Matchless Dirt Box | Part 2 : Doesn't Play Well With Others

[@danielsaturnino5715]

It does sound nice indeed.

[@elwrongo]

Interesting video, thanks. Not a sound I'd have a use for, kind of spikey and gritty and not what I'd be hoping a tube pedal would do. I have Mesa V-Twin that I really ought to sell for the same reason, its a high gain thing. I realise now what I'd like is a tube pedal that gets close to a warmed up Fender Princeton or some little EL84 amp on 6. Probably doesn't exist.

[@SkyscraperGuitars]

Looking forward to seeing the bypass circuit get installed... I have a feeling that will be a "yes" from the owner.

[@imannonymous7707]

Aww i had high hopes and expectations but i digress . I trust your ears man

[@russellhltn1396]

Wild guess on the tuner issue - the Dirtbox might be outputting a high-level ultrasonic signal that paralyzes the tuner.

[@johnwilliamson467]

Transformers are asymmetrical Try switch the primary leads to the transformer . I have measure much lower hum by doing that in pre-amps . Sating that it may in fact make it worse if you got luck and had the lower leak setup in place . Other than that it a major rework to go to star grounding . Rather odd that tube would not play well with others . This with out seeing the schematic . Good luck with that.

[@retread1083]

Strange indeed! What happens if the pedal is switched to bypass and its AC power is unplugged (and the filter caps discharged)? Will the signal pass through the tuner?

[@russellhltn1396]

Without seeing a schematic, I'm not sure how you can avoid a ground loop without disabling the safety ground. I'm thinking you'd have to isolate signal ground from the case and connect them with a 10 ohm/half watt resistor. I'm looking at the schematic of a Shure M68 and that's what they did. (For those who don't know, a Sure M68 is a AC powered mic mixer in a metal box with a RCA jack output. You could do a lot worse than copying Sure's design when it comes to solving RFI problems.)

[@russellhltn1396]

Went back and looked at Part 1. Not thrilled about the jack being close to the transformer. I'm concerned the magnetic fields of the power transformer could be creating hum between two different ground spots on the chassis. Still, signal ground connected to third pin power ground on two devices is just asking for trouble.

[@PsionicAudio]

Given that there are multiple chassis ground connections via all the terminal strips, floating the audio ground isn't really an option. I don't think it's transformer hum. But it's not a good design/layout. It has a famous brand name, but it's a deeply flawed thing. Makes me respect Kingsley even more.

[@buzzcrumhunger7114]

@@PsionicAudio have you gone and watched That Pedal Show's Simon Jarrett episodes? I haven't yet watched his actual channel videos, but the guy's a monster player, too! Which seems to greatly influence his designs.

[@dannbrauckmann1545]

@@PsionicAudio Yeah, I'm missing my Kingsley Maiden. I'm currently planning a build of a Matchless "HOT" Box clone. Hopefully I don't run into similar issues.

[@roncarter2188]

What brand of caps would you recommend for coupling capacitors? I'm going to restore and upgrade my two early 1970s Selmer Zodiac 50 and a Treble&Bass 50 amp heads. Thanks

[@Jonathan_Doe_]

NOS Mullard mustards if you really wanna pimp it out, otherwise Sozo Vintage or Vishay MKT1813.

[@zbaby82]

It sounds like a 1970s style distortion.

[@matthewf1979]

I’m starting to think tube pedals are a gimmick. It’s all your fault, Lyle!

[@cgavin1]

To be fair using tubes to create distortion is totally a waste of a transformer in this application.

[@sgt.grinch3299]

Hmmm, this pedal has an issue. I don’t play well with others either. I’m a Grinch you know!