Are any of those IC usable in guitar circuits ?

[Gil]

Took them out of an old Viscount organ...

LM358N
LM358M
LM358P
LM3080N
LM324N
M74HCI388I
MN74C14N CD40106BCN
UA741CP

[Peter Snowberg]

Hi Gil, Here is by biased view:  :shock:

UA741CP - Low quality single op-amp - Not worth the trouble. Try TL071 instead.

LM324N - Low quality quad single rail op-amp - Not worth the trouble. Try TL074 instead.

LM358N - dual version of LM324 - Not worth the trouble. Try TL072 instead.
LM358M - dual version of LM324 - Not worth the trouble. Try TL072 instead.
LM358P  - dual version of LM324 - Not worth the trouble. Try TL072 instead.

MN74C14N - Hex Schmidt Inverter - Good logic chip, not not too useful for guitar.
CD40106BCN - Hex Schmidt Inverter - Same chip as above - different numbering system

M74HCI388I - I have no idea what this one is. I have never seen an 'HCI' logic family & and the 388 part number is very obscure.

LM3080N - Output Transconductance Amp (OTA) - Cool chip for some compressors. This one is worth using.


If you use any of the op-amps in a circuit, I would advise using a socket so you can swap them out for better chips.

Sorry to rain on your parade.

-Peter

[mattv]

I don't have a opinions on the op-amps, though you can use them in many instances.

I'd take one of those hex inverters and make Tim Escobedo's PWM. It's neat.

[Jay Doyle]

I don't know, I like a lot of the old opamps like the 741 for their limitations and unperfectness compared to the newer ones.

I really like the way a 741 distorts and limits the upper hash. It was good enough for the Dist+! I even have an old 709, the first, that I think sounds good when distorting.

Worth keeping around.

[Gil]

Thanks !

I actually have these ones as well -

M112B1
TMX3639NL
M5450B7
M2764AFI
SN74LS377N
HCF4053BE
SN74HC138N
HEF40518P

What about these ones ?

[The Tone God]

I don't total agree with the some of those statements. The 741 is still a fun opamp to use for audio. Many older circuits use it so for die hard purists this would be a nice find. 324s are still useful in some applications (including audio) and in some cases better then the TL0XX ICs. Don't worship at the TL0XX alter all the time.

The MN74C14N and CD40106BCN are NOT the same IC. If they were they would not have different names. They are both schmitt Hex inverters but the 74C doesn't run on as wide a voltage range. It also takes more current. While these difference are minor there are other differences but I won't get into it here.

Its not a bad fnd with some parts that could be useful for playing around.

Andrew

[jsleep]

Hi Gil,

In the right circuit LM741 can generate some cool distortion.  As you know not all opamps in all stompbox circuits are in the audio signal, sometimes outside the audio path, the junky opamp ICs work just as well as the high end opamps.  Just my 2 cents.

JD

[Joep]

I always use low-quality part like the 741 and the 1458, to test my circuit. If everything works fine, you can replace the part, with beter ones....if you like off course

[Ge_Whiz]

M112 is a keyboard master divider - generates an octave of semitones from one master frequency, which can then be fed to 'divide-by-two' circuits to produce the lower octaves. If you adjust the input frequency up or down, all the notes are adjusted to remain in step.

[The Tone God]

SN74LS377N - D Flip flop
HCF4053BE - Multiplexer (My guess)
SN74HC138N - 8 Line Decoder/DeMultiplexer
M5450B7 - Display Driver (My Guess)

Andrew

[Peter Snowberg]

Tone God makes a good point. High quality parts do not always equal high quality effects. If you are building a distortion, the whole object is to clobber the signal anyway so there are no rules. Follow your ears. Just don't expect vintage parts to be low noise.

 TMX3639NL – I couldn’t find anything but X is often used in production prototype chips so I tried TMS3639 and found this place where that chip is available in six versions for $59.90 each. I’m sure something could be hacked from it but data will be hard to find.
M5450B7 – Maybe a SGS/Thompson 34 LED driver. Cool chip, but no audio use. Could also be a house numbered microcontroller or other LSI part.
M2764AFI – EPROM with either firmware or maybe a wave table. Might work with TMX3639. Follow the traces to find out.
SN74LS377N – Octal latch used with EPROM. No audio use.
HCF4053BE – Triple SPDT switch. Useful for signal routing.
SN74HC138N – 3 to 8 decoder. Digital chip with no audio use.
HEF40518P – I’m guessing 4051BP - SP8T switch. Not as useful as the 4053.

Andrew, you are very right about the op-amps but I would have to disagree with your disagreement on the digital logic. There is more than one chip with the same die sold under two or more numbers. The 40xx & 74Cxx series were very popular but the 74xx numbers were far more popular so a few later 40xx parts mimicked 74LS pinouts and were sold as 74C series. If you look at the Fairchild datasheets for the 40106 it says equivalent to the 74C14. The supply voltage and current consumption are the same. The parts are speced a little different (as the families are in general), but they look like they could be the same die to me. The only alter I pray at has a filament.  :wink:

-Peter

[Arn C.]

In the picture of the PWM there is a picture of the LFO to the bottom right.  The pins shown to be used are 12 and 13 of the 40106,  do I use the pins on the same chip or do I have to install another one?
Thanks!
Arn C.

[mattv]

You can use the pins on the same chip.

[Arn C.]

[The Tone God]

Andrew, you are very right about the op-amps but I would have to disagree with your disagreement on the digital logic. There is more than one chip with the same die sold under two or more numbers. The 40xx & 74Cxx series were very popular but the 74xx numbers were far more popular so a few later 40xx parts mimicked 74LS pinouts and were sold as 74C series. If you look at the Fairchild datasheets for the 40106 it says equivalent to the 74C14.

Intersting. The 74XX were more popular at the time since TTL was the common logic being used. When CMOS came along the 74C family were the CMOS adapated versions of the TTL stuff so desginers could still feel comfortable. They are VERY close to each other but there are differences. When I look at the spec sheets from other companies (Motorla, National, Texas Instruments, etc.) they do state differences. I guess Fairchild decided to use the same die for both IC families. Thanks for pointing that out.

The only alter I pray at has a filament.  :wink:

LOL, I like that. Its almost sig worthy.

Andrew

[Peter Snowberg]

Thanks. That brings up an interesting point...

The difference between 4558 makes is well known, but is there a similar thing here?

Are the variations between logic chips enough to make a decernable difference in inverter distortion circuits? I would guess yess. Also, can you use a feedback resistor to push a schmidt inverter into a pseudo linear region with any audio use?

Gil, you may have to build some distortion boxes to clear this up.  

Take care,
-Peter

[The Tone God]

That is an intersting point. I would guess that different ICs do sound different.

I have thought about playing around with digital distortion using different ICs and techniques. Schmitt and non-schmitt triggers, biasing the gates differently, starving the power supply, etc. It would be a fun experiment.

Andrew