rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
|
Post by rickcr42 on Dec 20, 2006 21:58:30 GMT
you would think so yes but there is more going on in audio electronics than there is in Electronics 101 and that is what gives some of us fits.I can't name the OAs of the top of my head but some sound AWFUL bypassed across the power pins while some sound great. Then there is the add the +/- shunt to ground bypass to the "awful" sounding acrosds the pins amps and it works well for some but still awful for others and in those cases strictly +/- pin shunts to ground and I have no idea WHY scanning a data sheet which method will be the best on pure sonics before actually trying it out with the trying part not always a true indicator either snce a breadboard has a lot of self stray capacitance. would be nice to know what the C/L (capacitance and inductance) combination is that goes with a particular op amp profile and that there IS a parameter i have zero doubt (everything that can be heard can be measured with the trick being to figure out exactly what to measure ). something that I am sure some digging in the electronics library would turn up with the real trick knowing where to look-guessing somewhere in the "moldy files" of the seventies when it seems a lot of what we know now was figured out (solid state anyway )
|
|
|
Post by dc on Jan 15, 2007 16:31:14 GMT
got my LM4562 in the mail (delivered with UPS) arrived in 1 working day completely free of charge!?!? (maybe there is an upside being close to asia)
running in the output section of my Zhaolu 2.0 AD1852 sounds great tbh. better than any other combination of AD823, OPA2604, OPA2111, OPA2107s and a few other wierd opamps that i've thrown in there. looks to be a keeper
|
|
FritzS
Been here a while!
Sound of Blue Danube
Sound of Blue Danube
Posts: 1,364
|
Post by FritzS on Jan 15, 2007 17:10:56 GMT
|
|
FritzS
Been here a while!
Sound of Blue Danube
Sound of Blue Danube
Posts: 1,364
|
Post by FritzS on Jan 26, 2007 16:35:08 GMT
|
|
rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
|
Post by rickcr42 on Jan 27, 2007 2:48:20 GMT
close but not exactly the same The single version has a better input capacitance spec hence a WAY better DC offset,CMMR is a tad worse but at these levels meaningless,output current is a lot less so the dual device a better line driver or unassisted headphone driver,operates with a much lower power supply so the better part for battery operation or as part of a USB powered DAC/Headphone amp or DAC/Line stage maybe and is ever so slightly less noisy though not enough to notice in any real worl app so appears to be,on paper at least,not a true single channel opamp version of the LM4562 but a kissin' cousin,in the same family,has some family traits but not a twin
|
|
FritzS
Been here a while!
Sound of Blue Danube
Sound of Blue Danube
Posts: 1,364
|
Post by FritzS on Jan 28, 2007 11:56:59 GMT
But very close in datas .... I ordered now some LME49710 to test them in my WNA MKII
|
|
rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
|
Post by rickcr42 on Jan 28, 2007 15:22:25 GMT
point being that is no gurantee of sound.Take two amps,both with IDENTICAL specs and you have ?
Two entirely different sounding amps so if the specs vary there is even more chance they will not sound identical.My feeling is they may have the same "house" sound to a degree much like AD differs from BB but will not sound any more alike than say an OPA2134 does to an OPA627 which spec pretty close and have familiar traits but hardly the same chip
|
|
FritzS
Been here a while!
Sound of Blue Danube
Sound of Blue Danube
Posts: 1,364
|
Post by FritzS on Feb 3, 2007 15:10:36 GMT
yesterday I got some LME49710, LM4562 and AD843, AD845 too ........ my WNA MKII (works with AD843) wait for them - LME49710, AD845 but I got my Marantz 7001 KI SACD player and test them - I cannot do all together
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 18, 2007 13:11:14 GMT
Has anyone done a comparison between the LM4562 and the OPA2134 ? The specs seem fairly similar on paper, but in favour of the LM4562. There are some test results on the Douglas Self site, but he doesn't seem to have been able to duplicate the manufacturers test results. BTW, it is not commonly known that many opamps like the OPA2134 , when used as a non inverting buffer (inverting input connected to output) give lower distortion if the s/c is removed and replaced by a resistor of the same value as the input impedance.For example, if the volume control is connected to the buffer stage, set your volume control to your most used listening level position ,and measure the resistance from the wiper to the earth side of the potentiometer. Remove the s/c between inverting input and output pin , and replace with a resistor that is close in value to the measured resistance . In my case it was around 2k ohm for usual CD/DAC listening level . (info from Silicon Chip magazine) Doing this will give the best performance from the buffer stage. SandyK
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 1, 2007 22:56:58 GMT
LM4562 Vs. OPA2134 About 24 hours ago I swapped the OPA2134s in a Silicon Chip designed ( but modded)preamp designed around the OPA2134 , for the LM4562. Initial impressions were of an even bigger soundstage than the 2134 and much more detail.No problems at the bottom end either. They sound much closer in performance to , but not quite as good as my solid state Class A preamp. I must admit, that initially I was a bit overwhelmed by the amount of detail,and perhaps a bit too bright. However,when I played the bonus DVD from "Norah Jones-Not Too Late" deluxe CD, the 48KHZ LPCM sounded VERY good indeed, especially the live studio versions.(after only 4 hours).Currently, I am bedding them in by continuously running since about 14 hours ago. They do seem very promising. SandyK
|
|
|
Post by MrJoshua on Nov 11, 2007 9:09:07 GMT
I've just rolled a couple of LME49710NA into my Keces USB DAC.
First couple of minutes they sounded shite, but after that - W O W - Really detailed and such a wide soundstage!
This is the first time I've ever rolled any OpAmps and I'm really surprised by the difference they've made!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 11, 2007 9:21:38 GMT
Josh The wealth of detail can sometimes be a little overwhelming, and ultimately tiring. Being a VERY fast device, they may have stability problems in some layouts, so results may vary greatly. If they see , for example, a short cable directly at their output, they may even oscillate somewhere between 10 and 30MHZ. They definitely need something like a 100 ohm resistor close to their output pins if driving even a short cable, such as an integrated headphome amplifier on CD/DVD players. SandyK
|
|
mrarroyo
Been here a while!
Our man in Miami!
Posts: 1,003
|
Post by mrarroyo on Nov 11, 2007 14:17:49 GMT
Sandy, have you given a try to LMH6643? I am using them now as buffers w/ an AD8599 in the amp section of my iBasso D1 and the sound is very detailed, clear, extende, w/o sibilance. Plenty of impact also.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 11, 2007 20:04:06 GMT
No, but I will research them now thyou have mentioned that combo.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 12, 2007 4:23:47 GMT
I just now got my Audio Alchemy Headphone Amp v.1 (1996 model) modded by Reference Audio Mods here in the Detroit Michigan area and Doug has installed the LM4562 op amps in this unit. I had the Power Station #3 upgraded as well, and all together, as you would expect, this is now a much more revealing amplifier (with the ATH-W5000's). I just got it back today and it's burning in on a sound card and my brain. Not as clear and detailed as the Solo Green, more of a richer sound.
This is a little class A amp and runs hot as hell, and it'll be nice as a space heater this winter. Just a better sound all round with real bass hits, now. But, still burning in, and still a little rough around the edges.
John
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 12, 2007 5:24:40 GMT
Johnsan My Class A 15W/Ch dissipates around 100W. They do indeed run warm.
SandyK
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 12, 2007 5:55:41 GMT
Miguel To me, opamps are something to be used when there isn't enough room for a discrete version,or modifying sound cards,DACs etc. I have yet to be convinced that any opamp combination can come close to a decent discrete Class A preamp or amplifier, whether on headphones or speakers. My tune, could however change a little when I eventually get the W1000s. In that case I will further refine the discrete version. SandyK
|
|
Nigel
Been here a while!
Watching over Gotham City keeping us safe
Posts: 2,064
|
Post by Nigel on Nov 12, 2007 10:14:54 GMT
I'm loving the LM4562 in the Green Solo.
Please don't anyone say bad things about it not being compatible, you'll put me off.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 12, 2007 12:39:28 GMT
Nigel The LM4562 is probably working well in the green Solo because the guy who designed it knew what he was doing , and optimised the layout? Let's face it, he would realise that a lot of the members of the forum are into opamp swapping ! Alex
|
|
mrarroyo
Been here a while!
Our man in Miami!
Posts: 1,003
|
Post by mrarroyo on Nov 12, 2007 13:02:07 GMT
Sandy, most will say that a discrete design is if well done superior to an op-amp! Man, I can't believe I am agreeing w/ you. Of course neither will ever be as good as valves.
|
|
leo
Been here a while!
Team wtf is it?
Posts: 3,638
|
Post by leo on Nov 12, 2007 14:18:54 GMT
I'm loving the LM4562 in the Green Solo. Please don't anyone say bad things about it not being compatible, you'll put me off. Agree with Alex, the quality of the supply feeding the op-amp in the Solo is ideal for a LM4562, the LM6172 is also a good op-amp IMO if used in a suitable circuit. If you have a good source Nigel then I'm not surprised you like the LM4562
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 12, 2007 23:03:50 GMT
A little off topic, but the new AudioTrak stereo soundcard has 3 op amps positioned onto sockets, they are Fairchild NE5532 (if that means anything to anyone here), so replacing them with the National Semi Conductor op amps is built into their design. I ordered one and it's now backordered for a while. I've got one of their cards now, and it's real good soundwise and feature wise. Korean and not expensive, $75, for their new Prodigy HD2.
johnsan
|
|
|
Post by minivan on Nov 15, 2007 9:35:36 GMT
i received my free sample of the lm4562, to replace the 2xlt1058 at the output of my zhaolu d3 DAC. after i rolled in the 2x lm 4562, the volume become low on both left/right output, and its has music but lots of white noise, just like listening to an not very well received radio signal. why is that so? any1 got any advise on this? the 2x opamp i replaced is at the lower right of the picture, near the left/right output
|
|
|
Post by dc on Nov 15, 2007 10:34:45 GMT
blimey! if that's the case then that's another reason to avoid the D3.0
At least the D2.0 and D2.5 you could roll in many of the common dual opamps
DC Sorry, see Minivan's corrected post about I.C. type. He meant LT1028, not LT1058 SandyK
|
|
leo
Been here a while!
Team wtf is it?
Posts: 3,638
|
Post by leo on Nov 15, 2007 10:41:12 GMT
|
|