Hi,
I have been intriged about the Artemus tone stack and volume control since I had a look at the pictures available online
http://ivanrichards.com.au/2011/06/18/a ... mplifiers/
http://www.fatsoundguitars.com/store/am ... 103152736/
I have tried to trace it without success, mostly because of the volume control, which seems to me to work in the opposite direction. I would like to know if it is a trick to avoid excessive loading on the cascode. Is someone else intrigued as well?
Regards
Carr Artemus volume control
Moderators: pompeiisneaks, Colossal
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Darkbluemurder
- Posts: 584
- Joined: Tue Jan 03, 2006 7:28 pm
Re: Carr Artemus volume control
I was intrigued by that amp as well.
As regards the tone controls the bass control could be a cap paralleled with a variable resistor. I don't think it's like Matchless Clubman or Chieftain since they do load the first gain stage considerably. The mid switch is probably similar to the Chieftain mid control, only it's a switch. This type of control has less insertion loss than the Ghia or Stang Ray control (I tried the Stangray tone control and the Chieftain mid controls in the same amp). Treble control could be a simple high cut.
On the AX84 website there is the Comanchero (in the Associated Projects section) whose tone controls were designed to have the least possible insertion loss. They may not be simply transferable to the Artemus because the Artemus has only one preamp stage whereas the Comanchero has three.
Cheers Stephan
As regards the tone controls the bass control could be a cap paralleled with a variable resistor. I don't think it's like Matchless Clubman or Chieftain since they do load the first gain stage considerably. The mid switch is probably similar to the Chieftain mid control, only it's a switch. This type of control has less insertion loss than the Ghia or Stang Ray control (I tried the Stangray tone control and the Chieftain mid controls in the same amp). Treble control could be a simple high cut.
On the AX84 website there is the Comanchero (in the Associated Projects section) whose tone controls were designed to have the least possible insertion loss. They may not be simply transferable to the Artemus because the Artemus has only one preamp stage whereas the Comanchero has three.
Cheers Stephan
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publicroman
- Posts: 3
- Joined: Wed Feb 06, 2013 8:10 pm
Re: Carr Artemus volume control
Thanks for chiming in.
Actually, the bass tone stack per se is pretty simple, like two coupling caps in parallel and one of them in series with the pot. And the treble must be a cut control, there is almost no other possibility. But it is the volume and its relation to the bass control what really puzzles me. I am almost sure that the design goal was to be able to scoop the mids (for a more fendery sound) without loading the probably high output impedance cascode.
Funny you mention the comanchero. Was my first build (not that long ago) and I tweaked the circuit up and down, the tone stack most of all. But somehow the initial design constraints on that amp didn't allow me to get the sound my whimsical ear was asking for. Very fun amp to build and play, anyway.
Back to topic, I am planning to experiment with cascodes, which theoretically aren't that good idea, even less with a 12ax7, but the Artemus sounds killer to me, and so the search goes on.
Actually, the bass tone stack per se is pretty simple, like two coupling caps in parallel and one of them in series with the pot. And the treble must be a cut control, there is almost no other possibility. But it is the volume and its relation to the bass control what really puzzles me. I am almost sure that the design goal was to be able to scoop the mids (for a more fendery sound) without loading the probably high output impedance cascode.
Funny you mention the comanchero. Was my first build (not that long ago) and I tweaked the circuit up and down, the tone stack most of all. But somehow the initial design constraints on that amp didn't allow me to get the sound my whimsical ear was asking for. Very fun amp to build and play, anyway.
Back to topic, I am planning to experiment with cascodes, which theoretically aren't that good idea, even less with a 12ax7, but the Artemus sounds killer to me, and so the search goes on.
Re: Carr Artemus volume control
Why do you think it works backwards? The yellow wire is ground.....unless Im missing something.publicroman wrote:Hi,
I have been intriged about the Artemus tone stack and volume control since I had a look at the pictures available online
http://ivanrichards.com.au/2011/06/18/a ... mplifiers/
I have tried to trace it without success, mostly because of the volume control, which seems to me to work in the opposite direction. I would like to know if it is a trick to avoid excessive loading on the cascode. Is someone else intrigued as well?
Regards
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publicroman
- Posts: 3
- Joined: Wed Feb 06, 2013 8:10 pm
Re: Carr Artemus volume control
You are quite right, my bad. But I still would like to know if someone knows of something similar. I would try again to trace the circuit later.Cameron wrote: Why do you think it works backwards? The yellow wire is ground.....unless Im missing something.