pentode/triode deficiency

[t2mike2]

But guys really consider, with the removal of the second gain control circuit wise nothing has even been added or taken away. It really is as simple as putting a pot there. They fixed the drive value at 7.5. Im sure you all know that a potentiometer acts as nothing more than a variable resistor.
He got rid of it and fixed it at one value. but there is no circuit design involved in that at all. they read the resistance at 7.5 on the drive pot and dropped in a resistor of that value. Very very simple.

I just wish they hadn't.

~mike~

 

[DaveDaveDave]

Mike, just to be clear - they fixed the input gain at 7.5, and the gain on the Mark V acts like the gain on the Mark IV... at least according to the manual. I know, I know, that's still going to bug you a lot. I hear ya, I miss the gain pot too - but not in a really practical way, but take a look at this if you will:
http://www.tubefreak.com/mk4-1.gif
Sure, there's a hair of flexibility lost - but it really is only a hair. but the pots are pretty much stacked up, what with pots being logaritmic. With the Mark IV gain pot on 10, it may as well no even be there. Like the previous poster said - maybe this isn't the amp for you. It's pretty obvious that Mesa was trying to combat a lot of complaints about earlier Mark amps being to difficult to dial in. Sounds like you need a lot more cash so that you can have your own custom amp built. I'm sure your Mark V could be mod'd too - but everything has it's price

Cheers,
Dave

But guys really consider, with the removal of the second gain control circuit wise nothing has even been added or taken away. It really is as simple as putting a pot there. They fixed the drive value at 7.5. Im sure you all know that a potentiometer acts as nothing more than a variable resistor.
He got rid of it and fixed it at one value. but there is no circuit design involved in that at all. they read the resistance at 7.5 on the drive pot and dropped in a resistor of that value. Very very simple.

I just wish they hadn't.

~mike~

 

[bradg]

I only used the pent/tri switch on the lead channel anyway. Mark V layout works for me. 8)

 

[t2mike2]

Yeah i have basically realized that my perfect amp doesn't exist. The perfect amp would be Mark III clean and Early VHT Classic 100 (except brand new) Lead in a Sig :X control format.

I was hoping the Mark V would be close enough. And honestly despite the lack of a few features it still rocks, and im tired of tone searching.


The extra control would rock. But as you said it is not an end of the world type of ommission.

And yeah youre right, my perfect amp would cost alot more.
--

on the upside, it was very very very smart of randall to include a 10 watt mode.

VEry very very smart.

~mike~

 

[t2mike2]

Mike, just to be clear - they fixed the input gain at 7.5, and the gain on the Mark V acts like the gain on the Mark IV... at least according to the manual. I know, I know, that's still going to bug you a lot. I hear ya, I miss the gain pot too - but not in a really practical way, but take a look at this if you will:
http://www.tubefreak.com/mk4-1.gif
Sure, there's a hair of flexibility lost - but it really is only a hair. but the pots are pretty much stacked up, what with pots being logaritmic. With the Mark IV gain pot on 10, it may as well no even be there. Like the previous poster said - maybe this isn't the amp for you. It's pretty obvious that Mesa was trying to combat a lot of complaints about earlier Mark amps being to difficult to dial in. Sounds like you need a lot more cash so that you can have your own custom amp built. I'm sure your Mark V could be mod'd too - but everything has it's price

Cheers,
Dave



~mike~

[/quote]
So are you basically telling me here, that the drive pot acted as simply like, an input level control. or in other words a volume trim to match the output of your guitar. As in , i could get similar results by using an eq pedal before or after to boost or cut my overall input signal?
thanks for the schematic by the way.

 

[DaveDaveDave]

Mike, just to be clear - they fixed the input gain at 7.5, and the gain on the Mark V acts like the gain on the Mark IV... at least according to the manual. I know, I know, that's still going to bug you a lot. I hear ya, I miss the gain pot too - but not in a really practical way, but take a look at this if you will:
http://www.tubefreak.com/mk4-1.gif
Sure, there's a hair of flexibility lost - but it really is only a hair. but the pots are pretty much stacked up, what with pots being logaritmic. With the Mark IV gain pot on 10, it may as well no even be there. Like the previous poster said - maybe this isn't the amp for you. It's pretty obvious that Mesa was trying to combat a lot of complaints about earlier Mark amps being to difficult to dial in. Sounds like you need a lot more cash so that you can have your own custom amp built. I'm sure your Mark V could be mod'd too - but everything has it's price

Cheers,
Dave



~mike~

So are you basically telling me here, that the drive pot acted as simply like, an input level control. or in other words a volume trim to match the output of your guitar. As in , i could get similar results by using an eq pedal before or after to boost or cut my overall input signal?
thanks for the schematic by the way.[/quote]

Yes, and no - so very close this time! you've got the function right, but it was labeled GAIN on the Mark IV. In the V, that's gone, as you say, and the knob previously labeled DRIVE is now called GAIN.

Similar results, yes. Of course, the fixed 7.5 input gain is after the first 1/2 of V1, and served to overdrive the following tube stages. You can alway dump more a LOT more input into V1 before overdriving it, cuz we're starting off with such a tiny (pickup) signal to begin with. The first gain stage in any amp just converts the millivolt/current based pickup signal into the ballpark of output voltage for the subsequent gain stages. All these gain stages work exponentially, so small changes up front have major changes down the line.

Here's something else you might find interesting - boy, I had to dig deep in my delicious bookmarks for this one:
http://www.harmony-central.com/Guitar/guitar-amp-evolution.html

Also, that was only a tiny part of the Mark IV schematic - here's all 4 pages:
http://www.tubefreak.com/schema.htm#mark4

BTW, after all this - my next amp is a Trainwreck Express clone for Ceriatone! More tube magic!

Cheers!

Dave

 

[DaveDaveDave]

Mike, just to be clear - they fixed the input gain at 7.5, and the gain on the Mark V acts like the gain on the Mark IV... at least according to the manual. I know, I know, that's still going to bug you a lot. I hear ya, I miss the gain pot too - but not in a really practical way, but take a look at this if you will:
http://www.tubefreak.com/mk4-1.gif
Sure, there's a hair of flexibility lost - but it really is only a hair. but the pots are pretty much stacked up, what with pots being logaritmic. With the Mark IV gain pot on 10, it may as well no even be there. Like the previous poster said - maybe this isn't the amp for you. It's pretty obvious that Mesa was trying to combat a lot of complaints about earlier Mark amps being to difficult to dial in. Sounds like you need a lot more cash so that you can have your own custom amp built. I'm sure your Mark V could be mod'd too - but everything has it's price

Cheers,
Dave



~mike~

So are you basically telling me here, that the drive pot acted as simply like, an input level control. or in other words a volume trim to match the output of your guitar. As in , i could get similar results by using an eq pedal before or after to boost or cut my overall input signal?
thanks for the schematic by the way.[/quote]

Yes, and no - so very close this time! you've got the function right, but it was labeled GAIN on the Mark IV. In the V, that's gone, as you say, and the knob previously labeled DRIVE is now called GAIN.

Similar results, yes. Of course, the fixed 7.5 input gain is after the first 1/2 of V1, and served to overdrive the following tube stages. You can alway dump more a LOT more input into V1 before overdriving it, cuz we're starting off with such a tiny (pickup) signal to begin with. The first gain stage in any amp just converts the millivolt/current based pickup signal into the ballpark of output voltage for the subsequent gain stages. All these gain stages work exponentially, so small changes up front have major changes down the line.

Here's something else you might find interesting - boy, I had to dig deep in my delicious bookmarks for this one:
http://www.harmony-central.com/Guitar/guitar-amp-evolution.html

Also, that was only a tiny part of the Mark IV schematic - here's all 4 pages:
http://www.tubefreak.com/schema.htm#mark4

BTW, after all this - my next amp is a Trainwreck Express clone for Ceriatone! More tube magic!

Cheers!

Dave

 

[MrMarkIII]

I'll bet they talked to a bunch of real-world players who told them the Mark IV's separate Gain and Drive controls were redundant at best.

 

[rabies]

I'll bet they talked to a bunch of real-world players who told them the Mark IV's separate Gain and Drive controls were redundant at best.

+1. it's too fine-grained and unnecessary to have both.

play yer gtar, not tweek the amp...

 

[primal]

I really think i'd have to side with the OP on this. In my mind there really is no excuse of intentionally leaving features out for the sake of authenticity, or quirkyness.

...

2) Fx loop not assignable to multipe channels. He did it on the roadster and roadking. There really is no reason it should be on the mark v. You can assign it to ONE channel. But if you want to instantly switch between multiple channels with the fx still on, then you are stuck double footswitching, ..,. which i loathe.

He did it on the Mark IV as well, though the controls are a little confusing.

That one will annoy me a bit. But it definately isn't a deal breaker