op amps for a preamp

[nhuwar]

Ok when I was in high a guy my dad worked with gave me a audio related stuff he used to build amps and pre's in high school.

Well to make a long store short Ive got all these opamps and I was wondering , folishly mind you that He gave me some old school diamond in the ruff.
Ok here goes they are as follows

mc1302l
u5b 7741312
rm741t
These are the ones

Thanks Nick

[lineup]

Originally posted by nhuwar

mc1302l
u5b 7741312
rm741t
These are the ones

Thanks Nick

MC1302 I can't find. There is an Radio Receiver Circuit MC13020.
U5B7741312 Single General Purpose Op Amp Intersil Corporation
RM741 Single General Purpose Op Amp Raytheon Fairchild


I used this good link http://www.datasheetarchive.com/
to find datasheets and details for your chips
'741' is a very old and classic op-amp
but today we do not use it for Audio.
It can be used for other things alright, but for audio ... no!

U5B7741312
I don't know much about.
But I guess it is nothing specially good for a preamp.

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

Advice:
Buy yourself a few good modern op-amps.
Most anything will give a better result than using those old ones.
They do not have to cost much.

If you want to play it very cheap, buy:
NE5534 (single amp), NE5532 (dual, stereo in one chip), TL071 (single), TL072 (dual).

If you need only a few pieces you can try some better AUDIO op-amps.
They won't ruin you of your money:
OPA2134 (dual), OPA227 (single), OPA2227 (dual)

[nhuwar]

well thanks for the input I think I'll stick with the old standard and go with a precision burr brown opamp.
Just have to pick one.
thanks

[nhuwar]

any suggestions

[Minion]

What type of Impedances are you going to be working with???

For High Impedance Inputs the OPA134/2134 is a very good fet opamp (burr brown) for Lower input impedances something like the OPA604/2604 is a very good chip.....

I guess it depends on what you are going to use them for....

[unclejed613]

the Apt-Holman preamp used TL072's, and it was a really good preamp.

the intersil and the 741 amps are probably good for dc control use like voltage regulators, DACs, LED drivers, etc...

the mc1302 is probably a MOT replacement for the LM302 voltage follower/buffer amp. the datasheet is available here:
http://www.datasheetcatalog.com/data.../0/LM302.shtml

[nhuwar]

normal low level high impedence input for a preamp correct me if i'm wrong but isn't the standard for most stereo equipment 15k

[unclejed613]

usually between 10 and 20k.... there was an article in Audio DesignLine recently about audio equipment I/O impedances, and unlike older equipment that had a 600 ohm impedance standard, modern equipment goes for voltage matching rather than impedance matching..... "line level" is usually anywhere bettween .5Vrms and 1.5Vrms depending on the manufacturer......

600 ohms is still used for balanced mic inputs, and phono cartridges vary between 1k and 10k

[nhuwar]

This is where my knowledge grows thin and I need help. For 1 I'm not sure if I want to go dig or analog I veer toward ana because I know it from my rf knowledge. I've got abit of dig adc's & dsp chips & I lnow I have more options in dig.

I't just going to be a learning exp. the chips i have are ti and b.b. you know free sample are great.
The question I have is do most of you etch your own boards or do you order them and if so you use something like eagle pcd or something else.

[Minion]

Originally posted by nhuwar

I't just going to be a learning exp. the chips i have are ti and b.b. you know free sample are great.
The question I have is do most of you etch your own boards or do you order them and if so you use something like eagle pcd or something else.

Well I don"t know about the rest of everybody but I personally have never used a Non-Home etched Board...
I design and etch all of my PCB"s (actually design about 90% but etch 100% of all of my boards) as I usually only make one or 2 Boards of each design so it would be very cost prohibitive to get pro quality boards made for a one or 2 off board.....

I get really good deals on Blank PCB material (about 5 square feet for $20) and use the toner transfer method so it costs next to nothing to make a Board.....


CHeers