Hot Tubes Build Troubleshoot - New GM Layout

[Bernardduur]

Can't measure mine as my DMM has no capitance reader

No Ruud Bernard here..... dunno who he is btw

I used to love the unit; now the extreme bassiness really bugs me

[gaussmarkov]

hmm.  i don't know if we can read the capacitance indirectly like that.  certainly a capacitor in parallel with a resistor has an impedance with some reactance and some resistance.  does your DMM read general impedance, or just capacitance?  and then, i think i read R.G. caution that one cannot generally read component values in a circuit the way we would like.  i guess i just don't know enough about it.

[gaussmarkov]

No Ruud Bernard here..... dunno who he is btw

me neither.    i just recall that Ruud is a given name in the Netherlands.

[SonicVI]

hmm.  i don't know if we can read the capacitance indirectly like that.  certainly a capacitor in parallel with a resistor has an impedance with some reactance and some resistance.  does your DMM read general impedance, or just capacitance?  and then, i think i read R.G. caution that one cannot generally read component values in a circuit the way we would like.  i guess i just don't know enough about it.

It reads capacitance, just some holes that you stick the component in. I didn't expect it to be much use to measure it in the circuit.

Ok, I just googled N3300 and apparently this has to do with the type of dialectric and is not the value. I'll have to desolder it and measure.

[SonicVI]

Ok, it reads 039 on the 200pF scale so I'm assuming that's 39pF.   I've just been full of incorrect info haven't I?   

 

[electrobuster]

I just tried a 39pf in parallel with the 150k resistor, R11 on the Gaussmarkov layout and the bite is back. When I tried the 2.2nf on the 1.8m and then on the 150k the gating disappeared but the sound lost it's edge if that makes sense. The only point of reference I have for the Hot Tubes is Kim Gordon from Sonic Youth, I think Bernardduur mentions somewhere that Kim is known to use one for a bass distortion. With the 39p in there I can now get that sound, check out the song Kool Thing from "Goo" . It's better on guitar now too. So unless anyone finds any different information I think thats it. Good work chaps

S

[gaussmarkov]

I just tried a 39pf in parallel with the 150k resistor, R11 on the Gaussmarkov layout and the bite is back. When I tried the 2.2nf on the 1.8m and then on the 150k the gating disappeared but the sound lost it's edge if that makes sense. The only point of reference I have for the Hot Tubes is Kim Gordon from Sonic Youth, I think Bernardduur mentions somewhere that Kim is known to use one for a bass distortion. With the 39p in there I can now get that sound, check out the song Kool Thing from "Goo" . It's better on guitar now too. So unless anyone finds any different information I think thats it. Good work chaps

S

i agree.  that sounds like a wrap.  sonic,  thanks so much for pulling that cap off and measuring it.  you are a hero.   

39pF makes a lot more sense that 3.3pF.  now we are in the  ballpark of the cap values in simiilar circuits.  and electrobuster has confirmed with another actual build.  dude, you rule too.

sweet!  isn't it curious that this circuit has been around for so long, the schem sitting on jack's site, and we couldn't find this info somewhare else?  go figure. 

now i will really change the project file on gaussmarkov.net.  cheers all! gm

[km-r]

never heard a hot tubes before... maybe you guys could upload some clips?

[gaussmarkov]

   ok.  new project files up:  http://gaussmarkov.net/wordpress/circuits/hot-tubes-clone/

again, thanks to everyone, including electrictabs for kicking the whole thread off.   

[SonicVI]

never heard a hot tubes before... maybe you guys could upload some clips?

Go to the Snarling Dogs website and listen to the clips of the Black Dog or Tweed E Dog or Blue Doo if they still have them on the site. They are copies of the Hot Tubes with very minor changes.  I have a Hot Tubes and  Blue Doo and they do sound very similar.  I'll try to make a couple sometime soon.

[electrobuster]

.

  ok.  new project files up:  http://gaussmarkov.net/wordpress/circuits/hot-tubes-clone/

again, thanks to everyone, including electrictabs for kicking the whole thread off.   

No problem, glad to inspire more research. Maybe electrictabs should be my new tag, the buster thing is pretty lame and embarrassing.

[snap]

see here for electrictabs aka Dr. Boogey:
http://www.diystompboxes.com/smfforum/index.php?action=profile;u=1175   

[electrobuster]

Ah I see, maybe GM got us mixed up, which makes it even more embarrassing, that Tabs dood knows stuff. Hehehe

[Bernardduur]

Awesome man! I never expected it to read 39 pF; it was the main source of my bassiness as I replaced it some time ago with a 3n3 which will give it the bass! I quickly searched around and found the original cap and replaced it and now it sounds as sweet as it should

Anyone tried it in an FX loop yet?


Oh, as the Tweed Dog (of Snarling Dogs) is a Hot Tubes clone, what does the attack control do (switch to go from Snarl to Bite)?

[electrobuster]

Just tried it in an effects loop on an old solid state amp. Bernardduur is on the money with this one, It sounds awesome, much smoother and clearer. A great combination for a solid state amp with an effects loop.

[Bernardduur]

OK, I KNEW I wasn't dreaming..........

This is a new favorite for me now
I wonder if it is the same with other CMOS inverter based pedals like the Red Llama

[gaussmarkov]

see here for electrictabs aka Dr. Boogey:
http://www.diystompboxes.com/smfforum/index.php?action=profile;u=1175   

naw, i mixed up mydementia and electrictabs.    i was actually going to go back and check who started the thread, and then something distracted me.  it was late ... it was lame ... what can i say?     apologies to mydementia.

i also forgot to mention that there has been another hot tubes schem kicking around for ages, created by Mark Hammer and R.G. and called the MXR Hot Tubes.  Mark has been trying to correct the misattribution to MXR for years.    as i recall, they deliberately removed the tone section.  and, yep, there is a small cap across the first inverter.  their component values differ a bit, probably they were looking at an older EH Hot Tubes.  you can see the R.G. schem all over the place, including "Guitar Related Circuits" here:  http://www.montagar.com/~patj/mxrhott.gif.

only problem is ... they also have another feedback cap on the second inverter in the signal path.    and there's one extra inverter, too.    so as with so many of these boxes, there were several versions.

perhaps we should name this one?  inadvertantly, R.G. already named his the "MXR" hot tubes.    what shall we call this one?

[gaussmarkov]

Awesome man! I never expected it to read 39 pF; it was the main source of my bassiness as I replaced it some time ago with a 3n3 which will give it the bass! I quickly searched around and found the original cap and replaced it and now it sounds as sweet as it should

now that is excellent news!  stobiepole is going to check his build, too.  yesterday, he told me that he found the same thing as you with a 3n3.  so it still looks like we are all on the same page.

cheers, gm

[gaussmarkov]

oops.  i misread the MXR HT schem.  same number of inverters, 3, in the signal path not including the tone section.  and only one bypass cap on the first inverter.  i keep seeing that op amp as an inverter.    so actually, all we needed to do was look at R.G.'s early schem and reproduce that with the alternative component values. 

[Bernardduur]

oops.  i misread the MXR HT schem.  same number of inverters, 3, in the signal path not including the tone section.  and only one bypass cap on the first inverter.  i keep seeing that op amp as an inverter.    so actually, all we needed to do was look at R.G.'s early schem and reproduce that with the alternative component values. 

LOL

That was exactly as I though; "he, that's just the same hardwired in the tone bypass mode"

Someone has the schematic of the Tweed E dog? I read on this forum it was available a long time ago