gain-stage
types, bipolar and MOS, some fast, some low-noise, some just weird) so maybe
I lump more designs into the "741 class" than the next person might choose
to do.

If anyone would like to really learn about op amps and their ways, from a
long focus, one of the Primary Sources that taught the world about op amps,
the 1965 Philbrick Applications Manual, is now online, thanks in part I
believe to one of its authors (Dan Sheingold). The current link is

http://www.analog.com/library/analog...mplifiers.html

-- be sure to re-assemble and paste into your browser, if the line gets
wrapped to more than one.

Again I hope this will find some use to someone, and apologize for still
mixing "558" part numbers after thirty years. -- Max Hauser

"Phil Allison" in ...

"Max Hauser" wrote:

** The RC4558 was *introduced * in 1974 by Raytheon

Sorry! I screwed up there, forgetting the actual RC4558 (and the focus of
this thread) in the haunting maze of other and more common dual op amps of
at least three distinct designs all called some kind of -558, as follows (if
you're interested). It was not the RC4558 I referred to in the previous
posting. More on op amps in general at the end, and a glorious historical
link.

Some history. The original, Motorola MC1558, was explicitly a dual 741.
Its significance was partly 8-pin package, unlike earlier Fairchild and
National 14-pin dual-741 types. (I also remember an early dual 741 from
Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s
so don't hold me to precision there.) The MC1558 was supplemented by
Motorola's high-speed version (MC1558S) as Jim Thompson, working there at
the time, recalled recently, 22-Feb-04 in sci.electronics.design -- the
second distinct circuit. These early "558" op amps were popular and became
second-sourced soon by other vendors one of which, as I recall, called
theirs "5558" to conform to the firm's product numbering. None of these
products was the RC4558, a later design with PNP input stage. (Motorola
itself then proceeded itself to second-source the RC4558 too.) In 1974 (not
1973) I put a circuit in _Popular Electronics_ calling for a "558-type" dual
op amp, intending a 1558 or one of its second-sourced, slightly
different-numbered versions. This yielded a file of correspondence to me in
California from hobbyists as distant as Selangor, Malaysia (I just checked
the file) full of requests for clarification on the "558" part number, an
issue haunting me still, as you see. :-(

- it is of quite *different* design to the uA741 (released
in 1968) or MC1458 (a dual 741).

Regarding comparisons to 741, Mr Allison employs a close-up lens, mine is a
zoom. In the context of the popular Philbrick K2-W and K2-XA vacuum-tube
DC-coupled op amps (still in use! _mirabile dictu_), the many successful
solid-state pre-monolithic op amps including the breakthrough Philbrick P2
and P65, low-cost Nexus SQ10A, several from NV Philips; early monolithic
generations of low-voltage three-stage, then high-voltage three-stage, then
high-voltage two-stage designs (Fullagar's 741, Widlar's LM101), the duals
we are discussing, the low-cost National "quad 741" (Fredrickson's LM324),
Lovelace's NE5532, Huijsing ("Professor Op Amp")'s NE5534, the mixed-process
op amps of the middle 1970s, and many others, it's possible to observe in
the RC4558a bipolar design with mirror-loaded input stage, NPN Darlington
second gain stage, complementary emitter-follower output stage, and internal
single-pole minor-loop frequency compensation (popularized by the Philbrick
K2 family, not the much later 741 as the young engineers suppose). It is
possible to find designs that are indeed nearer to the original 741, but not
many -- which is why some people would call it a 741-class design. (It also
has the internal fixed unity-gain freq compensation decried as a limitation
in Jim Roberge's classic op-amp design text -- I cited the result, a
performance limitation apt to yield audible distortion.) I have some
experience designing monolithic op amps (one-, two-, and three-gain-stage
types, bipolar and MOS, some fast, some low-noise, some just weird) so maybe
I lump more designs into the "741 class" than the next person might choose
to do.

If anyone would like to really learn about op amps and their ways, from a
long focus, one of the Primary Sources that taught the world about op amps,
the 1965 Philbrick Applications Manual, is now online, thanks in part I
believe to one of its authors (Dan Sheingold). The current link is

http://www.analog.com/library/analog...mplifiers.html

-- be sure to re-assemble and paste into your browser, if the line gets
wrapped to more than one.

Again I hope this will find some use to someone, and apologize for still
mixing "558" part numbers after thirty years. -- Max Hauser