goldtop0 wrote: ↑Sun Jan 01, 2023 9:03 am
..... but is somewhat strident and piercing at volume
It's an EL34 amp. Isn't that what they do?
To a certain degree but not to the point of overpowering the senses
It's just a little too raspy on the bridge pup of my LP which is what I don't like, don't get that with my other Ms, 1974X and 1962.
Last edited by goldtop0 on Sun Jan 01, 2023 1:05 pm, edited 1 time in total.
goldtop0 wrote: ↑Sun Jan 01, 2023 11:28 am
With these 4 input Ms I tend to jump the channels and playing at high volume is not generally not the norm for me these days so relief at medium to lower volume playing is what I look for now.
The Bright cap on this one is 4.7nf apparently.
A 470pf/500pf might be what you are after if you blend the channels. It will still give you a bit of bite without the that super aggressiveness of the 4.7nf/4700pf.
After doing some research, the bright cap is soldered to the PCB that the pots are attached to so it would be a relatively simple mod. Famous last words; desolder the old cap and install the new one. I don't know how labour intensive removing the PCB from the chassis would be however.
The cathode arrangement on the bright channel, if what I read was true, is a 820R resistor bypassed by a 680nf cap. This also will thin things out a bit more than the 2.7k/680nf arrangement.
Thanks so much for your input Fuzz.
I'll talk with Clarry about this as like you he's got the nouse with all this techno stuff. He'll get the circuitry sorted and we'll take it from there.
goldtop0 wrote: ↑Sun Jan 01, 2023 1:02 pm
Thanks so much for your input Fuzz.
I'll talk with Clarry about this as like you he's got the nouse with all this techno stuff. He'll get the circuitry sorted and we'll take it from there.
No worries. Let us know how you get on and which way you decide to go.
goldtop0 wrote: ↑Sun Jan 01, 2023 9:03 am
..... but is somewhat strident and piercing at volume
It's an EL34 amp. Isn't that what they do?
To a certain degree but not to the point of overpowering the senses
It's just a little too raspy on the bridge pup of my LP which is what I don't like, don't get that with my other Ms, 1974X and 1962.
Got an EQ like a Boss GS-7 handy? Pull out the uglies and have a listen to what's left.
Beyond a critical point within a finite space, freedom diminishes as numbers increase. This is as true of humans as it is of gas molecules in a sealed flask. The human question is not how many can possibly survive within the system, but what kind of existence is possible for those who so survive.
Optical wrote: ↑Sun Jan 01, 2023 12:31 pmThe 820R value is thicker/more bass/less treble shelving than the 2k7 but yeah
I believe the 820R/680nf was featured in the early Marshalls with the split cathode arrangement before they went to the more common 2.7k/680nf arrangement. The 820R/680nf rolls off the lower frequencies from 285Hz downwards and 2.7k/680nf from around 86Hz.
No that's not quite right.. the resistor sets the unbypassed gain, lower values are more gain.
There's about 12 different superlead circuit variations, maybe more? The famous evh amp had 820R//680n on the first stage but I'm not sure if that was ever a factory config, but who knows with Marshalls ambivalence to part values
Optical wrote: ↑Sun Jan 01, 2023 6:56 pmNo that's not quite right.. the resistor sets the unbypassed gain, lower values are more gain.
There's about 12 different superlead circuit variations, maybe more? The famous evh amp had 820R//680n on the first stage but I'm not sure if that was ever a factory config, but who knows with Marshalls ambivalence to part values
That isn't quite right is it? Thanks for pointing that out for me; I stand corrected.
My brain for some reason failed to take into account the difference in gain and just saw the filtering side of things without taking into account the effect of the different resistor values. One has more gain at a higher cut-off and the other less gain at a lower cut-off. So I imagine the actual tonal response would be similar. I need to find one of those online calculators to satisfy my curiosity now.
One thing is, don't use the amp with the SV112 cab as that single 12" enclosure is not great at all as I kind of expected, use a 2x12.
And...........it retails at $995, not a good look and well overpriced. A classic case of aesthetics over usefulness and efficiency.
Optical wrote: ↑Sun Jan 01, 2023 12:31 pmThe 820R value is thicker/more bass/less treble shelving than the 2k7 but yeah
I believe the 820R/680nf was featured in the early Marshalls with the split cathode arrangement before they went to the more common 2.7k/680nf arrangement. The 820R/680nf rolls off the lower frequencies from 285Hz downwards and 2.7k/680nf from around 86Hz.
No that's not quite right.. the resistor sets the unbypassed gain, lower values are more gain.
There's about 12 different superlead circuit variations, maybe more? The famous evh amp had 820R//680n on the first stage but I'm not sure if that was ever a factory config, but who knows with Marshalls ambivalence to part values
This . And the bypass cap allows certain frequencies thru as is there is no resistor. Those frequencies get even more amplified by the stage!