Input impedance of the Orange Squeazer and Tube Screamer?

[lowvolt]

Hey folks.  Just out of nagging curiousity, I've been trying to locate the input impedance of your buck standard Tube Screamer and clones, as well as the average Orange Squeazer and clones.  Any help on this?

Thank you!

[CurtisWCole]

Roughly 510k for the tube screamer.

[Kesh]

about 250k for the orange squeezer, but then it drops when the jfet opens up

[fuzzlab808]

The tube Screamer has a lower input impedance: It's 510 K in paralel with the impedance of the transistor that is: hfe*5K. So it depends of the hfe of this transistor. If a typical hfe of 250 is the case, then 5K*250= 1250K.   510K in paralel with 1250K is 370K.  So, it's not a super high input impedance.

[Kesh]

if we're being exact i'd just add that modern TS clones (seeing as you asked about them) will probably have something like a 2n5089 in (mine does), taking tranny Zin up to maybe 3Meg, so total Zin at about 430k

[lowvolt]

Thanks ... 430k +/- is fairly liveable.  I've been using both with my bass (passive J) and it seems to sound ~ok~ with the OS, but sounds better if I use a mic pre as an unput stage first (840k impedance).  So I was wondering whereabouts these two things measured.  My active bass (obviously) isn't as picky.  I typically have been running the TS in parallel with a dry signal, using the mic pre as a splitter and a little 2 channel mixer as a post FX remixer.

I guess I should not have sold the two Avalon U5s I had ...... that'll teach me!    

I've been using a little ART Tube Pre as an input stage for my bass with stellar results.  Cork sniffin producer types that try using them on vocals literally HATE those little ARTs.  But for something as unrefined as a ~rock bass~ they seem to work fine.    

Thanks for the help fellers.  

[Kesh]

standard orange squeezer has an input cap that isn't too bass friendly. i would up it.

[lowvolt]

standard orange squeezer has an input cap that isn't too bass friendly. i would up it.

To what value?

[lowvolt]

standard orange squeezer has an input cap that isn't too bass friendly. i would up it.

Are you speaking of the 4.7uf cap that connects to ground and the volume control? Or the one that isn't connected to ground on the other side of the volume pot?

[Kesh]

the cap at the input. it's 47n usually. i would try 100n or 220n

[lowvolt]

the cap at the input. it's 47n usually. i would try 100n or 220n

Oh geez!      

Sorry .. my eyes SAW "input" but my brain said "ouput".      I'm totally fried .. I only got two hours of sleep last night and my brain is mayonaise.    

DOH!   

Thanks for straightening me out on that! 

[lowvolt]

the cap at the input. it's 47n usually. i would try 100n or 220n

So change the 473 to a 104 or 224 then.  Got it.  Thanks! 

[lowvolt]

Thanks everyone, for the help and suggestions.  Some information offered in little bits can go a long way.  I appreciate the help.