opa 2134
Dear Sir,
an improved version ( better slew rate ) exists : OPA 2604
This opamp sounds warm despite his high dynamic !!!
regards
Rock
Dear Sir,
an improved version ( better slew rate ) exists : OPA 2604
This opamp sounds warm despite his high dynamic !!!
regards
Rock
motherone said:
Perfect opamp (AD8066), the best mentioned here. But hell it is so sensitive to pure capacitive loading! Even 10 pF is too much. Small resistor in series with ouput, like 10 Ohm, solves this problem.
Hi,
single to dual opamp adaptors?
Where, in UK, are they available? At what target price?
The original thread starter stated opa2134. This is a dual of the 134. That's our starter's specification.
single to dual opamp adaptors?
Where, in UK, are they available? At what target price?
The original thread starter stated opa2134. This is a dual of the 134. That's our starter's specification.
Upupa Epops said:
The funny thing then is that this op amp has a special and very intricate distorsion reduction circuitry that no other op amp has, as far as I know. Maybe it creates a strange distorsion behaviour that measures well but sounds bad?
Try the AD823, an FET dual that will drop right in for the OPA2134/2604.
About $5 in one lot quantity.
About $5 in one lot quantity.
Re OPA2604
"The funny thing then is that this op amp has a special and very intricate distorsion reduction circuitry that no other op amp has, as far as I know. Maybe it creates a strange distorsion behaviour that measures well but sounds bad?"
According to Self's tests, the distortion is in fact fairly high! But I've lived with this op-amp for some time, and honestly its not a bad sounding design, IMHO.
Haven't had a chance to test the 8066 nor any from Analog Devices, no dealer where I live... :-(
Cheers!
"The funny thing then is that this op amp has a special and very intricate distorsion reduction circuitry that no other op amp has, as far as I know. Maybe it creates a strange distorsion behaviour that measures well but sounds bad?"
According to Self's tests, the distortion is in fact fairly high! But I've lived with this op-amp for some time, and honestly its not a bad sounding design, IMHO.
Haven't had a chance to test the 8066 nor any from Analog Devices, no dealer where I live... :-(
Cheers!
AndrewT said:
Surely some in the UK sells Browndog adaptors and are very cheap, A$9 and we get ripped off in Oz.
http://www.soundlabsgroup.com.au/browndog/browndog_single_dual_opamp_dip.htm
Of all the op amps I've used, I still preferred the sound of the OPA2134 and very easy to work with. I just didn't like the sound of the OPA627 even after going through immense care to set them up properly regarding layout, by-passing and power supply..... one of those things.
rabbitz said:
I agree. The OPA2134 can sound positively lovely as long as you keep the load impedance resistive and above a few K. The 8066 gives a more detailed presentation but can sound a bit course, particularly if you've lived with the silkiness and sweetness of the 2134 for a while. Personally this is my favourite op-amp. I recently changed out the 5532s in my MF XDACv3 with 2134s, so they're used for I - V and bal - unbal converting. The improvement was huge.
🙂
Here is the idea I’m working at:
A single end power amplifier with a volume control on the input. I use the two OP for the input stage, one as a buffer and the second as VAS.
Then I would like to take the VAS output directly to the Current stage.
This have an ordinary emitter follower and working against a current source.
I’m lifting the signal so the whole one is on the positive side of the ground. Then I don’t need to have any cap on the output.
I’m going to use battery supply for +/- 12V.
Please give me some hints on this.
A single end power amplifier with a volume control on the input. I use the two OP for the input stage, one as a buffer and the second as VAS.
Then I would like to take the VAS output directly to the Current stage.
This have an ordinary emitter follower and working against a current source.
I’m lifting the signal so the whole one is on the positive side of the ground. Then I don’t need to have any cap on the output.
I’m going to use battery supply for +/- 12V.
Please give me some hints on this.
Attachments
David Lewis said:
The OPA2134s don't seem to be a good choice for IV conversion given their rather poor looking large-signal pulse response, wouldn't it be an improvement to get a more accurate and fast op-amp to do it? Comments invited here, since I am planning to swap out a couple of JRC op-amps in a multi-format player for some 'nicer' op amps.
As bal to unbalanced and post DAC filters they should be pretty good - that's certainly how they are used in commercial dvd and cd players. And I definitely agree that they do sound better than the 5532s!!
Cheers
Clem
anything better than opa2134
Hi,
Interesting that no one has mentined opa2132P so far. It is a touch better than opa2134 - especially where small reduction in noise level is welcomed. The final choice of ICs depends on application and personal preferences.
Personally I like opa637bp (esp. biased into A class - non inductive resistor will do) but it's an overkill in most applications and of course gain of 5 imposes some further limitations as well.
op275 and opa2604 are OK if one needs large signal headroom - PS > +/-20V.
cheers,
Hi,
Interesting that no one has mentined opa2132P so far. It is a touch better than opa2134 - especially where small reduction in noise level is welcomed. The final choice of ICs depends on application and personal preferences.
Personally I like opa637bp (esp. biased into A class - non inductive resistor will do) but it's an overkill in most applications and of course gain of 5 imposes some further limitations as well.
op275 and opa2604 are OK if one needs large signal headroom - PS > +/-20V.
cheers,
Hi janusz,
Looking at the data sheet of the 2132 vs 2134, it would seem that the noise curves are identical. In fact just about every spec is, save for a higher Ibmax for the 2134, though I could have missed something!
Pricewise the 2132 is higher, so I have to agree there may be something the data sheet isn't saying!
Cheers!
Clem
Looking at the data sheet of the 2132 vs 2134, it would seem that the noise curves are identical. In fact just about every spec is, save for a higher Ibmax for the 2134, though I could have missed something!
Pricewise the 2132 is higher, so I have to agree there may be something the data sheet isn't saying!
Cheers!
Clem
The 2132 seems not very common amongst DIYers, but interestingly, Sony has used it in SACD players. There must be some reason why they choose that particular op amp when they depart from the usual japanese ones.
You're right, the DVP-9000ES uses OPA2132s for post-DA work.
On the other hand, Sony's X777ES and XCD1 (their highest-end SACD units), used a combination of ICs: LM6172MX for I-V, followed by OPA2132s for balanced to unbalanced conversion, going into an FDNR filter stage using OPA2604s (? - schematic lists these as LM6172, but people on the net say 2604), then into AD712 as a line amplifier, followed by a discrete complementary transistor output buffer stage!
Seems like Sony wanted to cover all bases here!
Cheers
Clem
On the other hand, Sony's X777ES and XCD1 (their highest-end SACD units), used a combination of ICs: LM6172MX for I-V, followed by OPA2132s for balanced to unbalanced conversion, going into an FDNR filter stage using OPA2604s (? - schematic lists these as LM6172, but people on the net say 2604), then into AD712 as a line amplifier, followed by a discrete complementary transistor output buffer stage!
Seems like Sony wanted to cover all bases here!
Cheers
Clem
The model I was thinking of was the SCD555ES. It uses 2132 for I/V followed by an active LP filter using 6172 and then there are 2132 again.
THS4032
Try the THS4032 from TI and be amazed.
My OPA627 are collecting dust now.
LT1360 of Linear Technology is also better than OPA627.
But some like it warm.😀
Klaus
Try the THS4032 from TI and be amazed.
My OPA627 are collecting dust now.
LT1360 of Linear Technology is also better than OPA627.
But some like it warm.😀
Klaus
Re: THS4032
The THS4032 has some nice specs!!!
Isn't it difficult to use them in an UCD Class D amp?
Radian said:
The THS4032 has some nice specs!!!
Isn't it difficult to use them in an UCD Class D amp?
Thanks for the tip on the THS4032!
Looks like a good candidate for I-V conversion - very high speed, very clean pulse response.
Cheers!
Clem
Looks like a good candidate for I-V conversion - very high speed, very clean pulse response.
Cheers!
Clem
anything better than opa2134?
Hi Clem and all,
Data sheets do not tell all the story. My comments came from a couple of articles I read some time ago. Authors compared the in circuit performance (typical inverted and non-inverted mode) of a number of ICs and opa132p/2132p appeared to have an edge in a few areas over quite a few other ICs which looked better on paper. I thing noise was one of these for the P version but my memory may be playing trics on me. Differences were not huge but notable. Similarly, Duglas Self argued that his favoured but ancient NE5534/5532 performs better in real circuits than many much newer designs with notably better data sheet specs.
I remember not so old times when opa604/2604s were highly praised while now they're being gradualy discarded as being not so good and are replaced by ICs, which are often not much younger. Interestingly - just to expand the list of manufactures doing that - NAD also decided to upgrade its C541i last year by releasing 542 and replacing, among other things, opa2604s with opa2132s.
I used almost all of the mentioned here ICs (except opa627 - but I heard it - and new fast and low noise ADs like 8066/66 and ad8620). My experience tells me that all these ICs when properly used and applied (circuit design and board layout) and surrounded by quality components are extremely difficult to tell apart and in blind ABC tests most people over 30-35 including some musicians (although these guys are much better at picking up differences) can't tell the difference when listenning throuh speakers.
Anyone curious enough to verify that may build a couple of simple test sets consisting of a buffer followed by a good volume pot followed by gain 3 stage (sockets for ICs so thes can be easily changed) and having collected enough friends of all ages at his/her place to make the test statistically significant may find out.
cheers,
Hi Clem and all,
Data sheets do not tell all the story. My comments came from a couple of articles I read some time ago. Authors compared the in circuit performance (typical inverted and non-inverted mode) of a number of ICs and opa132p/2132p appeared to have an edge in a few areas over quite a few other ICs which looked better on paper. I thing noise was one of these for the P version but my memory may be playing trics on me. Differences were not huge but notable. Similarly, Duglas Self argued that his favoured but ancient NE5534/5532 performs better in real circuits than many much newer designs with notably better data sheet specs.
I remember not so old times when opa604/2604s were highly praised while now they're being gradualy discarded as being not so good and are replaced by ICs, which are often not much younger. Interestingly - just to expand the list of manufactures doing that - NAD also decided to upgrade its C541i last year by releasing 542 and replacing, among other things, opa2604s with opa2132s.
I used almost all of the mentioned here ICs (except opa627 - but I heard it - and new fast and low noise ADs like 8066/66 and ad8620). My experience tells me that all these ICs when properly used and applied (circuit design and board layout) and surrounded by quality components are extremely difficult to tell apart and in blind ABC tests most people over 30-35 including some musicians (although these guys are much better at picking up differences) can't tell the difference when listenning throuh speakers.
Anyone curious enough to verify that may build a couple of simple test sets consisting of a buffer followed by a good volume pot followed by gain 3 stage (sockets for ICs so thes can be easily changed) and having collected enough friends of all ages at his/her place to make the test statistically significant may find out.
cheers,
- Status
- Not open for further replies.