Yup, often CD players have a gradual upper treble roll-off... I guess this is often preferable to a very strong digital filtering, in terms of impulse response. Right? Or something like that
Yup, often CD players have a gradual upper treble roll-off... I guess this is often preferable to a very strong digital filtering, in terms of impulse response. Right? Or something like that
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I don't know about a gradual roll off. If it's designed into the player then it's not related to the action of the filters as such (I think you are talking of perhaps 0.5db down at 20 khz at most).
A gradual roll of while inaudible at a single frequency can (possibly) be audible as it reduces the whole spectrum of energy at hf, but it's very slight. Drawing the curtains makes far more difference
If you replace the opamps in a player with 741's that 1 khz squarewave looks essentially the same.
Yeah...and it's always a square wave. That's one of the measurements I never look at (in magazines).Just for interest on "how things sound" that shot of the 1 khz from a cd player.
It doesn't matter whether the player is a 10 £€€$ portable or a 10000 £€$ one... it looks the same. They don't (hopefully) sound the same though.
Have you tried (seriously) the TLO71 in your listening tests
I used the TL072 years ago... I remember preferring the NE5532 at that time.
Have you tried the TLE2071/2072/2081/2082 ? These are the newer, improved (and faster) versions of the TL07x and TL08x. The TLE2082 sounds quite nice, while the TLE2072 it too cold tonally. They're nothing to write home about, though.
Edit: And the TLE2062 with its about 80 mA of output current is quite good for cmoy headphone amps
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I found the TL072 (and 71) a pretty good performer, exceptionally so when price considered. It was the first opamp change I did on my Micromega Stage 2 which had NE5534's and gave that "small" but indefinable worthwhile improvement.
Have since come to like the OPA604AP... I just like the sound... and it works well in the Stage 2 as the I/V convertor with an AD845 as the filter/buffer.
Haven't tried the ones you mention
Would like to try the OPA1611 and 1612 sometime... see they (OPA1611) doesn't have the offest null pins connected... which are used in the Micromega... you can trim the output to 0.000000 vdc or near offer
It's an interesting subject with no right and wrong answers... it's what works for you and what works in your particular application as much as anything.
Have since come to like the OPA604AP... I just like the sound... and it works well in the Stage 2 as the I/V convertor with an AD845 as the filter/buffer.
Haven't tried the ones you mention
Would like to try the OPA1611 and 1612 sometime... see they (OPA1611) doesn't have the offest null pins connected... which are used in the Micromega... you can trim the output to 0.000000 vdc
or near offer It's an interesting subject with no right and wrong answers... it's what works for you and what works in your particular application as much as anything.
Yeah, well, anything audio is like that. No surprise it's so with opamps
Then again, we have to make some use of these public boards, no?
Anyway, I believe that the findings of one can be shared with others to some extent. I'm not a total subjectivist. I'm partly that, and partly an objectivist too
P.S. The OPA2604 sounded good for my ears in a AD1852 DAC I had for a while. And I definitely like the AD845, since it's musical & dynamic...though it's not quite at the level of transparency of LT1028ACN8, OPA1611, and some others.
Then again, we have to make some use of these public boards, no?
Anyway, I believe that the findings of one can be shared with others to some extent. I'm not a total subjectivist. I'm partly that, and partly an objectivist too
P.S. The OPA2604 sounded good for my ears in a AD1852 DAC I had for a while. And I definitely like the AD845, since it's musical & dynamic...though it's not quite at the level of transparency of LT1028ACN8, OPA1611, and some others.
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LME49720 metal case, does sound better than lm4562 in my rotel rcd-855. Will get some OPA1611 to test later.
LME49720 metal case, does sound better than lm4562 in my rotel rcd-855. Will get some OPA1611 to test later.
I really liked the LME49720HA, along with the LME49723 -- funnily, the two opposite extremes of the National line of dual audio opamps, as far as ambition & cost
Instead what's in between I liked not enough... LM4562NA, LME49720NA, LME49860, LME49722...
Next (and last) for me to try is the LME49725, about which I have a good feeling
Right now, I think my absolute favorite is the OPA1611. It simply sounds the most natural, musical, balanced... and crystal clear too...
This morning I've repaired & improved my C&C BOX headphone amp.
Now it's got 2x LME49721 (gain) + 4x AD8532 (buffer). The AD8532 were stock (totalling 1 mA of current output per channel); the LME49721 is a rather new 6V rail-to-rail CMOS opamp that has substituted the stock AD822.
Besides, I've used Rubycon ZLH and YXH capacitors, plus a pair of Nippon Chemicon's (due to size requirements).
Sound is awesome... the LME49721 is a great CMOS audio opamp. There's definitely a better smoothness and solidity to the sound, as compared to my cmoy (even if we're talking of 24V vs. 6V supply voltages).
Now it's got 2x LME49721 (gain) + 4x AD8532 (buffer). The AD8532 were stock (totalling 1 mA of current output per channel); the LME49721 is a rather new 6V rail-to-rail CMOS opamp that has substituted the stock AD822.
Besides, I've used Rubycon ZLH and YXH capacitors, plus a pair of Nippon Chemicon's (due to size requirements).
Sound is awesome... the LME49721 is a great CMOS audio opamp. There's definitely a better smoothness and solidity to the sound, as compared to my cmoy (even if we're talking of 24V vs. 6V supply voltages).
Hi Andrea,
I posted a question to you on this thread:
http://www.diyaudio.com/forums/digital-line-level/156846-so-many-dacs-choose-4.html
Just in case you heaven't bookmarked it. Would you mind to give me some advice?
Thank you!
I posted a question to you on this thread:
http://www.diyaudio.com/forums/digital-line-level/156846-so-many-dacs-choose-4.html
Just in case you heaven't bookmarked it. Would you mind to give me some advice?
Thank you!
Well, to build a MCoy/Grado/PINT/ whatever, for my SR80's, I picked the OPA2228. Think I'll play with that fancy ground reference chip TI makes and 9V lithium's for a PS, with chokes. Kind of a hybrid between all the ideas. This thread has been most helpful. Thanks to all. The goal is for a reference platform where I can listen to changes.
You should!I think I'll get the Poppulse PCM1796 DAC, if I will buy one more DAC
By the way, I got some lt1028cs8 on browndogs and swapped my 4 lt1363 to try a full lt1028 config in the poppulse (4 lt1028cs8 in I/V stage and 2 lt1028acn8 as filter/buffer)
It even better than before!
With 4 lt1363, it was damn clean, but somewhat too clean, lacking some "body" in the mids, and treble extension.
Now, everything is balanced and sounds GOOD!
By the way, lt1028 are used as filter/buffer in the typical schematic for the PCM1792 chip (a bit better one than PCM1796) as you can see here, p35 :
http://focus.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=pcm1792
And they are using a small 33 pF cap between pins 5 and 6 of the lt1028.
I'd like to try this if I can find those caps somewhere...
Nice! I had the feeling that the LT1028 would've been great for I/V conversion too.You should!
By the way, I got some lt1028cs8 on browndogs and swapped my 4 lt1363 to try a full lt1028 config in the poppulse (4 lt1028cs8 in I/V stage and 2 lt1028acn8 as filter/buffer)
It even better than before!
With 4 lt1363, it was damn clean, but somewhat too clean, lacking some "body" in the mids, and treble extension.
Now, everything is balanced and sounds GOOD!
By the way, lt1028 are used as filter/buffer in the typical schematic for the PCM1792 chip (a bit better one than PCM1796) as you can see here, p35 :
http://focus.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=pcm1792
And they are using a small 33 pF cap between pins 5 and 6 of the lt1028.
I'd like to try this if I can find those caps somewhere...
The 33 pF is to compensate the opamp for unity gain...alright, it's an idea.
The LT1028 is my other favorite opamp... besides the OPA1611. I would suggest that you try and combine the LT1028 in I/V, with the OPA1611 for the output buffer. It should be good...
Ouch I read your post too quickly. You used the CS8 for I/V... but that mustn't mean that the twin DIP Browndogs wouldn't fit, right?
I ask because I have 4 LT1028ACN8 on Browndogs ready for use...which might motivate me even further. Then I would manage to compare an optimized V-out DAC to an optimized I-out DAC
I read your post too quickly. You used the CS8 for I/V... but that mustn't mean that the twin DIP Browndogs wouldn't fit, right? I ask because I have 4 LT1028ACN8 on Browndogs ready for use...which might motivate me even further.
Then I would manage to compare an optimized V-out DAC to an optimized I-out DAC Browndogs will fit, I used some for my 4 lt1363. You just need to use them on a socket to stay above the capacitors around the place.Ouch
They must be the less large ones, like those :
Adaptateurs SOIC-DIP - Adaptateur pour AOP 8pin 2xDIP simple vers 1xDIP double
Because the 2 NE5532 were very close to each others....
In fact, they fit better than my dual 1028cs8 adaptors which I had to shorten a little (cutting them like a barbarian...
)I may try to get OPA1611 one day, if I find some cheap, but I'm waiting for some AD797BR first
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