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Projects => Build Reports => Topic started by: Hexjibber on March 29, 2020, 10:10:00 AM

Title: Coda Effects Black Hole
Post by: Hexjibber on March 29, 2020, 10:10:00 AM
Seem to be spending more time indoors of late here in the UK for some reason so I'm rattling through the builds!

Here's a Sunn Model T preamp from Benoit at Coda Effects. Has some nice crunchy overdriven tones and you can dime the gain and let rip into some sludge doom! I also tried a Rat before it because SunnO))) and is probably what a lot of people associate with the amp that the pedal is based on. I played a chord for 4 minutes and 42 seconds whilst meditating on humanity's inexorable decline into chaos so I think it works as intended!

Reverse etched and painted black then I found this cool 'hologram' glitter spray for some added cosmic vibes!

(https://66.media.tumblr.com/dabef3559d495fe749bcdd7459abb7ff/a91cac7d7ac13349-a0/s1280x1920/c0b51a03311deb0253335e3306f8ae459a409173.jpg)

(https://66.media.tumblr.com/b89df85c76a375225fc462ca5a563b0c/a91cac7d7ac13349-77/s1280x1920/5fbe571f61926017e31807143acf3009d0a2126d.jpg)

(https://66.media.tumblr.com/45a10c94f81d1db61e4cfeb5b6697972/a91cac7d7ac13349-0c/s1280x1920/14d1bb9e65b34359303c68951f887cdbe1e02454.jpg)

(https://66.media.tumblr.com/9e9e816b18f709b5cb9c55e0a5dc9d56/a91cac7d7ac13349-52/s1280x1920/f70dc1ac8a56cb20fa6b71ad1f15410e792f7408.jpg)


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Title: Re: Coda Effects Black Hole
Post by: Drew Hallenbeck on March 29, 2020, 10:12:24 AM
Love that etch! And the finish with the sparkle paint is top notch!
Title: Re: Coda Effects Black Hole
Post by: m-Kresol on March 29, 2020, 10:16:24 AM
Noice!

good to have you back
Title: Re: Coda Effects Black Hole
Post by: Caedarn on March 29, 2020, 02:09:52 PM
Awesome - really beautiful!
Title: Re: Coda Effects Black Hole
Post by: Timko on March 29, 2020, 05:51:17 PM
YES!  That is a beautiful etch man.  Well done.  Good paint choice to boot.
Title: Re: Coda Effects Black Hole
Post by: Bio77 on March 29, 2020, 06:45:30 PM
That's crazy awesome, love it!
Title: Re: Coda Effects Black Hole
Post by: benny_profane on March 29, 2020, 06:57:50 PM
That's a really fun project and that turned out great for you! Thanks for sharing!
Title: Re: Coda Effects Black Hole
Post by: mjg on March 29, 2020, 08:54:51 PM
Whoah, cosmic!    8)

That's a very good etch.
Title: Re: Coda Effects Black Hole
Post by: dawson on March 29, 2020, 11:27:19 PM
This build is truly spectacular- it may even be perfect.
What are you going to do, now that there's no room left for improvement??
Title: Re: Coda Effects Black Hole
Post by: Hexjibber on March 30, 2020, 06:41:49 AM
Thanks everyone, really happy with the end result of this one. More to come, got a looooong list of builds I want to get through!


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Title: Re: Coda Effects Black Hole
Post by: cooder on March 30, 2020, 08:05:25 AM
Spiffin' and sparkling sharp as! Looking forward to seeing more of that looooong list to come!
Title: Re: Coda Effects Black Hole
Post by: Aentons on March 30, 2020, 02:38:59 PM
That sparkle is kick ass
Title: Re: Coda Effects Black Hole
Post by: Philthy on April 01, 2020, 03:41:41 AM
Outstanding
Title: Re: Coda Effects Black Hole
Post by: (DEAD)fx on April 08, 2020, 04:51:50 PM
looks sharp as hell! great work!
Title: Re: Coda Effects Black Hole
Post by: Hexjibber on April 08, 2020, 10:09:25 PM
Thanks guys, appreciate it!


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Title: Re: Coda Effects Black Hole
Post by: selfdestroyer on May 04, 2020, 11:35:09 PM
Damn your on a roll this month!

Great job
Title: Re: Coda Effects Black Hole
Post by: Hexjibber on May 06, 2020, 02:47:41 PM
Quote from: selfdestroyer on May 04, 2020, 11:35:09 PM
Damn your on a roll this month!

Great job

Cheers Cody!  8)
Title: Re: Coda Effects Black Hole
Post by: benny_profane on June 17, 2020, 04:10:13 AM
I keep coming back to this build. Such a fantastic job with the finish!

I was looking at the schematic and had a question:
Q4 before the tonestack is a common drain amplifier. I'm not terribly familiar with the biasing here. There's no gain resistor and there's a static source resistor. If the circuit were to be adapted to run at 18v, how would that biasing need to be changed?

(https://4.bp.blogspot.com/-D6inZrGI75w/Whx10_gxOxI/AAAAAAAAE8A/Qjntz3_fRUQ_uqHKsBbFt2MT2nwWV6HRACLcBGAs/s1600/Sunn-Model-T-preamp.gif)
Title: Re: Coda Effects Black Hole
Post by: SirEgno on June 17, 2020, 06:43:20 AM
Looking at the original schematic  (http://www.prowessamplifiers.com/schematics/post/sunn_model_t.pdf) the 4th triode is (I don't know the correct word here... biased?) at the same way. 100k resistor on the cathode. maybe it's a coincidence...
My question is about the "anode" trimmers. is 20k enough? I've alway seen 100k trimmers on fet drain.

Now the real important thing. This build is awesome! The graphic gives a 3d look at the pedal.
Title: Re: Coda Effects Black Hole
Post by: diablochris6 on June 17, 2020, 04:25:28 PM
Love that enclosure design/paint job! It's insane that you got such ripping tones without the transistors soldered in...
Title: Re: Coda Effects Black Hole
Post by: Hexjibber on June 17, 2020, 05:00:40 PM
Quote from: diablochris6 on June 17, 2020, 04:25:28 PM
Love that enclosure design/paint job! It's insane that you got such ripping tones without the transistors soldered in...
Haha! I managed to get these super rare invisible ones, to say they have the mojo factor would be an understatement! Very hard to come by owing to the fact you can't see them, getting the orientation right was tricky to say the least!


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Title: Re: Coda Effects Black Hole
Post by: Hexjibber on June 17, 2020, 05:01:40 PM
Quote from: SirEgno on June 17, 2020, 06:43:20 AM
Now the real important thing. This build is awesome! The graphic gives a 3d look at the pedal.

Thanks!


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Title: Re: Coda Effects Black Hole
Post by: Hexjibber on June 17, 2020, 05:03:09 PM
Quote from: benny_profane on June 17, 2020, 04:10:13 AM
If the circuit were to be adapted to run at 18v, how would that biasing need to be changed?

I have to confess I have not even the slightest idea! Maybe a question for Benoit over at Coda Effects?


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Title: Re: Coda Effects Black Hole
Post by: benny_profane on June 17, 2020, 05:08:22 PM
Quote from: Hexjibber on June 17, 2020, 05:03:09 PM
Quote from: benny_profane on June 17, 2020, 04:10:13 AM
If the circuit were to be adapted to run at 18v, how would that biasing need to be changed?

I have to confess I have not even the slightest idea! Maybe a question for Benoit over at Coda Effects?


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I remember asking awhile back and he said to just be sure the caps were rated accordingly. The other JFETs have bias trimmers, so no problem there—just a little outta depth with the common drain biasing.
Title: Re: Coda Effects Black Hole
Post by: jazzster on May 05, 2021, 04:56:26 AM
Hello. I am currently working on a Black Hole build and I am having an issue.

The main part of the pedal works perfectly but the issue I'm having is that the boost section is not working. I have it wired to a 3PDT footswitch as well as an LED. I also turned the 100k boost trimpot into an external pot with a knob. When I hit the footswitch for boost, the LED turns on but all sound cuts out. The other weird thing is that as I turn up the 100k pot the LED will dim.

If you have any ideas on what may be wrong I would really appreciate it. Cheers.
Title: Re: Coda Effects Black Hole
Post by: m-Kresol on May 06, 2021, 04:06:18 PM
Quote from: jazzster on May 05, 2021, 04:56:26 AM
Hello. I am currently working on a Black Hole build and I am having an issue.

The main part of the pedal works perfectly but the issue I'm having is that the boost section is not working. I have it wired to a 3PDT footswitch as well as an LED. I also turned the 100k boost trimpot into an external pot with a knob. When I hit the footswitch for boost, the LED turns on but all sound cuts out. The other weird thing is that as I turn up the 100k pot the LED will dim.

If you have any ideas on what may be wrong I would really appreciate it. Cheers.

Hi Jazzter,

sounds like a wiring issue with your 3pdt. from your description it sounds like you may have grounded your out- or input. the fact that the led is interactive with the pot suggests that you're loosing supply voltage somehow

I'd suggest you open a tech-help thread with clear pictures of your build and a few details. If you follow the guidelines in the tech-help section you'll likely find the culprit already. If not, we'll try to help for sure.
Title: Re: Coda Effects Black Hole
Post by: jazzster on May 06, 2021, 10:47:55 PM
Ok sounds good. I put everything into the Tech Help page. Very new to the forum thing.
Title: Re: Coda Effects Black Hole
Post by: jazzster on May 08, 2021, 04:38:30 AM
SOLVED. Matmosphere helped me out. I just had my boost switch wired incorrectly.