Uncle GAS Needs You: Help Design an All Tube Amp!!!

[JacksonAmpworks]

I'm not sure if this is right, but i was thinking about this earlier. Don't you actually get a mid boost when you cut the treble and bass in this type of set-up? I viewed it as a conservation of volume type deal where if one frequency is cut, some other is boosted. Am i on the right track or am i de-railed completely?

You're dead on! The Baxandall is really cool in that if you cut the Bass and Treble controls, you get a great Mid boost as pictured here.

Also, when you raise the Bass and Treble controls, you get a really nice Mid cut as pictured here:

Check the following performance charts. First moving the bass control through 0, 2.5, 5, 7.5, and 10 with treble at 5. Below, moving the treble control through its range whilst keeping the bass at 5:

To me this honestly eliminates the need for a Mid control as any other Mid control that I would include would not have the same ammount of authority as the "mid" control that is already built in.

I think adding switches for Ultra-Hi and Ultra-Lo would round it out and make it very flexible.

Your thoughts?

 

[Fretless5verfan]

You're Dead on!...

To me this honestly eliminates the need for a Mid control as any other Mid control that I would include would not have the same ammount of authority as the "mid" control that is already built in.

I think adding switches for Ultra-Hi and Ultra-Lo would round it out and make it very flexible.

Your thoughts?

I'm glad i didn't make an a$$ out of myself with that one

I think with the ultra-low and ultra-hi added i'd have everything i need for flexability. So you got my vote for it

 

[JacksonAmpworks]

FWIW:

Seems many 2 channel amps I've seen have a bass/treble for clean and mids thrown in for lead - I assume there's a reason for that. From experience, well designed bass/treble controls don't need a mid. I think what will matter is the sound that results and not the controls to get you there. To me, the less tweaking to get tone, the better. Also seems to be a lot of passive control for tube bass amps. I don't know if something like a push/pull mid engage/disengage thing is a possibility or not but, if so, a compromise for thought maybe. To my ears, you can't adjust any band without it affecting another. One of my SS amps with active controls clearly boosts trebles in the process of boosting bass - fine by me becuase it becomes clearer rather than muddy.

Well on guitar amps, the clean channel is pretty easy to EQ, just set the treble where you want it and add bass to taste. The Mid control becomes useful on the gain channels as some guys may want to scoop the mids etc. One of the REALLY cool things about the Baxandall is that the two controls are COMPLETELY independant of each other. When you raise the bass, the treble remains constand and vice versa for the treble control. It's really simple, flexible and user friendly.

Since design/construction aspect is out of my league and I've only witnessed what's transpired from the grandstands, the self-names that arose to me were along the lines of: Talkbass, Forum 300, Forum 123, TB 123 - something along those lines. The 300 and 123 refering to output. I assume the length of the name is a factor in cost (always a consideration) and that, like want adds, the more words the more coin. So I guess the shorter the better. I doubt anybody who would buy a 3k amp is going to give much consideration to the name - at least I hope not. The manufacturer they're going to seriously consider.

Honestly, lenght is no consideration. Finding a name that is cool and that communicates the character of the amp is what's really hard to find. How about "Buttercup"?

 

[JacksonAmpworks]

I'm glad i didn't make an a$$ out of myself with that one

I think with the ultra-low and ultra-hi added i'd have everything i need for flexability. So you got my vote for it

Yeah I'm kinda leaning toward the Baxandall for both channels with the Ultra switches included on each channel.

 

[JacksonAmpworks]

The mid control adds flexibility, but would compromise a pure B15 tone. Could the mid control be switched in and out (to offer the best of both worlds)?

I think you're right. That's why I think that the Baxandal as it is, is perfect for this amp. There is a "hidden" mid control already in the Baxandall. See previous post.

 

[Fretless5verfan]

Yeah I'm kinda leaning toward the Baxandall for both channels with the Ultra switches included on each channel.

That'd work for me.

So you're nixing the resonance and presence controls all together?

 

[JacksonAmpworks]

I'd leave the mid control off the "clean" channel, but have one on the other. I know a lot of guys here like to be able to tweak everything but with a Baxandall tone stack, just two bands really ARE better sounding. That's part of the B15 tone and you will lose that if you include a midrange control.

I'm probably going to leave the tone stacks straight Baxandall's on both channels with the Ultra-Hi and the Ultra-Lo on each channel. On channel 2 I may add a Mid Shift control to fles that one up a bit. We'll see!

 

[JacksonAmpworks]

As for the SVT channel option, I like your idea of adding a seperate master volume control. My main gripe with vintage SVT's is that their best tone (IMHO) doesn;t kick in unless you run them at least 75% wide open, meaning that I found myself struggling to get a good tone at lower volumes. Of course, the 100w/200w/300w option will help, but I like the ability to control gain and volume seperately.

You really have to add a Master to this channel if you want to crank it. As it stands now, this channel should have plenty of gain to get some decent OD tones without going over the edge.

Oh, and two more names for you: "Kong" which I think might be even more appropriate if there werent' another remake in the works (though I am hopeful that Peter Jackson will do another great job), or "The Double Triple." This relates to both the two banks of three tubes, and the two channels modeled after three character named amps (B-15 and SVT).

As far as names, I really like one name titles as they seem to have more punch. Please keep the name ideas coming, as they really do help!

 

[JacksonAmpworks]

That'd work for me.

So you're nixing the resonance and presence controls all together?

Not at all! They are still there and are "Global" controls for the entire amp.

Here are the controls as I see them today:

Channel 1

Volume​

Treble​

Bass​

Ultra-Lo and Ultra-Hi Switches​

Channel 2

Volume​

Treble​

Bass​

Ultra-Lo and Ultra-Hi Switches​

Master​

Global Controls

Resonance​

Presence​

 

[Fretless5verfan]

Not at all! They are still there and are "Global" controls for the entire amp.

Here are the controls as I see them today:

Channel 1

Volume​

Treble​

Bass​

Ultra-Lo and Ultra-Hi Switches​

Channel 2

Volume​

Treble​

Bass​

Ultra-Lo and Ultra-Hi Switches​

Master​

Global Controls

Resonance​

Presence​

Oh man, i like that layout... a lot!

Ok, Here is THE best name i could think of....

"The Peacemaker"

I think it's more badass than "The Pacific" and "The Diamondback" combined. Plus it's the gun that won the west....right? This'll be the amp that kills the rest

 

[Biker4Him]

As far as names, I really like one name titles as they seem to have more punch. Please keep the name ideas coming, as they really do help!

BEHEMOTH

 

[JacksonAmpworks]

Oh man, i like that layout... a lot!

Ok, Here is THE best name i could think of....

"The Peacemaker"

I think it's more badass than "The Pacific" and "The Diamondback" combined. Plus it's the gun that won the west....right? This'll be the amp that kills the rest

The only problem is that there is an amp already called the Peacemaker. That might upset them just a bit. Good instinct though!

 

[JacksonAmpworks]

BEHEMOTH

I like! I like!

 

[Fretless5verfan]

The only problem is that there is an amp already called the Peacemaker. That might upset them just a bit. Good instinct though!

Really? I've never heard of that one...whoever named it had great taste though

 

[JacksonAmpworks]

Really? I've never heard of that one...whoever named it had great taste though

Great minds think alike!

 

[DEVILMAN]

For a name, how 'bout "Mastodon 622". The "622" for 6pwr tubes, 2pre tubes & 2 channels...just a thought...


cheers,
~S~

 

[tombowlus]

A couple of thoughts. It's your amp, Brad, and I think it is coming together really nicely. But, if I were to get my complete "wish list", I'd also love to see the EQ bypass switch (at least for the 6SL7 channel), the ability to blend some clean low frequencies in with my overdriven tone, and a variable (at least two settings) damping factor control. Of course, I'd hate to end up being like Homer Simpson (D'oh!), so I throw these ideas out for you to use - or discard - at your discretion.

As for a Midrange control, I do like a tone that is balanced through the mids (I'm not a fan of either scooped mids or midrange "humps"), and I have found that if my cabs are fairly balanced through the mids, I don't need to mess with them. So while I have expressed some desire to see a midrange control with selectable frequencies for the "SVT side", my concern was just to be able to dial in/out mids to achieve a fairly balanced tone. If you can deliver that (with overdrive/distortion) from the 12AX7 channel without the need for a midrange control, then I'm cool with that.

Take care, Tom.

 

[Fretless5verfan]

A couple of thoughts. It's your amp, Brad, and I think it is coming together really nicely. But, if I were to get my complete "wish list", I'd also love to see the EQ bypass switch (at least for the 6SL7 channel), the ability to blend some clean low frequencies in with my overdriven tone, and a variable (at least two settings) damping factor control. Of course, I'd hate to end up being like Homer Simpson (D'oh!), so I throw these ideas out for you to use - or discard - at your discretion.

As for a Midrange control, I do like a tone that is balanced through the mids (I'm not a fan of either scooped mids or midrange "humps"), and I have found that if my cabs are fairly balanced through the mids, I don't need to mess with them. So while I have expressed some desire to see a midrange control with selectable frequencies for the "SVT side", my concern was just to be able to dial in/out mids to achieve a fairly balanced tone. If you can deliver that (with overdrive/distortion) from the 12AX7 channel without the need for a midrange control, then I'm cool with that.

Take care, Tom.

I thought the dampening was the resonance control? I have no idea what dampening does, so you'll have to excuse my mental handicap

That stuff is on my wishlist too, but if it can't be done or messes up the tone i'm totally cool with it.

 

[tombowlus]

I thought the dampening was the resonance control? I have no idea what dampening does, so you'll have to excuse my mental handicap

It may be. I have seen that same term - "resonance" - used for apparently different methods of altering the tone. If it is a damping factor control, then whoo hoo!

 

[jvb]

It may be. I have seen that same term - "resonance" - used for apparently different methods of altering the tone. If it is a damping factor control, then whoo hoo!

I'd like to hear what a 'resonance' control does as well. If I had to hazard a guess I would say it was a notch filter in the neg feedback in the output stage, but that's only a guess.

Which other amps have 'resonance' controls? I've seen wah-wahs with that but that's just a band-pass filter where the control varies the Q (peakedness?) of the filter.