That was to be hoped. Plenty of home hi-fi manufacturers have implemented single-stage RIAAs using 4558s that in general tend to be perfectly serviceable. A standard active RIAA requires a GBW of no more than about 200 kHz, there's no other way it would even have worked using just two vacuum tubes or transistors per channel.
Agreed. You can kinda-sorta make it work by applying several mA of class A bias to the output stage, at which point it's "just" very noisy.
Actually you can even find two different LM833s, the other one is the "N" part. One of them is the NatSemi part using a complementary output stage (with one side being pretty weak in terms of current), the other one is TI's rebrand of their MC33078 with the quasicomp output stage.
I think so, I've tried both in RIAA amps (not single stage, at least two stages).
The MC33078 is easier to work with, it's not quite so temperamental as the LM833.
One rule for the LM833: never -ever present it with a capacitive load.
And one for the MC33078: don't load it hard, keep load below 10mA, or better still 5mA.
Finally, they are cheap, around 0.8$.
Have a nice day
The MC33078 is easier to work with, it's not quite so temperamental as the LM833.
One rule for the LM833: never -ever present it with a capacitive load.
And one for the MC33078: don't load it hard, keep load below 10mA, or better still 5mA.
Finally, they are cheap, around 0.8$.
Have a nice day
See this about the MC33078
http://www.diyaudio.com/forums/analog-line-level/294165-opamp-survey.html
I'm using ST33078 and I'm very happy with the sound. Newark listed them as "low noise" and had them on sale at $.37 for dip package. I'm using one for RIAA 50x gain on mm cartridge, the next after the mixer resistors to drive a 4 m RCA plug cable. Very much quieter hiss than NJM4558 at 50x gain. Sounds better than my PAS2 preamp at this point.
The 33078 slew rate is so fast, I had to install a .1 uf capacitor between the PS rails between the two packages, and a 33 pf disk capacitor around each feedback resistor. Before that it was oscillating at ~1 mhz. The mixer didn't need those using 4558. Also, hum was supressed by putting a 330 ohm resistor between e-cap and 4558 op amps. I took that out and went to a triple pi filter with wall transformer outside the steel case, to get rid of the hum.
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4558 OP amp
Recently I Re Caped My Bose 901 Series IV Equalizer because of a non Sounding Channel. Replaced the Caps With Audio Grade Nichicon Caps and Replaced both the Factory LF353N because one was bad with 4558 . the first thing I notice was that to get a decent bass from my 901's I have to put all the way up the bass slider on the EQ. reading the comments here about the 4558's I think somebody has a better replacement for them. can someone help me make the EQ sound like it should? Thanks
Recently I Re Caped My Bose 901 Series IV Equalizer because of a non Sounding Channel. Replaced the Caps With Audio Grade Nichicon Caps and Replaced both the Factory LF353N because one was bad with 4558 . the first thing I notice was that to get a decent bass from my 901's I have to put all the way up the bass slider on the EQ. reading the comments here about the 4558's I think somebody has a better replacement for them. can someone help me make the EQ sound like it should? Thanks
Sorry LF353 and 4558 are not interchangeable, one is fet and one is bipolar. Totally inappropriate choice. The Bose EQ was designed for the much higher input impedances of the LF353. You could try OPA2132 or OPA2134 either of which would be much better choices. (Even TL072 or one of its more modern cousins would be a better choice.)
There's no "real problem" for the LF353N. National was bought out by T.I. a while back. This is old news.
Just wait until Mouser gets more stock on T.I.'s version of the National LF353 and purchase all your heart desires if it's something you want to try.
http://www.mouser.com/ProductDetail...GAEpiMZZMtCHixnSjNA6JlKxGj6zye%2bZF/y0ICs1BI=
SQ of the LF353N(dual) and the LF356N(single) are fair at best.
I kinda like the LF356 actually. While it's a typical '70s FET input part in a number of respects and does not cope with high signal levels as well as even a TL071, its output stage seems to be run fairly hot and delivers good results under load (including capacitive loading) as long as its - still relatively modest - output current limits are not exceeded. When you look at Samuel Groner's data, you will find that its distortion levels at 0 dBu into 600 ohms still beat quite a number of more recent parts.
What I really like about the LF35x is that ther can be driven beyond the rails (as long as the resulting input current is limited) with no damage or degradation. When used as an input stage of a 1000+ watt PA amp you often need that. Especially during development, where you might put out full 100 volt rail voltage back to the inverting input. With "better" op amps you kiss it goodbye, with the 356 you fix the fault and keep right on trucking. And it will cope with drunken idiot treatment without having to resort to back to back zeners or risk D.C. To the speaker when you *really * don't want it to happen.
They also have a particular "sound" that I happen to like. Even better when the output is forced into class A or driving a (class A) emitter follower inside the feedback.
They also have a particular "sound" that I happen to like. Even better when the output is forced into class A or driving a (class A) emitter follower inside the feedback.
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