Blues Briefcase
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- crgfrench
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Blues Briefcase
The final major components arrived from mouser
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Last edited by crgfrench on Sun 06/02/19 7:49 pm, edited 1 time in total.
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- crgfrench
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Re: Blues Briefcase
Mounted PT
attachment=0]20190602_110230.jpg[/attachment]
attachment=0]20190602_110230.jpg[/attachment]
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Last edited by crgfrench on Sun 06/02/19 7:53 pm, edited 1 time in total.
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Re: Blues Briefcase
Initial Layout
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- crgfrench
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Re: Blues Briefcase
Installed OT on chassis and drilled socket holes
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Re: Blues Briefcase
same OT as mine Craig,what primary resistance do you have for each plate wire from the centre tap?
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- crgfrench
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Re: Blues Briefcase
This one is 307 Ohms brown to red and 345 Ohms blue to red.geoff 1965 wrote: ↑Sun 06/02/19 5:23 pmsame OT as mine Craig,what primary resistance do you have for each plate wire from the centre tap?
The tap is at "half the windings" rather than "half the resistance".
For comparison, the Heyboer HT 6135 I used in my Denim Deluxe was:
305 Ohms brown to red and 324 Ohms blue to red.
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Re: Blues Briefcase
I'm going to cut a 9" diameter hole in the side of the briefcase and mount the Celestion Ten 30 directly to it with 4 bolts.
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Re: Blues Briefcase
I think so. I'm going to try it and find out. I seem to be capable of only learning things the hard way. If it's not sturdy enough I could easily add a birch ply or aluminum baffle.
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Re: Blues Briefcase
okay,i was thinking you could sandwich some mesh or grillcloth between the baffle & case to protect the speaker as well as strengthen it.
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Re: Blues Briefcase
Good idea, thanks. I'm mounting the Celestion on the inside, with this grille mounted on the outside:
https://www.parts-express.com/heavy-dut ... l--262-862
https://www.parts-express.com/heavy-dut ... l--262-862
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Re: Blues Briefcase
This is the schematic, it's a Fullerwell circuit.
I used a 125 Ohm bias resistor instead of the 250 listed here.
I used a 125 Ohm bias resistor instead of the 250 listed here.
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Last edited by crgfrench on Wed 07/03/19 7:04 am, edited 1 time in total.
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Re: Blues Briefcase
Here is the plangeoff 1965 wrote: ↑Mon 06/03/19 5:54 pmokay,i was thinking you could sandwich some mesh or grillcloth between the baffle & case to protect the speaker as well as strengthen it.
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Re: Blues Briefcase
so are you going to bond it to the outside of the case? if you cut the hole a bit smaller you could push it through from the inside and use a baffle to sandwich the rubber rim.i'm sure you'll get better resonance from the speaker with a ply baffle. it's your project so what do you think?
it means you will have to remove some of that "lovely" red fur!!You do not have the required permissions to view the files attached to this post.
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- JMPGuitars
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Re: Blues Briefcase
Here's my 2 cents:
Strip the lining on the inside of the briefcase. Add between 1/4" to 1/2" void-free plywood to the entire main panel that the speaker is being mounted on. Glue it on, and use weights on top and/or clamps to keep it pressed tight.
After that's done, drill the speaker mounting holes / speaker hole.
I would try to not cut out the tweed to the full size of the hole. If you can lift the tweed from the panel, and save an extra couple inches, you'll be able to wrap the tweed and cover the entire speaker hole edge.
This will give the speaker a much better sound than floating on a weak briefcase side. Also more stable for the rest of the stuff you're mounting.
Thanks,
Josh
PS. My wife made me do this:
Strip the lining on the inside of the briefcase. Add between 1/4" to 1/2" void-free plywood to the entire main panel that the speaker is being mounted on. Glue it on, and use weights on top and/or clamps to keep it pressed tight.
After that's done, drill the speaker mounting holes / speaker hole.
I would try to not cut out the tweed to the full size of the hole. If you can lift the tweed from the panel, and save an extra couple inches, you'll be able to wrap the tweed and cover the entire speaker hole edge.
This will give the speaker a much better sound than floating on a weak briefcase side. Also more stable for the rest of the stuff you're mounting.
Thanks,
Josh
PS. My wife made me do this:
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- crgfrench
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Re: Blues Briefcase
I cut the hole with a saber saw and mounted the Celestion on the inside and the grill on the outside with 4 through bolts. The briefcase is solid! I discovered it's 1/8" birch ply with the fur bonded to the inside and the tweed bonded to the outside. Same high quality solid construction as their tweed guitar cases. Will get some pix of the speaker when I get home from work.
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Re: Blues Briefcase
I don't recommend having less than 3/8" for a speaker baffle, and even that is on the thin side. Are you mounting the speaker on the same side as the circuit and transformers?
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- crgfrench
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Re: Blues Briefcase
Yes -- if you open the briefcase and turn it on its side it looks exactly like a combo setup, tubes sticking down from the chassis towards the speaker magnet. Like this pic:JMPGuitars wrote: ↑Fri 06/07/19 5:00 pmAre you mounting the speaker on the same side as the circuit and transformers?
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