[nesty]

I dont know if it is only me but I have Sparkos SS3602, OPA2209 and OPA1692... and I have AD4084 but have not yet engage it in.

OPA1692, clarity and details which translates to better highs., bass it can go deep but not basshead, width and depth is there, mids are a bit laid back but just right.
OPA2209, better instrument separation than 1692 as I compare this with SS3602, bass same with 1692, I can say it's identical when it comes to width, depth and soundstage with 1692. The mids are forward but just on point. highs are there not sibilant but 1692 has better clarity.

 

[davveswe]

I have problems with my burson V5i. DC offset is 0.2-0.4V. What causes the high offset?
My amp uses OPA2134 as standard.
Tested other opamps and they are okey

 

[raoultrifan]

This DC is pefectly normal for this op-amp, just check it’s datasheet (voltage off-set, then multiply with the gain used).

In what device are you using it and in what stage?

 

[spacequeen7]

made slightly better access ,to bad Sparkos won't cooperate

 

[DSebastiao]

I don't know if this is the appropriate thread, but i stunbled across the CMoy, i like the project and i'm thinking of doing it, i've made some little electrical projects in the past so i'm ok with the schematics, i'll give a better look at the website, but want to ask if there's any other article that i should read? What type of tweaks can be done or what tweaks does the community unanimously recommend?

Also, this is suppose to cost around 20$ right? But how does it compare to other amp's? In what price region would you put it?

Anyone from europe? Where's the best place to get all the components?

 

[Rroff]

I used Tangentsoft's guides when I first built a CMoy type amp - it is an excellent resource for those with basic electronics experience wanting to get a handle on the audio side of it.

The tweaks are almost endless from different types and configurations of capacitors, expanding on the basic gain stage with various current buffers and so on. I completely changed the power supply section using a DC-DC convertor to generate a negative rail instead of a virtual ground and then added regulators to clean it all up. You can also implement things like low pass filters on the signal input to give the amp better resilience against EMI/RF, etc. as well.

To be frank while you can build it for "$20" I wouldn't approach it as a way to save money on an amp and to get the best results you are going to be looking at more like double that. With a few simple tweaks you can get very good results from a CMoy type circuit if the layout is reasonably good.

I use Farnell and Mouser a fair bit but also have a fairly well equipped local indy which can be useful.

 

[spacequeen7]

Received Burson dual V5i today ...next level in comparison to :
Second best synergy -OPA2111KP
OPA2134PA
OPA2107
MUSES8820
OPA1612AID
LME49860NA
OPA2604

Sparcos SS3602 (incompatibility-two tested )

 

[SpudHarris]

49880 anyone??

 

[imran27]

49880 anyone??

Damn, I was just wondering about it a week ago. I saw these on Element14. Technically they measure worse.

Anyways, my next investment would be in OPA1652 and probably ADA4610-1/-2 (this I am really hopeful for)

 

[pelopidas]

My SSOP boards finally came yesterday and I soldered up some 1692. I used an aligator clip to hold the chip in place and that made soldering pretty simple. I got a q-tip and put a drop of water on the chip to keep it from overheating and used plenty of flux. I was a bit worried but none of them died.
Sonically the 1692 is very similar to the 2209. Very resolving and detailed with good imaging. However, it also sounds like it has a certain sheen or gloss on it. Not at all unpleasant. It reminds me of bypassing my power caps with teflon. The problem I do have is that it has a relatively high offset. I have not been able to tame that in my headphone amp. The best I could do is around 50mv which makes me really uneasy when plugging in expensive headphones. Some of the chips were in the 100+ mv offset. They are not damaged and sound great in my DAC where that does not matter. Anyone wanting to use these in a CMOY though should be very careful to measure the offset before just running with them. The same goes for the Burson V5i. Those have crazy offset.
On a different note, I decided to relisten to some old favorites to see how they compare to the 2209 and the 1692. LME49990 used to be a safe go to. Now it sounds dull and undynamic and with a white glow, much like a silver mica capacitor produces. The 797BRZ is a muddy mess. I was actually very surprised at how poorly it competes with the 2209. the 797 is still populating my HTPC Xonar, however, I just ordered a bunch of 2209 and 1692 to replace those. The LME49860 did put up a good showing. It does not have the incredible clarity and detail of the 2209 but it also was not muddy, confused or plagued with some other disqualifying characteristic.

So Spud, what about the 49880? Don't keep us in suspense

 

[FritzS]

Which real buffer ICs (gain 1) are now available?

I know about:
BUF634, LH0002 (old, the first on market?), LMH6321, LME49600, LME49610, LT1010, ......

PS: Under real buffer I mean ICs similar to the „Diamond Buffer“ design from Walt Jung
http://waltjung.org/PDFs/Op_Amp_Audio_Buffers_1_ED_090198.pdf
http://www.waltjung.org/PDFs/WTnT_Op_Amp_Audio_2.pdf

 

[raoultrifan]

Both BUF634 and LME49600/LM49610 can be used with success. They're extremely low-noise and low-distortion and have a high output power.

Some useful examples would be:
- BUF634 used by Dr. Meier Cords in his amplifiers
- LME49600 used in Benchmark DAC3

I've personally did the TI recommended design with LME49720 and LME49600 and amplifier was measuring very well, also the sound was neutral and powerful enough to drive all of my cans. Also, swapping LME49600 with BUF634 changed nothing in my measurements and hearing, so...maybe internally there's not much of a difference between the too...don't know.

 

[LaughMoreDaily]

Thanks for your suggestions and sharing your most recent experiences.

I noticed that these ic chips are tiny. My understanding is that I would have to solder them onto some kind adapter so they would work in a dip 8 package?

Also, when ordering, how would I tell which one to order of a particular model. There are a combination of letters following the chip model (e.g. OPA1692AID vs OPA1692AIDR)...more specifically for the Zishan Z2, which I believe is a dual version dip8 configuration...

Also, the nice surprise with these suggestions is that I just put 3 opamps into my Mouser cart and with shipping it was under $30! Much more doable compared to the Burson and Muse options, and I can experiment...

Again much appreciated to ask the responses!

Thanks for letting me know these are on Mouser. I couldn't find them.

 

[toear]

Thanks for letting me know these are on Mouser. I couldn't find them.

 

[FritzS]

Both BUF634 and LME49600/LM49610 can be used with success. They're extremely low-noise and low-distortion and have a high output power.

Some useful examples would be:
- BUF634 used by Dr. Meier Cords in his amplifiers
- LME49600 used in Benchmark DAC3

Jan Meier use two BUF634 parallel
http://meier-audio.homepage.t-online.de/classic.htm

Thomas Funk use probably LME49600/LME49610 but he don't give hints about.
http://funk-tonstudiotechnik.de/LPA-2S-englisch-300.pdf

I've personally did the TI recommended design with LME49720 and LME49600 and amplifier was measuring very well, also the sound was neutral and powerful enough to drive all of my cans. Also, swapping LME49600 with BUF634 changed nothing in my measurements and hearing, so...maybe internally there's not much of a difference between the too...don't know.

BUF634 offers in BW mode more quiescent current (about 15 ... 20mA) and running at low volume level in class A.
LME49600/LME49610 offers nearly the same.