Bonamassa,again

[Suckseeder]

https://youtu.be/Am4BrHLpCbs?si=M2WyWsRfvBtzNgq0

[pottedplant]

In the video he says that the PAB removes the entire tone stack, is this true? I thought it only removes some of the controls on these amps? I suppose it depends on which ODS?

[fred.violleau]

PAB is a tonestack lift, so it bypass the EQ

Fred.

[pottedplant]

yeah it's a pretty common technique to increase gain but what i'm saying is the concept is a little more hamfisted on say a boogie (mk1) because it lifts the whole stack right? doesn't the dumble implementation retain one of the controls?

[ayan]

yeah it's a pretty common technique to increase gain but what i'm saying is the concept is a little more hamfisted on say a boogie (mk1) because it lifts the whole stack right? doesn't the dumble implementation retain one of the controls?

In amps with Classic or Skyliner Dumble tone stacks, the preamp boost (PAB) will not retain any of the tone controls. However, given the nature of the tone stack, with two paths to ground, and the nature of the boost, there is some pronounced frequency shaping (= less bottom end) when the PAB is on. In the case of the Bluesmaster tone stack, there is only one path to ground and the PAB basically works like the boost in an old Boogie. In some amps the bottom of the stack is fully lifted, while in others there is a resistor to ground to make the effect of the boost more subtle.
G.

[martin manning]

Absolutely true about the HP filter effect in Skyline PAB. There is just a bit of the treble and mid controls, and a smidge of the bass left. This is true even if PAB is accessed by a center-off R/J switch and the 22M resistors across the PAB relay are out of the circuit. The treble control is able to affect the HF shelf by varying the series resistance.

[award70]

At around 4:28 he says using the master volume only affects the cleans and not the OD channel and that this is a characteristic of the skyliner. He demonstrates this on the amp. Is this correct? I looked at the #102 schematic and it looks like everything goes through the master volume no matter which channel you use.

[Charlie Wilson]

He is a bit off on that comment. Usually the HRM has separate volumes. You find Skyline tone stack in non HRM and HRM amps.
CW

[martin manning]

In the dual master circuits the labeling of the volume controls is misleading, i.e. the control labeled "Master" is actually the clean volume, which is bypassed in OD.

[award70]

I see. The circuits with a 2nd eq on the OD channel (like bluesmaster or HRM) feed the whole signal to the OD section and use the volume control of that section as the master.