TuT FX Loop Values

[chunkitup]

Could someone verify all the cap values in this loop. Dont worry about the power supply decoupling. But I just want to know which caps are nano values or micro values. The send coupling cap looks like a 6.8microfarad which seems big. Thanks

[tubeswell]

Here is the fx loop from TuT1. Could someone verify all the cap values in this loop. Dont worry about the power supply decoupling. But I just want to know which caps are nano values or micro values. The send coupling cap looks like a 6.8microfarad which seems big. Thanks

Yes going by the the way he scribbles his other 'U's, it definitely is 6.8uF I'd say.

I must say I've never read one of KoC's books before - those hand drawn schematics look messy don't they?

[Merlinb]

Yes going by the the way he scribbles his other 'U's, it definitely is 6.8uF I'd say.

I must say I've never read one of KoC's books before - those hand drawn schematics look messy don't they?

Yes it is 6.8 microF, and yes it is big considering how enormous that send pot is! Chances are that pot is going to be turned down at least to 10% of its resistance all the time, in which case you could use something between 220nF and 1uF without any trouble.

(Actually, all the caps in that schem could be reduced by a factor of 10 and you still wouldn't lose any bass)

[DIY_Guy]

I must say I've never read one of KoC's books before - those hand drawn schematics look messy don't they?

It takes some time to get used to. And I find it funny when he draws the same thing in a different volume, yet it will have different component values. Would have saved him time if he would have just copied and pasted.

[Joey Voltage]

Yes it is 6.8 microF, and yes it is big considering how enormous that send pot is! Chances are that pot is going to be turned down at least to 10% of its resistance all the time, in which case you could use something between 220nF and 1uF without any trouble.

(Actually, all the caps in that schem could be reduced by a factor of 10 and you still wouldn't lose any bass)

That loop is over engineered a little IMHO. Equally good performance could have been had if He trimmed the fat from that VE stage, a simple AC CF would have been just as good for the driver. Oh well.........

[JHow]

I must say I've never read one of KoC's books before - those hand drawn schematics look messy don't they?

For the money, I would expect more.

[Bruce / Mission Amps]

For the money, I would expect more.

I'd expect more too... a possible letter from his lawyer demanding satisfaction from a copyright infringement for copying and posting on the NET.
Unless someone has seen it posted by K. O'c, I be worried that stuff is proprietary and not public domain ... could there be trouble on the horizon?

[Merlinb]

That loop is over engineered a little IMHO.

Indeed. The word "best" maybe a little over-reaching.

could there be trouble on the horizon?

Man you worry too much! He doesn't go get a lawyer when commercial companies copy his power scaling circuits, so I doubt he'll care too much about a scan of one (admittedly well known and not particularly inspired) circuit from TUT1!

[JHow]

...He doesn't go get a lawyer when commercial companies copy his power scaling circuits, so I doubt he'll care too much about a scan of one (admittedly well known and not particularly inspired) circuit from TUT1!

The way US copyright law works, if you don't defend yourself, the courts eventually assume you have relinquished your rights. Defending yourself can be limited to a simple "cease and desist" letter, which is often sufficiently scary enough for material to be removed.

[chunkitup]

Loop Pic Back Up

Ok here it is again. If they want they can sue me for my rusted old pick up! Ha!

[imaradiostar]

I'm sure others can comment but I think you can build a better sounding and more flexible loop with about half the parts.

Put the send volume in front of the cathode follower (bias circuit is already perfect for it) couple the cathode to the output with a cap and a resistor to kill the voltage across it. On the return side just a volume into the input of a triode will do- no need to clutter things up. Depending on what you prefer the volume could be after the triode. I supposed you could keep the whole blend thing but if you're using it with pedals you probably won't want that anyway.

I've taken to using a mosfet for the send side of things so I can save an extra triode for places where gain matters. On some of my amps I use a mosfet to send and a 6GH8A on the return/phase inverter side. The triode in the 6GH8A is the split load PI and the pentode has enough gain to drive the triode to sufficient volume. It makes for a nice simple amp with a loop!

jamie

[Bruce / Mission Amps]

Ok here it is again. If they want they can sue me for my rusted old pick up! Ha!

See, that's the kind of attitude that gets people pissed off.
Kevin is a pretty cool guy. I would have at least asked him first... he used to post here frequently and has been supporting the DIY crowd for years in some way or another.
I'd show a little respect... that's all I'm saying.

[Joey Voltage]

Man you worry too much! He doesn't go get a lawyer when commercial companies copy his power scaling circuits, so I doubt he'll care too much about a scan of one (admittedly well known and not particularly inspired) circuit from TUT1!

Yeah, this much clearer "slightly" modded version of it has been publicly available since like 2002:
http://www.mif.pg.gda.pl/homepages/t...s/FX_Loop4.gif

seems to have an out the fire escape accountability for anything he misrepresents as well, I don't know if you remember that whole silly mu-amp thing between Hynes and I about a year ago but I have a humorous addition to it.

[Merlinb]

I don't know if you remember that whole silly mu-amp thing between Hynes and I about a year ago but I have a humorous addition to it.

What thing was that? Sounds like a fun read!

I have seen examples of ideas in the TUT books that KoC has himself stolen from other sources without reference, so he's not blameless himself.

[madkatb]

I agree with Bruce. My wife bought me the whole series, one at a time, as Christmas presents. She would phone, Kevin would answer and she'd order the next one in line. I've had opportunity to talk to Kevin a couple of times myself. His whole line of books, not just the TuT ones, are aimed at diy. I don't know that I would have dared tackle any electronics projects without the knowledge I gained from his books.
Are they expensive? yeah.
Are they well written? yeah.
Do they contain mistakes? yeah
Is there another way of doing the same thing? yeah (welcome to the world of electronics)
but if you read them you'll be better for it. And if you have questions give Kevin a call, he's always taken time to answer mine (and refer me to the right page).