Mark III questions

[Chase42147]

Hey guys, finally joined the forum after reading here for ages! I've been really interested in Mark III's lately, mostly because of John Sykes' sound on the self titled Whitesnake album and debut Blue Murder album. I have a few questions about them. First of all, what does KRG and KDRG mean? I see it all over the place but can't figure out what it means. Also, it seems like the Simul-Class is the popular type of Mark III, how can you tell if one is Simul-Class?

 

[sloanthebone]

Not sure of the “K” but here are the ones I do know:

H = 100/60w

D = Simul-Class

R = Reverb

G = Graphic EQ

X = Export Transformer

 

[Markelicious]

Hey guys, finally joined the forum after reading here for ages! I've been really interested in Mark III's lately, mostly because of John Sykes' sound on the self titled Whitesnake album and debut Blue Murder album. I have a few questions about them. First of all, what does KRG and KDRG mean? I see it all over the place but can't figure out what it means. Also, it seems like the Simul-Class is the popular type of Mark III, how can you tell if one is Simul-Class?

K is for Coliseum. 180 watts.
Simul-Class will have a switch on the back that you can choose Class A (15 watts) or Simul-Class (75 watts).

 

[Chase42147]

Oh, that makes sense. That simplifies it a lot. Which Mark III's have the power level selector on the front?

 

[Markelicious]

Oh, that makes sense. That simplifies it a lot. Which Mark III's have the power level selector on the front?

I think Blues and Greens had them in the front with the long chasis

 

[scotticus]

One thing I've always wondered...on a coliseum with simul class, the switch on the front is still labeled full power/half power. Is this a true half power switch, or is it a simul class/class a switch that they didn't re-label for the purpose of not having to fabricate new faceplates? Or maybe a better way to put it, is a KDxx amp always in simul class mode, with the ability to drop down to half power, and if so, which tubes are being shut off to achieve this?

 

[Chase42147]

I think Blues and Greens had them in the front with the long chasis

Oh ok, so the short heads just had them on the back? And one more question, were there any long heads that aren't Coliseum heads?

 

[Markelicious]

Oh ok, so the short heads just had them on the back? And one more question, were there any long heads that aren't Coliseum heads?

The Simul-Class switch and Reverb knob are on the back of short heads, on the front of Long heads

 

[GJgo]

Oh ok, so the short heads just had them on the back? And one more question, were there any long heads that aren't Coliseum heads?

Yes, many of them in all stripes.

 

[GJgo]

One thing I've always wondered...on a coliseum with simul class, the switch on the front is still labeled full power/half power. Is this a true half power switch, or is it a simul class/class a switch that they didn't re-label for the purpose of not having to fabricate new faceplates? Or maybe a better way to put it, is a KDxx amp always in simul class mode, with the ability to drop down to half power, and if so, which tubes are being shut off to achieve this?

On the IIC+ & III Coliseums, the half power switch is a 22K 2 watt dropping resistor that lowers the screen voltage about 100 volts, drops total wattage down to around 50.

There are both KRG (180W) & KDRG (120W). The KDRG is the odd Mark that the MIDDLE pair is the Simul pair and can take 6L6 or EL34. However, Simul Colis are not set up the same as Simul 4-tubers and there is some argument about if it's a true Simul circuit. Simul Colis are always in "Simul" mode. All 6 tubes are always active.

 

[Chase42147]

Thanks for all the replies guys!

 

[scotticus]

On the IIC+ & III Coliseums, the half power switch is a 22K 2 watt dropping resistor that lowers the screen voltage about 100 volts, drops total wattage down to around 50.

There are both KRG (180W) & KDRG (120W). The KDRG is the odd Mark that the MIDDLE pair is the Simul pair and can take 6L6 or EL34. However, Simul Colis are not set up the same as Simul 4-tubers and there is some argument about if it's a true Simul circuit. Simul Colis are always in "Simul" mode. All 6 tubes are always active.

Thanks for that!

 

[mesaboogie6L6]

I have a KDRG and it's 150 watts.