Jfet complimentary input stage or Jfet LTP?

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which one would you prefer is it complimentary input stage or Jfet LTP.

According to cordell book he speaks that matching the n and p channel in complimentary input stage is more time consuming and also you just need to buy alot of them to match it properly or it ends up with second harmonic distortion.

where as the LTP doesnt have that problem so which one is best sonically?
 
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Hi rhythmsandy,
Bob is 100% correct. These days especially, go for the standard differential pair. Trying to match complimentary pairs is extremely difficult with J-Fets, and you will never actually get a match.

Personal opinion ... J-Fet Differential pair (single) sounds the best if the rest of the design is up to it.

-Chris
 
Hi rhythmsandy,
Bob is 100% correct. These days especially, go for the standard differential pair. Trying to match complimentary pairs is extremely difficult with J-Fets, and you will never actually get a match.

Personal opinion ... J-Fet Differential pair (single) sounds the best if the rest of the design is up to it.

-Chris

Not complimentary but complementary! Completely different meaning.
 
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Hi dadod,
I therefore compliment you on your catch. Spell check + holiday (in Canada) + no coffee yet means my posts ought to be interesting today. I'm falling asleep here.

I have to sort that coffee situation out fast! Hurry up coffee maker!

-Chris :)
 
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Not complimentary but complementary! Completely different meaning.
The term "complement" once would have been learned at primary/grade school. I think the subject was Geometry, where any two angles were complementary if they summed to 90°. Obviously, that isn't the only application for the term.

Nowadays, spelling gaffs go ignored among countries in which English is the lingua franca. A problem arises though, when we meet in a global forum as here, and translation software gives inappropriate or nonsense results for mis-spellings.

It's also easy to offend when you don't realize how slang or street talk expressions will translate via a Google 'bot. :eek:
 
Hi rhythmsandy,
Bob is 100% correct. These days especially, go for the standard differential pair. Trying to match complimentary pairs is extremely difficult with J-Fets, and you will never actually get a match.

Personal opinion ... J-Fet Differential pair (single) sounds the best if the rest of the design is up to it.

-Chris

I see alot of matched pairs available for sale.

If matched then wouldnt that be better?
 
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It's down to what the sellers mean by "matched". Close, near as possible with the number on hand or just approximate? If you visit the Pass forum, you'll find most solid state designs there are based on FETs and the issue of buying or matching pairs is always on the agenda. Buzzforb seems to take a lot of interest in what's available and suitable there.

If FETS interest you, it may be worth a visit and a bit of reading.
 
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This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.