Matching Jfets for Dr Boogey -- How close?

[ghostsauce]

I built the 2nd one here (GIJM II) and tested all my fets the other day, found the best combo and plugged em' into my DB. I biased them at 6v where my ears liked them best.. it was more clear and amplike this way. Actually it's kinda mystical in how amplike it sounds now.. but anyway my question is how closely have you guys matched yours? And do you think I should try to find a closer match? These are the values I pulled:

.74   282
.74   277
.74   262
.74   272
.75   270 (Q5 buffer)

[kingswayguitar]

i'm new to the Boogey and didn't even know to match them 

my j201's varied from 0.6-1.0 vgs and it sounds ok

i remember when it was on the breadboard i added one stage at a time and tested the sound

after 2 stages it was pretty cool

after 3 it was melting my face

the 4th i just had to look at my strings and they rocked

lots of fun eh

[defaced]

I don't see why they would need to be matched at all. The circuit does not behave like a phaser for example where the fets work together to produce the eeffect. Here each fet is independant and works its stage irrespective of the other stages. You may get more interesting results if your intentionally mis-match the fets to take advantage of their different clipping thresholds/characteristics.

[lonewolf]

I think that's why each J201 has a trimmer..

[ghostsauce]

Well, the closer the match the better it sounds as far as my ear is concerned.. Can't remember where I originally saw this info, but once I used a matched set there was a major difference. Less harshness and more amplike gain.

[J0K3RX]

I don't see why they would need to be matched at all. The circuit does not behave like a phaser for example where the fets work together to produce the eeffect. Here each fet is independant and works its stage irrespective of the other stages. You may get more interesting results if your intentionally mis-match the fets to take advantage of their different clipping thresholds/characteristics.

Agree with you... A phaser needs jfets that are all not fully on or fully off at the same time.

On the DrBoogie Each stage is different so unless the jfets are wildly out of spec I can't see where matching them would do much good... I have heard talk of there being "fakes" or relabeled J201's and such but I have not encountered any yet, that I am aware of anyway. If they are off to a greatly noticeable degree then they will probably sound like sh!t matched or not matched since it may cause unwanted noise or whatever depending on which way they go. The fact that you have to bias them would make matching them pointless, no? They are all reacting differently.. Plus the fact that everybody is gonna bias them a little differently means no two will be exactly the same... I think if you are hearing a difference when using matched vs. not matched your ears may be playing tricks on you..?

[deadastronaut]

ive never had to match j201's..

ive always trimmed by ear..

dr boogie tip:  turn guitar down, set trims for max attack/decay....i e. no gating,  go from there..

[ghostsauce]

Hmm, weird. I don't know what to say then... Maybe it just made finding a bias I like easier since the trimmers are all pretty much set the same.

Before I'd always trimmed by ear and was happy with it, but I figured I'd push it further

[deadastronaut]

ive been working on a 1590b dr boogie layout, but i'm thinking to use sockets for the tones stack section components,  

the treble has always been too harsh imo, and the bass lacking,

i may just bread it and have a tweak instead though. and add a switch or 2 for stages or caps, not sure yet..i'll try it and see when i get time....

[ghostsauce]

*nod*
The 10nf cap across lugs 1&3 of the volume really make a difference for he harshness.. been wanting to try 15nf actually to see if it gets even better. And that other cap I posted in the other thread worked great for extra bass. One thing I noticed with the fets I'm using now (or their bias I guess) is that it is less harsh still and more clear. Not undistorted but articulate.