How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

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davemojo
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Re: How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

Post by davemojo »

Hi Bjorn

So if you check the power inlet is slightly different from usual one same for the power switch.

Power switch has 4 lugs
Power inlet has a bridged connection on the side and the typical 3 lugs on the right side of the photo middle one must be ground.

On the Tube-Town layout they bring Blue and Blue both to power switch.
On my PT is Black N and Blue 230V so far so good

So I bring black to the right bottom lug?
And blue to the power inlet, which lug bottom or top one? since middle one is ground...

At this point I probably need to bring down another wire from left bottom power switch down to the power inlet other lug?

So following your wiring advise top lugs on power switch in this case will not be used correct?

Check photos please
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Re: How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

Post by Bieworm »

Screenshot_20210508-104558_Adobe Acrobat.jpg
Davide..here's a wiring layout I'd recommend. Figure out what wire is which color ( I refer to my earlier notes on your photo)
About the double switch.. it's the same as 2 single switches next to each other.. only they're switched with 1 toggle. So the connections should be vertical... not horizontal. Check with a DMM for continuity to be sure.
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Re: How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

Post by davemojo »

Bieworm wrote:
Sat 05/08/21 3:51 am
Screenshot_20210508-104558_Adobe Acrobat.jpgDavide..here's a wiring layout I'd recommend. Figure out what wire is which color ( I refer to my earlier notes on your photo)
About the double switch.. it's the same as 2 single switches next to each other.. only they're switched with 1 toggle. So the connections should be vertical... not horizontal. Check with a DMM for continuity to be sure.
Ok that is how I am doing mine, got it yes I understand, and I trust your experience, since you are being doing this probably for long time, but...what would be the benefit between wiring this way and wiring the way Tube-Town did it?

I am not saying anything :-) that criticize the Modern Classic trying to understnad the logic behind

so far I have seen 3 ways to do it, Stewmac, Tube-Town, and Josh schematic, and Stewmac , not just the wiring but the entire Stewmac layout is crap no doubts, I understand it now.

What instead at least the wiring part, between Josh one and Tube-Town there are similitudes on how overall is made, the wiring is different, at least the parts being discussed here but I can't see a huge impact or benefits on doing one or the other.

Resistors are on both metal film, the overall layout build is much simplified compared with the obsolete StewMac style, I bet the Josh layout (Technically Speaking) is superior, in fact I am building both, hopefully will succeed in both at first go this time, will definately take my time eve if it will take long time, and I wanna test both sounds, I know they are different products I am expecting different sound.

The StewMac has a lots of hum, it works fine now but isn't brilliant, surely has to do with soldering, resistors being used, but anyway I want to succeed on making amps I like it and enjoy it hurray
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Re: How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

Post by Bieworm »

Wiring up the power supply can be confusing. That's why I recommend the JMPGuitars way. Not saying the tubetown layout is wrong.. it's too wire-y for my taste.
You clearly suffer from the amp building bug... haha
Be prepared you're going to have to troubleshoot anyway 😉
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Re: How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

Post by davemojo »

Bieworm wrote:
Sat 05/08/21 10:54 am
Wiring up the power supply can be confusing. That's why I recommend the JMPGuitars way. Not saying the tubetown layout is wrong.. it's too wire-y for my taste.
You clearly suffer from the amp building bug... haha
Be prepared you're going to have to troubleshoot anyway 😉
I thank you very much for your help.
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Re: How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

Post by davemojo »

Hey Morning Biorn

You mentioned on the wiring photo suggestion to cut short the orange and seal it off with heat shrink tube and to twist together the brown gray wires, would they also need to be shortened and sealed off with heat shrink tube? Since they aren’t used?

Thanks
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Re: How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

Post by Bieworm »

davemojo wrote:
Sun 05/09/21 12:27 am
Hey Morning Biorn

You mentioned on the wiring photo suggestion to cut short the orange and seal it off with heat shrink tube and to twist together the brown gray wires, would they also need to be shortened and sealed off with heat shrink tube? Since they aren’t used?

Thanks
The orange is not used. The grey and brown should be connected to each other. They connect 2 x 120V bobbins in series to create 230 or 240V primary.. depending on connecting the blue or white wire. So
1. Cut short the orange and seal it off
2. Cut short the grey and brown, strip the ends, tin them together and seal them off. You can also make the connection on a dedicated terminal.
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Re: How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

Post by davemojo »

Hey All

I do Exactly know where OT wires for impendence go?

I suppose Yellow 4 Ohm on number 1 Green 8 Ohm on Number 2 and Orange 16 Ohm on number 3?
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Re: How to fit and attach an 18 Watts chassis on a Combo or Head Enclosure

Post by JMPGuitars »

davemojo wrote:
Tue 05/11/21 7:59 am
Hey All

I do Exactly know where OT wires for impendence go?

I suppose Yellow 4 Ohm on number 1 Green 8 Ohm on Number 2 and Orange 16 Ohm on number 3?
It doesn't matter as long as 8ohm is in the middle, and you know which is which. If you have a panel made with the numbers written, then you need to match that.
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