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Discrete vs opamps... - Page 2

post #16 of 176
Quote:
Originally Posted by fewtch
That's what sacd lover was claiming to be doing, except the two amps in question were nothing alike. I'd say compare two solid state designs (discreeet vs. opamp) where both are powered by the same voltage, have similar levels of complexity (this might be more difficult to determine given the "contents" of the opamp are a mystery) and have similar volume pots, etc. PPA vs. Gilmore Lite seems reasonable to me, provided the PPA in question is powered the same and has the same component quality as the Gilmore.


A high end PPA with all the upgrades that cost twice the price of my discrete gilmore v1 wasnt a fair comparison? You have a state of the art PPA vs a then state of the art Gilmore design that was implemented with less expensive parts. If either amp was at a disadvantage was my gilmore v1. If the gilmore can handle more voltage or whatever thats an intrinsic advantage to the design.
post #17 of 176
Quote:
Originally Posted by sxr71
As good as they may have gotten, these op-amp devices are not really even designed for audiophile quality audio at all, they are all multi-purpose devices with different specs that could be used for audio. I see them as a kludge solution in audiophile grade applications. Coming from loudspeaker home audio, I was surprised to see how many op-amp based products are revered here and really they should be only excused in < $100 products or those that are built to be tiny.
Well when you get down to it, unbalanced mode operation is also a "kludge solution" designed to save money when all headphones have two drivers that will work with separate cables for each driver, no? So anyone not using monoblocks in the speaker world (or an unbalanced Gilmore Lite in the headphone world ) is compromising, right?
post #18 of 176
Quote:
Originally Posted by rickcr42
reality check time :

Point #1-the first "Op-Amps" were TUBE devices using 12AX7 tubes

Point #2-You folks need to get your heads out of the "tubes are colored" thought pattern and realise tube gear can be every bit if not more accurate as any solid state design known to man and if it is colored either by intent (to satisfy the ignorant) or by mistake because the designer has no clue.

Point #3-Every time i read "the opamp has a tube like quality" I crack up becuase it is more than obvious most have no idea what that means yet buy the device anyway because of the "con job" going on.

"sounds like tubes" has become a code word for "sounds great" yet the same person who would buy this "great sounding" piece of solid state gear (because most sounds like crap and will give you ear bleed) would in the next breath call tube gear colored as a way to slam it.

Right on rickcr42. No BS .... just the facts.
post #19 of 176
Quote:
Originally Posted by fewtch
That's what sacd lover was claiming to be doing, except the two amps in question were nothing alike except price-wise. I'd say compare two solid state designs (discreet vs. opamp) where both are powered by the same voltage, have similar levels of complexity (this might be more difficult to determine given the "contents" of the opamp are a mystery) and have similar volume pots, etc. PPA vs. Gilmore Lite seems reasonable to me, provided the PPA in question is powered the same and has the same component quality as the Gilmore.

BTW, I have no dogmatic opinion on this subject. Discreet has fewer parts, but opamps have no long circuit board traces and all the parts are much closer together with fewer solder joints, so the signal path will be a lot shorter and most likely cleaner.
If we were to rank design considerations and the impact they have on sound quality I'd say that good circuit design trumps having small signal path by a fair margin. It's like changing your source has a larger impact than upgrading your cables.

Ultimately, op-amps are multi-purpose devices that we happen to use in audio and much of the design of an op-amp based headphone amp seems to be to get the op-amp to "work" in the amp. That really can't be optimal for sound, but it makes for a cheap and easy solution. I think the reason that op-amp based headphone amps have gotten better is not so much that the op-amps have gotten better as we have gotten better in implementing them.


Regarding SACD lover, we don't know what sort of amp he compared to the Gilmore Lite, but pretty much every headphone amp that is greater than $299 is an 18v design at least. As for complexity, that doesn't matter as it is the op-amp based amp that is the more expensive one so the designer has more resources to work with.
post #20 of 176
IMO this thread is on unsteady ground given that the solid state amp people keep referring to is obvious even to me (I don't own one and haven't participated in any related threads). Of course, we have a moderator graciously watching over us...

Quote:
Originally Posted by sxr71
Regarding SACD lover, we don't know what sort of amp he compared to the Gilmore Lite,
Oh come on man... well, I won't say anything except maybe I'm psychic or something.
post #21 of 176
Quote:
Originally Posted by fewtch
Well when you get down to it, unbalanced mode operation is also a "kludge solution" designed to save money when all headphones have two drivers that will work with separate cables for each driver, no? So anyone not using monoblocks in the speaker world (or an unbalanced Gilmore Lite in the headphone world ) is compromising, right?
What does balanced operation have to do with op amps vs discrete designs?
post #22 of 176
Quote:
Originally Posted by fewtch
Well when you get down to it, unbalanced mode operation is also a "kludge solution" designed to save money when all headphones have two drivers that will work with separate cables for each driver, no? So anyone not using monoblocks in the speaker world (or an unbalanced Gilmore Lite in the headphone world ) is compromising, right?
Some compromises are acceptable given the cost to eliminate them. A balanced system will nearly DOUBLE my cost.

An op-amp in a $1000 headphone amp is ridiculous. Do you know what you could get in the speaker world for $1000 amp-wise in terms of design and construction? Even a $300 NAD amp does not use op-amps.
post #23 of 176
Quote:
Originally Posted by sacd lover
What does balanced operation have to do with op amps vs discrete designs?
Nothing. It has everything to do with solutions designed to save money (vs. better solutions) though.
post #24 of 176
Quote:
Of course, we have a moderator graciously watching over us...
well we are all in trouble now then 'cause i am about to be bad
post #25 of 176
Quote:
Originally Posted by fewtch
IMO this thread is on unsteady ground given that the solid state amp people keep referring to is obvious even to me (I don't own one and haven't participated in any related threads). Of course, we have a moderator graciously watching over us...


Oh come on man... well, I won't say anything except maybe I'm psychic or something.
I was composing my post while he posted that it was a maxed-out PPA.
post #26 of 176
Quote:
Originally Posted by fewtch
Nothing. It has everything to do with solutions designed to save money (vs. better solutions) though.
So when you have a discrete design thats better sounding and costs less money isnt that a better solution? Obviously you cant implement a discrete design for portables due to limited battery life. But for home applications? What I think is nothing but hype are the claims these op amp portables equal the sound quality of good home amps. I am sorry but I have done the comparisons .... I am doing one now ..... and I dont hear it.
post #27 of 176
Quote:
Originally Posted by sxr71
An op-amp in a $1000 headphone amp is ridiculous.
I agree with you. In fact I'll go out on a limb and state that $1000 is a bit too much to pay for any solid state headphone amp, unless it's a specialized piece of kit for balanced operation, or driving electrostats or whatever. Headphones are much easier to drive than speakers... better to put some of that money toward a good source IMO.

P.S. isn't the LaRocco PR-II somewhere close to $1000, and doesn't it use opamps?

Quote:
Originally Posted by sacd lover
What I think is nothing but hype are the claims these op amp portables equal the sound quality of good home amps.
Agree with that one as well, except I wonder why you aren't coming out and saying which amp you're talking about... or is this a sort of sideways attempt to criticize the amp in question, without incurring the wrath of its owners? I figured out long ago which amp you're talking about, but I won't say anything...
post #28 of 176
Quote:
Originally Posted by rickcr42
well we are all in trouble now then 'cause i am about to be bad
Rick, they have no experience and they keep trying to say our tubes are colored. Enough is enough ..... do we have to get rough with these guys.
post #29 of 176
It needs to be pointed out that not everyone believes the Gilmore Lite / Dynalo is superior to all opamp-based amplifiers and thus your personal taste is not particularly relevant for purposes of making absolute blanket statements.
post #30 of 176
Quote:
Nothing. It has everything to do with solutions designed to save money (vs. better solutions) though
not true.It is just a way and for some the best way,others not.I personally have and have built every manner of topology there is and at this point in life prefer the simple single ended class-a stage above all others on the sonic merits.It is a taste thing and no more

Back to Opamps and if discrete is better than chip amps or visa-versa

Chip amps are and must be a comprimised solution because they are a generic part and not a highly specialised part.The manufacturer can "suggest" uses but in the end they have no idea what you will be using it for so must design for just about any contigent over a very wide range of possibilities.
This is not inherently a bad thing but the limitations are WE have no access to the inner workings and must accept whatever parameters the substrate designer decided were best.
Sometimes this leads to a good sounding chip but even thenm is and must be a comprimise.

Next.There is no such thing as a class-A monolithic opamp and there can not be.the size of the package and heat dispersion alone would dictate a much bigger area (footprint) AND some means of heat sinking so right there is a huge built in comprimise since it is well known class-A sounds better and that is not just "hype" but reality
Not only are chip opamps not capable of class-A but some not even Class-A/B but are in fact Class-B amps though in the long run class-B may be a better choice than an imperfect A/B stage and here is why

Class-A : Output section transistors are always turned on full throttle so they do not have to respond to music signal but just pass them along amped to a new level.Unless this amp is fully balanced from input to output all the output section transistors will be the same polarity (All NPN or all PNP)

Class A/B : Output section transistors only respond to a signal of the same polarity as the input voltage so a positive going signal activates the "P" channel transistor and the negative going half of the signal activates the "N" channel part.This may sound OK in theory but the reality is there will be a "disconnect" at some point between the P and the N trasistors that is totally dependant on where in the range they are biased into class A and where A/B takes over.Because of the package size of the opamp the "A" zone is virtually non-existant.The chip could not cast off the heat so is not asked to and that means crossover distortion where the + signal goes to a - signal and the transistion zone between the N and P channel transistors are not in sync
The reason why most opamps use this method is because it is more efficient,uses less power and does not require additional heat sinking but NOT because it is a superior way.Cost savings,low heat generation no more.Not merit but cost

class-B : This is where the output transistor is either totally ON or totally OFF just like in class A/B.Where it differs is there is no "cross" to a polar opposite but like class A all the signal is handled by a single device (either N or P).It is like Class-a in that way but unlike Class-a which is always on full boogie ready to rock class-B is off until activated by an actual signal.This may sound bad but in reality to me is a better way than AB though not as good as A.
Any real limitation will be at the leading edge of an audio signal where it must go from "off" to "play" so if it lags a bit then the front end of a note will be slightly truncated but the GOOD NEWS is if designed properly all the notes will STOP at the same time since it will go to "off" as soon as there is no signal.
This means the lowest heat generation of all three types (most efficient) and no crossover distortion because the plus does not hand off to the negative

That is what a monolithic opamp IS.

Discrete Op-amps ARE superior because the user determines the mode of operation at each stage and can optimise each for both the position in the circuit and for end use.If that end use is music then fully class-a operation with no limits is not only a possibility but what every audio specific discrete opamp design I know of operates at !


So there is the "why" of my statement that a properly designed discrete opamp will whip the sh*t out of any monolithic opamp.they can and they do and the only reason to consider a chip amp is portable operation,heat generation or low cost but NOT because it has better sound and that is what all this is about right ?



Told ya I was gonna be bad but when I am bad I am good !
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