Hairball 1176 build pix thread

H to the Y! This is what we call "back with a vengeance" lol

Yea sorry agreed! Please move it admins!

I was told scary close.... we will see!

Pretty close.  In terms of electrical design, it's identical.  In terms of sound, it's pretty close based on hearing a real A rev blue stripe exactly one time in my life.

Other than that, it's just as noisy as the real thing.

I'd probably get another Rev D before getting another Rev A.  

Had a Revision D it was the holy grail compressor for me.

Well, as many of you know, I have one of the (now unavailable) exact clones Bluestripe clones from Pro Replicas of Poland. And I have compared it to an original and have experience with originals. It is absolutely identical in all but two ways:
1. It's a more solid chassis build
2. It doesn't have as much noise for some reason

But it sounds absolutely identical.

And as far as Holy Grails are concerned, a Bluestripe is THE holy grail for vocal tracking. There's nothing else like it in an 1176 / FET / ultra quick response limiter. Rev Ds are also great but slightly different strengths/applications.

A Rev A. does have a great grainy character, however the noise is nothing to ignore.  A Rev D. is mostly the same except for a different input circuit.  Less grainy character, but also about 15dB less hiss too!

I'm not sure why people think that one clone is more exact than another.. it's all about the parts used.  If you use the exact parts, then it's exactly the same.  Hairball uses the same parts as the Proreplicas does, as anybody does (except maybe Warm).

Besides, back when the Rev A. was made, parts had 20-50% tolerances, so no two boxes would sound identical..

HFE is an attribute of BJTs, not FETs.  HFE is the small signal forward current gain of a BJT.

Anyway, noise depends on the circuit and all it's various attributes.  Feedback, gain, gain staging, all that stuff.  The hairball kits came with sorted and matched JFETs though.

JFETs can also have lower noise than BJTs in some instances since they have much lower flicker noise and bias currents.  

I got out of 500 series so the Splices are sold. They are great, as I've posted previously. The only clones I've used that could hang with the UREI's.

The equivalent to Beta/HFE for JFETs is called Shockley's equation.  It's the relationship between Vgs (gate-source turn on voltage) and Id (output current).  It's non linear, unlike the BJT.

However, since we aren't comparing input current to output currents, there isn't a direct relationship to be had, and thus no direct HFE equivalent.

Matching JFETs is usually done by biasing the part and then swinging the gate voltage back and forth until you find the cutoff points.  These points can vary wildly, sometimes up to 20% different.  This is JFET curve tracing.  

Cool thx! That's what I was basically planning. 

I recall dandeurloo mentioning one basic part replacement in the Hairball 1176 that smooths out the overly-bright factor.