Choosing replacement darlingtons for Scrambler

[mark2]

The Ampeg Scrambler used 2N5306 which aren't practical for me to get.  A lot of people report having good luck with BC517, and some reports of MPSA14.

Are there any specs to be concerned with when picking a replacement other than hfe? I ask because I'm trying to choose some SMD transistors that'll work well with this circuit, and not sure what else to look at.

I was considering the MMBTA14LT1G since it seems to the equivalent of the MPSA14.  But wondering if the MMBT6427LT1G might behave more like the BC517 that everyone loves.

Any tips other than to just try them and see how they sound? Thanks!

[iainpunk]

for this specific fuzz, the transistors aren't too critical, most darlingtons work, even just cobbled together ones made from 2 normals. you can also look in to sziklai pairs if you are going to cobble them. (negligible difference in sound, a tad more linear at high gains)

also, D4 and D5 aren't actually put on the board in 95% of original units

cheers, Iain

[mozz]

 I have some old 70's darlington pulls here in the TO-98 package, i can measure gains if you want some.

[mark2]

for this specific fuzz, the transistors aren't too critical, most darlingtons work,

Thanks, I won't worry too much about it. I'm going to try the MMBTA14 to start with.