4558 and TL072 question

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In a pure world, yes and maybe. NE5532 sounds okay. It strongly depends on what you are replacing the parts in. If it had 4558's, I doubt it rates spending $10.00 or more each on op amps when these maligned op amps (TL072, NE5532) would bring a large improvement.

You would be shocked to see what your audio signal goes through in a studio. Sometimes an NE5532 is the best thing in the chain. The most common interconnect is Beldin wire. Older consoles are chock full of old electrolytics (new if you are lucky) and older transistor designs. I'm thinking of old Neve and MCI boards. These are prized by some for their sound. Yes, tube and transistor outboard gear. Bucket brigade echo boxes, or if you're real lucky, an older tape loop job. :eek:
The newer boards like the SSL may be all digital. 'nough said. Then we compress it. Compression probably happened early on actually:tons:

Now, there are some that think op amps are a waste of time & money. Everyone has a point of reference, and the truth is often ugly.

-Chris
 
I replaced the 4558's in my cheaper Sony 50+1 disc changer (CDP-CX50) with TL082's,figured it couldn't hurt.
I actually noticed a bit "tighter/faster" bass response,and the treble seemed a bit better too.At first,It seemed to affect the midrange in a strange way,or maybe it was just my ears/brain adjusting?
I wasn't sure if I liked it at first,but it seems okay,since the 82's are still in there. ;)
I also added small bypass caps on all the filter caps for each rail,and added a couple Sanyo Os-Con's to bump up the capacitance a tad..sounds pretty good for a cheaper player....Still havn't removed the muting x-istors yet either..I plan to replace them with a small relay. ;)
 
Chris,

Why would anyone PAY for op-amps? I haven't purchased an
op-amp in since the early '70s.

I'm fully aware of what audio signals go through. That's no
reason for poor design on the part of a DIY'er.

And no, I'm not into exotic op-amps for their own sake. But
surely anyone doing a DIY mod can do better than TL072
or 4558, even for less than $10, even less than $2
 
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Hi Upupa Epops,
I agree with you. I was commenting really on equipment in use in different studios in the eighties & nineties, maybe still.
Anyhow, I was trying to get the advice back on track to the original post. Inject a little realism. Many updates are valid considering the situation, even though the upgrade can be taken further. It isn't a perfect world and never will be.
-Chris
 
strongly depends on application. 4558 is slow, but quite low noise, especially at low input impedances (works satisfactory as mic preamp, for instance, or playback head preamp). tl072 is faster and better suited for higher input/output voltages. good as driver for line amp or headphone amp with a pair of comp. transistors. these are just examples. they are 100% compatible in terms of pin layout, supply requirements, etc... anyway, guys there are true, they are both pretty poor stuff, if real high end is concerned.
 
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Hi kexik,
Yes, using the correct family of parts, in this case bipolar or J fet inputs. By looking at the application you are engaging in cost accounting by not choosing a part that is not overboard. That's the balance that should be achived. Building to a price can skew this.

-Chris
 
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