#124 started

[martin manning]

I would say so since you have it in hardware. Others with direct experience could comment. This is in clean mode? Of course you could go to OD, and increase the OD entrance trimmer setting if you want more drive.

[norburybrook]

No the OD is LOUD there's more than enough gain on tap there.

I was just surprised at the clean channel being so low in gain.

maybe I'll convert to the skyliner EQ, I suppose then it will be very similar to the #102 really so perhaps it's best to keep as is.

decision decisions

I've a feeling I might have tried changing my 102 to the classic stack and didn't like it at the time...... in fact yes I did.


so decision made I'm going to order some pots and change her to the #124 skyliner

M

[aflynt]

I didn't really like the Classic TS as much as Skyliner myself. With the Classic, I definitely preferred having the Deep switch engaged, otherwise it sounded sort of bland. Deep seemed louder because of the low end bump I think. I usually ran it with the bass and mid at 9-10 o'clock on Deep, but I had old Fender pots in there.

Haven't tried a 50 watt build, but my 100 watt was very loud in clean even in Jazz mode with the Classic TS. The preamp never really broke up much on clean with Single Coils, though. You probably should let it burn in for a few days before you judge, though. Things change a lot with new components at first.

-Aaron

[norburybrook]

yes I was thinking that 50w /100w would make a difference with a lower gain amp.

I'm puzzled though that with the jazz switch in, as I said, I doubt I'd be able to keep up with a drummer without the deep switch in it's really quiet.

I get no OD gain at all when in jazz mode , is that normal? I've seen a you tube clip of the Norwegian guy with his dumble and that OD nicely even in Jazz mode. My amp wont OD in jazz mode at all really.

I might check my components and wiring of the jazz/rock I've always omitted it on previous builds.

M

[aflynt]

I get no OD gain at all when in jazz mode , is that normal? I've seen a you tube clip of the Norwegian guy with his dumble and that OD nicely even in Jazz mode. My amp wont OD in jazz mode at all really.

I might check my components and wiring of the jazz/rock I've always omitted it on previous builds.

M

You definitely should be able to get OD in Jazz mode when on the OD channel. You might have to turn up the first volume and bring the tone controls up more but there should be quite a bit of gain available. Maybe you have a really low gain tube in V1?

-Aaron

[norburybrook]

I can if I have the deep switch on, but with it off it's really anaemic.

one thing; on the earlier layout I see the jazz/rock is a DPDT center off switch I've just used a DPDT regular on-on that shouldn't make a difference should it?

I was under the impression the center on was the manual switch for the PAB hence it doesn't work on the rear switch.


everything is sounding within the normal parameters of what I think hey should be except for the jazz/rock/ deep combinations.

as I said, with the deep off there's a HUGE jump between jazz and rock. with it on there's just a subtle change.


M

[aflynt]

one thing; on the earlier layout I see the jazz/rock is a DPDT center off switch I've just used a DPDT regular on-on that shouldn't make a difference should it?

...

M

Shouldn't make a difference. I had an ON/ON Jazz/Rock switch in mine. FWIW, this is how I had mine wired:

Layout:
https://tubeamparchive.com/download/file.php?id=39397

Schematic:
https://tubeamparchive.com/download/file.php?id=39396

I used a "Full" tonestack lift for the PAB on that. I believe #94 had that as well. I liked it better wired that way, but it should only really affect the PAB sound.

-Aaron

[norburybrook]

I've just wired in the updated mid switch instead of the deep and swapped out a 0.02uF cap for a 0.003uf on the Jazz rock switch. I saw that later amps user 0.0047uf rather than the 0.01 x2 (0.02uF) of earlier amps. Does that affect a frequency or is it a level?

Interestingly similar to the deep switch before it only seems to work on the jazz setting not on the rock. however I think there's a bit more gain now at the expense of some low end loss

It's the same as my #102 which doesn't have the jazz rock, it doesn't seem to do anything.


330pf capacitor and 4m7 resistor.



M

[norburybrook]

thanks aaron,

Is that a full tonestack lift then without the 22M?

might give that a go as it's not a million miles away from what it was.

I put in a separate mid switch so I have the old deep switch still wired up ready still.


what do the 270k resistors do tone wise?


M

[aflynt]

thanks aaron,

Is that a full tonestack lift then without the 22M?

might give that a go as it's not a million miles away from what it was.

I put in a separate mid switch so I have the old deep switch still wired up ready still.


what do the 270k resistors do tone wise?


M

Yes. Full stack lift removes the 22M resistors. I liked the way the PAB sounded better for the LPC set up that way. Not sure exactly what the 270k resistors do in the Deep circuit. Maybe isolate the bass pot from the volume for the filter?

-Aaron

[aflynt]

I've just wired in the updated mid switch instead of the deep and swapped out a 0.02uF cap for a 0.003uf on the Jazz rock switch. I saw that later amps user 0.0047uf rather than the 0.01 x2 (0.02uF) of earlier amps. Does that affect a frequency or is it a level?
M

I thought the .01x2 on the Jazz Rock on 124 was connected in series (.005uF)?

-Aaron

[norburybrook]

actually my bad, they are I should get a 0.005 uf cap and put it in there really.



Marcus

[martin manning]

Seems like the Skyline tone stack with PAB is an evolution from the Classic with Deep (which was a Fender thing), and since we have seen more than one that has been converted, it appears that the Skyline is perceived as an improvement. Also, I don't know that anyone really knows exactly what #124 looked like before the upgrade.

[jelle]

Seems like the Skyline tone stack with PAB is an evolution from the Classic with Deep (which was a Fender thing), and since we have seen more than one that has been converted, it appears that the Skyline is perceived as an improvement. Also, I don't know that anyone really knows exactly what #124 looked like before the upgrade.

Well, it did have a DEEP switch. And a 330pF (?) ceramic treble cap.

Now this build has a .0022uF mylar treble cap and a DEEP switch. But the MID BOOST is always on.

[norburybrook]

I've ordered some more pots and caps so I'm going to convert to the #124 low plate skyliner as was originally photo'd and reverse engineered.

I was playing it yesterday evening and as it is with the odd serendipity mistake, it's a nice sounding amp. Very different form my #102 but I wouldn't say better or worse.

I would say, maybe because of the lower filtering and the lossy tone stack on this amp, it's a bit more ragged as you have to turn it up louder all round.

it's not a big job to change to the skyliner so I'll do it and then evaluate.


thanks for everyone's input into this as always, couldn't have done it without you. I've learned a lot more than just reading a book doing this so I'm pleased.

At the end of the day 'good' sound /tone is in the ear of the beholder so as long as an amp is functioning safely it doesn't actually matter what's going on if you like the sound of it.

as an amateur though I feel I need to build exactly as per the layout /schematic first and only then can I start to experiment. Bit like cooking I would say

time to get some plywood I think and embark on my first cabinet building and covering!!

watch this space.


M