Channel Switching

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AussieTim
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Channel Switching

Post by AussieTim »

Hi Guys
I have had some health issues throughout the last year which has put my 18watt project on the backburner, now I am starting to get better I am also looking to restart the build.
My question is why isn't there any layouts where there are channel switching as opposed to two separate channels just about all of my amps over many years have had foot-switching for the channels, so it seems archaic to not have it, I suppose I could also ask why have two jacks for high /low and not a switch there as well.
Is this due to snobbery/traditionalism or are there practical implications fro not having switching?
Tim
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TriodeLuvr
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Re: Channel Switching

Post by TriodeLuvr »

If I understand correctly, at least some of the functionality you're referring to requires small-signal relays. That creates a whole 'nother layer of complexity and cost due to circuit board mounting. That can be difficult to justify in one-off and small quantity builds. Then there's the aspect you point out regarding tradition. I just finished my first scratch build. It was tempting to include a lot of additional features, but I wanted to recreate the sound of the original as much as possible. Although I added an effects loop and reverb, the "straight-through" signal follows the Marshall 2104 topology almost exactly. That was important to me in bringing some assurance to the project of recreating the original tone and feel.

Jack
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Bieworm
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Re: Channel Switching

Post by Bieworm »

On my last build I took that next level step and implemented relays switching. That knowledge will definitely be applied in future builds. My channels are now footswitchable and panelswitchable. I love it. Took me some time figuring it out, but I knew zero about relays..
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Daviedawg
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Re: Channel Switching

Post by Daviedawg »

One point I have always implemented in my amps is to interfere with the signal as little as possible. This means one or two knobs per channel i.e. vol and tone. And when I have a need for channel switching I use an ABY box which allows mixing as well.
So it may be tradition but also keeping the signal as near as possible to the origin's output.

Dd
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Bieworm
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Re: Channel Switching

Post by Bieworm »

Some people like tradition. I don't really care..
Why drive without power steering... I like easy. That's why I love single channel amps. The tremolo TMB reverb is all a man needs...
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Re: Channel Switching

Post by JMPGuitars »

As Dd mentioned above, keeping the signal path simple / clean typically ensures better tone. The more complex the circuit gets, the more "tone suck" potential there is. Less stuff between the guitar and speaker is the idea.

With an ABY box (also as mentioned by Dd), you can have a simple enough channel switching setup if that's something you need.
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AussieTim
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Re: Channel Switching

Post by AussieTim »

Love this forum you guys really give good food for thought.
But isn't channel switching is merely a relay controlled AB box or am I missing something?
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Bieworm
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Re: Channel Switching

Post by Bieworm »

AussieTim wrote:
Sat 03/06/21 9:06 am
Love this forum you guys really give good food for thought.
But isn't channel switching is merely a relay controlled AB box or am I missing something?
I have to disagree here about using an ABY box. The wire lengths in the signal chain are a lot shorter with the relays switch. + it's less confusing with just an on-off footswitch. I find ABY boxes very confusing and since the channels are out of phase, the Y switching is absolutely useless.

Edit: ok stupid me. You're talking AB box.. not ABY.
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AussieTim
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Re: Channel Switching

Post by AussieTim »

I have noticed a mob called London power make channel switching relay boards as do Mojo
https://londonpower.com/electronics/ele ... relay-kit/
https://www.mojotone.com/amp-parts/Relay-Switching-Kits
Has anybody used these are they any good?
I am finalizing the design for my front panel so any input would be appreciated.
Be warned the next thing I will be asking is the who and where I should get my panels made
Tim
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Daviedawg
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Re: Channel Switching

Post by Daviedawg »

When I said what I do about switching I was just expressing my preference. I was not suggesting you should not do it your preferred way. That is why we build our own amps after all.

But on the plus side it saves extra inputs taking up space on the fascia.

Dd
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AussieTim
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Re: Channel Switching

Post by AussieTim »

Thanks DD I was thinking the same thing the project that I am building is a copy of the Trinity 18 watt with the V6 option as they call it which is switching between El 84 and 6V6 output tubes I have built and populated the Turret board bent up the chassis and gathered the components together, there is also a boost/fat switch, these are located under the chassis on the back of the amp which to my thinking would be a pain in the arse if you wanted to change the noise you are making mid song, therefore I was thinking of using the channel switch to free up some front panel space for these switches
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AussieTim
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Re: Channel Switching

Post by AussieTim »

Of course I could use a push pull switch on one of the volume knobs and have a childish chuckle with a pull fat label
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