+/-15Vout opamp for gain stage

[anli]

Can anybody suggest an opamp wich:

- is known to work well as gain amplifier at +/- 15V output voltage
(i.e. with declared parameters at high output voltage)
- may be used with +/-30V power supplier
- is widly tested subjectively (with ears :-) and proved to be excellent
in aufio DIY-ing.

And I'll be happy if opamp's output stage works in Class A, are such opamps there?

Thanks in advanced!
Andrew

[Mr Evil]

I tend to use OPA445 for higher voltages. I've always been very pleased with its performance. Works up to +/-45V rails.

I'm fairly sure there is no such thing as a class-A op-amp. I don't think there would be a big enough market for such a thing except amongst the most enthusiatic of enthusiasts.

[anli]

I have not heared about Class A opamps too :-)

OK, I have looked at OPA445 price in my region and it is not very sutable ($30).
If we eliminate +/-30V PS, and leave +/-12V output amplitude - will such
elimination give us more choices? It isn't difficult to supply needed PS,
but output amplitude is important at any case.

[Mr Evil]

$30? Ouch. It's only £5 (~$10) here.

Most op-amps can reach within ~3V of the supply rails, so to get +/-15V (assuming that was peak voltage you wanted) you could get away with +/-18V supplies, which would widen your choices a lot. Rail-to-rail op-amps could do it with only +/-15V supplies, and there are plenty of that sort of op-amp around, although they might not be the best for audio (I've never used any for audio).

[digi01]

Here is my gain stage & headamp,it is based on a dual LM6172 with solid class B (AB) driver.

LM6172 DATA SHEET

the transistor pairs that I used is B647/D667.
B647 DATA

some helpful discuss on headwize.
URL

inner pic attached,

[anli]

I see, Vout _may be_ about PS, but the problem is, I think, opamps work
worse when Vout is near to PS. At least, "discrete opamps" are very
sensitive in their parameters when Vout is near to PS.

[JoeBob]

I think the OPA604 can be run of relatively high voltages (for an opamp), +/-24V if I do recall correctly. Admitedly this is absolute max, but I've been running at 2604 at +/-24V for a rather long time now and it's still going strong. Even the NE5532 can be run of higher than +/- 15V supplies.

It can be argued if the OPA604 is excellent for audio or not, but alot of people like it's sound.

Admitedly these are not +/-30V rail to rail opamps, but hopefully they're more usefull to you than the +/-15V that is ever so common.

[Elso Kwak]

Originally posted by anli
Can anybody suggest an opamp wich:

- is known to work well as gain amplifier at +/- 15V output voltage
(i.e. with declared parameters at high output voltage)
- may be used with +/-30V power supplier
- is widly tested subjectively (with ears :-) and proved to be excellent
in aufio DIY-ing.

And I'll be happy if opamp's output stage works in Class A, are such opamps there?

Thanks in advanced!
Andrew

Hi Andrew,
What is your circuit or application?

[anli]

Originally posted by Elso Kwak


Hi Andrew,
What is your circuit or application?

There isn't final design. I serach/investigate amplifiers with Class-A
output stage. At any case - with or without global NFB, some gain
stage (and balanced line driver) must exist, and I do no reject opamps
using in these stages, but do it for an output stage only :-) So, opams as
gain_stage/balanced_driver pros and cons are interesting for me.

[anli]

Originally posted by JoeBob
I think the OPA604 can be run ...

Thanks, I'll look at OPA604 .

Andrew