Feral Feline
Well-known member
Socket it or breadboard it for sure!
KAT Treble Booster Strip Board layout
- Thread starter ac30irons
- Start date
Feral Feline
Well-known member
DAGNABBIT!
I missed a 22k on the Cornish schematic posted by mkstewartesq:
I was checking a new layout against the schematic when I noticed my error — so I stuck the two schematics side-by-side to see what's what other than the obvious C5 & R7 on the Plush.
Here's the new layout(s) minus that stinkin' 22k I missed:
I was pretty happy with the layout, got it down to 9x9 with a bit of cheating, and then 9x11 with less cheating — then I spotted the missing 22k.
It'll take a lot more kajiggering to get that 22k to nestle into the layout while still switchable between Cornish and Plush versions.
I think I'll take a wee break from it, though.
Feral Feline
Well-known member
Nudder ting...
Cornish BC149 is available in TO-18 or SOT25, so might need another column of space if using BC149 or if trying to switch up the transistor as well.
Not bad, remains only 1 jumper and 2 cuts.
Still have yet to add a GAIN or VOLUME pot...
... AND that damn 22k.
Cornish BC149 is available in TO-18 or SOT25, so might need another column of space if using BC149 or if trying to switch up the transistor as well.
Not bad, remains only 1 jumper and 2 cuts.
Still have yet to add a GAIN or VOLUME pot...
... AND that damn 22k.
Ffs shits getting too heavy for me now - might knock up an npn Rangemaster
To confuse things further, here is another schematic for the bc149 - which, well ….. the plush. No extra 22k and includes C5 and R7. Go figure.
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Feral Feline
Well-known member
Paul is pretty meticulous...
Nonetheless, we are assuming that all the schematics posted are correct and free of mistakes of their own.
Nonetheless, we are assuming that all the schematics posted are correct and free of mistakes of their own.
mkstewartesq
Well-known member
And the Cornish BC149 booster schematic I posted upthread also came from Paul. Since the term "orange label" just refers to the fact that one of the boosters on Brian's board at one time had the word "IN" written in Sharpie on an orange label to make sure the input cable wasn't inserted into the wrong jack, that tells me that the Cornish booster design using a BC149 evolved over time. Which makes sense, as Brian was using them for approximately 15 years. Sometimes he even used two in line (or two specially built by Cornish in the same enclosure) to cope with long cable runs on big stages.
M
Edit to add – here’s a picture of my replica orange label booster just to illustrate. There were plenty of times the boosters on his board did not have this label. For the record, his boosters never had a foot switch or an LED - that was a custom modification for me to avoid having to constantly unplug the jacks when done playing to avoid killing the battery
Nice info Mike - I’m building it up tomorrow and will audition a few different transistors.
Feral Feline
Well-known member
Excellent info, mkstewartesq, many thanks for clarifying what the "orange label" was about, I thought it might be an Orange Amps derivative.
I'm not as versed as you and ac30irons in all things May-Queen.
For sure I'm going to ignore that extra 22k, for now.
If anyone breadboards and compares the circuit with and without the extra 22k, and finds it makes a substantial difference, then I'll revisit my layout and see about swapping in the extra 22k via an extra pole tacked onto the Cornish-Plush switch, ie make it a 4PDT.
I'm not as versed as you and ac30irons in all things May-Queen.
For sure I'm going to ignore that extra 22k, for now.
If anyone breadboards and compares the circuit with and without the extra 22k, and finds it makes a substantial difference, then I'll revisit my layout and see about swapping in the extra 22k via an extra pole tacked onto the Cornish-Plush switch, ie make it a 4PDT.
mkstewartesq
Well-known member
I actually still have the plush TB set up on my breadboard as that is the last project I worked on a few weeks ago. When time permits, and if @ac30irons hasn’t already done so and reported back, I’ll try adding the extra resistor and any other differences to the schematic to my build to see if it makes any difference. There is a BC 239 in there are currently per the plush schematic –I’ll have to use something different than a BC149 as I have none of those but I think I have some extra BC109s floating around.
M
I’m supposed to have a breadboard coming tomorrow (I don’t actually have one) but there is no sign of it being here. If it should turn up, I will have a go but it will be my first time breading anything. I defiantly have some bc109s and bc239s plus all sorts of others, accept bc149.
So it’s built and these are my findings.
That 22k makes not a jot of difference, or at least not one I can hear. As my breadboard didn’t turn up, I made a slight amendment to the layout and socketed it. I went between that and resistor leg clipping
The difference with adding in C5 and R7 is a very slight high cut. The only way I could hear it was by letting the guitar feedback and toggling between the two. I would say it’s negligible.
I auditioned a load of transistors and the humble 549c came out on top for me. For a low gain option 2222a. I will probably add a switch with two options.
Here is a little gut shot.
That 22k makes not a jot of difference, or at least not one I can hear. As my breadboard didn’t turn up, I made a slight amendment to the layout and socketed it. I went between that and resistor leg clipping
The difference with adding in C5 and R7 is a very slight high cut. The only way I could hear it was by letting the guitar feedback and toggling between the two. I would say it’s negligible.
I auditioned a load of transistors and the humble 549c came out on top for me. For a low gain option 2222a. I will probably add a switch with two options.
Here is a little gut shot.
mkstewartesq
Well-known member
So it’s built and these are my findings.
That 22k makes not a jot of difference, or at least not one I can hear. As my breadboard didn’t turn up, I made a slight amendment to the layout and socketed it. I went between that and resistor leg clipping
The difference with adding in C5 and R7 is a very slight high cut. The only way I could hear it was by letting the guitar feedback and toggling between the two. I would say it’s negligible.
I auditioned a load of transistors and the humble 549c came out on top for me. For a low gain option 2222a. I will probably add a switch with two options.
Very cool - and consistent with my own experience that the KAT Push is almost indistinguishable in sound from the Cornish BC149 (save for a tiny, almost negligible bit of extra brightness, as you noticed - im my case, it was so light I just chalked it up to component tolerances)). But that makes sense, as even the KAT website makes clear the Plush is meant to replicate the Cornish TB ("Sound-wise, this TB has been developed to emulate the 1980’s era of Brian May’s tone with approximately 33dB of gain, so think Queen from the late 70’s through to the end. Think Wembley… Think Live Aid!").
I've really enjoyed this thread.
Mike
I hear you Mike.
I’m just happy I have been able to positively contribute to a thread.
paulbarrette
Active member
interesting. I have to build one now. I have a germanium treble booster (ac128), but I have a bunch of germanium npns I want to test. I may try a few silicons as well.
thanks for posting the schematic and layout
Pb
thanks for posting the schematic and layout
Pb
Good luck dude, fyi - I would not bother with the switch to swap between the Cornish and Plush - the difference is so negligible.