TUT 6 - Dumble?

[Tubetastic]

While looking at the Kevin O'connor books on the LP site I noticed Vol 6 has a Chapter on Dumble. If anyone has purchased this Vol, any thoughts on it's content?

[txbluesboy]

I have TUT 6. I bought it because of the Dumble reference but was dissapointed. He just glazes over the high points and talks alot about the hype. You will learn a lot more searching the Dumble files here.
Terry

[John_P_WI]

I have had TUT 6 for almost a year and have not read it recently. IIRC, he does go fairly deep technically into local feedback loops, gain structure, frequency shaping and ways of making the design more flexible.

If you are looking for "only use this brand of cap / resistor and the magic is here" this is not for you. Kevin is great at teaching the fundamentals of the design.

I got stuck like a kid in the candy store in the "high gain" chapter later on...

John

[Tubetastic]

I can't disagree about a LOT of great info on here, Terry. It's where do you start!


Thanks too John. The problem for me with the KOC books is, they're not so readily available as others, and I like to get a feel of a book by viewing it.

Not having seen one, buying one makes me a little apprehensive as I hate ending up with another coffee table book -- I've sure bought a few Guitar ones, I must confess!


I thought a few more people on here may have succumbed to TUT6, if only for that particular chapter.

[David Root]

I have had TUT 1, 2, 3 and 5 for a while, and they're all very useful, certainly not coffee table books at all. The least interesting parts to me are the solid state chapters. I didn't buy 4 because it's all power scaling, not really all that interested, and I've not seen 6. Not been on his website in a while, will have to check it out.

I'm not a true Dumble or Trainwreck fanatic but I have learned more from this forum than any other by quite a margin.

[Structo]

I notice on his forum that he usually answers a question by referring to his books.....
So if you don't have $400 in books, you're out of luck.

[Tubetastic]

I have had TUT 1, 2, 3 and 5 for a while, and they're all very useful, certainly not coffee table books at all. The least interesting parts to me are the solid state chapters. I didn't buy 4 because it's all power scaling, not really all that interested, and I've not seen 6. Not been on his website in a while, will have to check it out.

I'm not a true Dumble or Trainwreck fanatic but I have learned more from this forum than any other by quite a margin.

I wouldn't like to suggest they're all Coffee Table books, David. Just buying one particular one (tut6) in my case, for one particular chapter that intrigues me.

[txbluesboy]

They are not coffe table books. There is a ton of great information in them, I have the whole set. TUT 6 however is not the one I would buy if I were to only get one. My favorite is TUT3, Its full of very useful examples. KOC did go into the local feedback loops in TUT6, however the text didn't seem to jive with the examples illustrated, and when I tried to do the math, the numbers I got were whack. Maybe its my simple mind but it just wasn't helpful to me. I bought tut 6 for the dumble info, but as I said before, I was disapointed.

[David Root]

Tubetastic, no criticism intended. I might feel the same as you about Vol. 6, but I've not seen it.

[Stanz]

I used vol 1 as a starting point for getting up to speed on tube amps. For that, it is a fantastic book. I still use it as a reference from time to time. Vol 3 also rocks with the many builds he has in there, from a champ to a Marshall Major.

One issue I do have is that if you look at the series as a whole, they are not cross referenced very well. It is written in a stream-of-consciousness sort of style, which does not work well for technical manuals. So if you want to figure out something about fixed bias, some part is in Vol 1, some is buried in a project in vol 3, and further refinement in vol 5, or was it vol 2. As Structo noted, if you ask Kevin a question, he assumes you have all of his books in your head and should know where to look. I do like his view point of challenging accepted norms and opens the possibilities of "what is possible". A fixed bias Champ? A single ended Vox with a 6L6 power tube? I would assume that aplies to Dumbles as well. It seems vol 6 is simply a need to move more merchandise, not that there is anything wrong with that. I felt he was throwing in a chapter about HAD to generate buzz. What could he add that hasn't been discussed here?

One comment I saw about a KOC design, "The Standard", which is his grail design, was that in the end the guy eliminated a bunch of the features because "I want to be able to operate the amp if I am drunk". I thought it summed up a lot about his approach, just because you can do something, doesn't mean you should. In the end though, I think he has contributed a lot toward better amp building based upon sound principles.

[Merlinb]

They are not coffe table books. There is a ton of great information in them, I have the whole set. TUT 6 however is not the one I would buy if I were to only get one. My favorite is TUT3, Its full of very useful examples. KOC did go into the local feedback loops in TUT6, however the text didn't seem to jive with the examples illustrated, and when I tried to do the math, the numbers I got were whack. Maybe its my simple mind but it just wasn't helpful to me. I bought tut 6 for the dumble info, but as I said before, I was disapointed.

I recently read TUT6 too, and I agree with you. His books contain a lot of mathematical errors. Sometimes his explanations of an amp circuit's operation or tone don't make sense, because he hasn't done the maths properly., and that's true in the Dumble chapter too.

The chapter on Dumble is pretty brief, giving a description of the circuit and some suggested mods which, as someone else has pointed out, can get unecessarily complicated in the features they offer. Actually he seems to spend more of the chapter talking about London Power, Fender and Marshall circuits, and amps in general, than about Dumble!

[Darkbluemurder]

I also bought TUT6 because of the Dumble and the Hi-Gain chapters. The Dumble chapter does not really contain anything new but it is not bad either. I like the Hi-Gain chapter more. But it seems to me that the book was not proof-read as well as the previous releases of TUT. Many of the schematics in the Hi-Gain chapter are incorrect (e.g. the Carvin Legacy, Marshall SL-X), and sometimes the text does not correspond with the schematic (e.g. Marshall SL-X).

Still, if you compare his books to others you will not find many that compare favourably.

[tubeswell]

The chapter on Dumble is pretty brief, giving a description of the circuit and some suggested mods which, as someone else has pointed out, can get unecessarily complicated in the features they offer. Actually he seems to spend more of the chapter talking about London Power, Fender and Marshall circuits, and amps in general, than about Dumble!

Hi Merlin

When are you going to write a book based on your site?

[Tubetastic]

Well, I decided not to get TUT6 - as much as it peaked my Interest. I just ordered TUT 1 & 3. For me, TUT 6 is for another day.


Thanks for the Input.

[txbluesboy]

You will get a lot from those two. Terry