What's op-amp?
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Luvya

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I see this term comes up often but have no clue about it.
Also, if I want to learn more about amp, which site do you people recommend? Let's say if I want to order one from JMT, what are the option I can entertain?
 
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austonia

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I could also use some help with this. thanks in advance from us noobs
 
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puppyslugg

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Opamp is short for operational amplifier. Opamps are basically a amplifier on a chip.
Quote:

Let's say if I want to order one from JMT, what are the option I can entertain?


You mean an amp from JMT? Or opamps?
 
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Luvya

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Amp. Sorry for not making myself clear

Op-amp is something I can buy from electronic store, no?
Also, I am hearing great thing about Meta 42. But I am not interesting in portability..heck! When I am outside I am driving!
So...the amp will be primarily used at home. How will this affect the components in Meta 42?
 
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JMT

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If portability is not an issue for you, then the size of the enclosure can accomodate larger components. Both on board and off board. Some if the better on board components (Elna Cerafine electrolytic capacitors for example) do not fit inside the smaller enclosures.....

....unless you are erix.
 
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puppyslugg

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Luvya:

If you have no need for portability, then you can bypass the VGD, buffers, etc. And as JMT mentioned, you can use a bigger box. Meaning: more room for goodies! Because you won't be needing the vgd, etc., you can then fit a bipolar regulated linear power supply. Which I believe would enhance the performance of the META.

If I were building a all out meta.....:

-ad8620 opamp w/ccs
-el2009/8 buffer (if you can find them) -or-
-el2002x4 (min)
-Blackgate bypass caps

And of course, the reg. ps. There are options here, too. Minumally, a lt1085/33 based ps., with good caps. If your pockets are deep, Jung super regulator, Sulzer/Borbely ps., etc.
 
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An op-amp is a very flexible type of circuit. The simplest thing you can do with it is to amplifiy a signal, though they have many other uses.

The nice thing about op-amps when it comes to headphone amplifiers is that virtually all op-amps come in 8-pin DIP or SOIC packages and they all have the same basic pinout. This makes it easy to take an op-amp out of an existing circuit and put a better one in its place to improve the sound. This isn't foolproof, but it frequently works.

There are thousands of different op-amp types, and hundreds of those are suitable for headphone amps and other line-level circuits DIYers can easily modify. Preamps, DACs, CD players, computer sound cards...all of these frequently use op-amps.
 
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Luvya

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Is there a pic of op-amp that I can look at? And maybe other pics of components if possible

What's VGD? @_@
If I were to order one with the spec that pupyyslugg just mentioned, how much will it cost? I just want to know the price range I am looking at right now..so I can plan ahead.
 
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JMT

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Luvya

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Btw, what about Corda Headamp ? I am well aware that there is also Porda Corda, but I think maybe the non-portable version will sound better, no?
One last thing, how do I know what components are in used for Corda headamp? I just want to compare...
 
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Quote:

Originally posted by Luvya
Is there a pic of op-amp that I can look at? And maybe other pics of components if possible

What's VGD? @_@
If I were to order one with the spec that pupyyslugg just mentioned, how much will it cost? I just want to know the price range I am looking at right now..so I can plan ahead.



Op amps can cost from between $5 and $16 dollars and more EACH, so make sure that you do some searching around here and find out what type of sound you are looking for so you can get the right op amps to produce it. The 8610/20 series have a really nice tube quality sound to them, and come highly recommended. Burr Brown op amps are slightly more detailed, IMO, but don't sound nearly as good!!

As to the rest, as in all things, whatever you are willing to spend, someone makes a product in that price range. Once yo uset a budget to build an amp, look around at what all you can get for that budget and then ask questions when you need to decide whether to buy one product over another. Most people here are quite knowledgable and helpful, so just ask and we'll do our best to steer you in the right direction!!!
 
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Can anyone describe the characteristics b/w the OPA-627 and AD8620? I know that OPA-627 is an op-amp for headroom cosmic, but what's the rave about the AD8620..and which is better?

Thanks
 
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ServinginEcuador

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Quote:

Originally posted by purk
Can anyone describe the characteristics b/w the OPA-627 and AD8620? I know that OPA-627 is an op-amp for headroom cosmic, but what's the rave about the AD8620..and which is better?

Thanks



Purk,

The OPA627 is hard to drive as it needs a higher voltage to maintain stability when compared to other op amps. In my CDP it sounded horrible every single time a dynamic note hit as it would gget unstable and sound screechie and scratchy until I turned off the CDP for a few seconds and then turned it back on. It is also kinda cold sounding, too soild state in it's sound!! It's very good at pulling tons of details from the music that other chips might miss.

The Analog Devices are another animal. They have more of a tube sound that most prefer here. Requires less voltage to work well and maintain stability, and have a really nice midrange sound.

My .02 worth!!
 
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Luvya

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From the way you guys sound...it looks like 8620 just can't be beat. So....why there are amps sell for $3000? I mean if 8620 is already this good...how much better will the op-amp in $3000 amp get?
 
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