Merlin B's new book on tube amp power supplies

[Super_Reverb]

Can anyone give me some info on Merlin's new book on P/S for tube amp? Looking for content, analysis vs. examples, your impressions etc.

Have read his book on preamps and thought it was very good, informative, AND practical. Especially liked the comments on circuit design effects on tone - plate load resistor vs. harmonic generation, grid current vs. tube cutoff distortion effects, etc.

thanks,

rob

[David Root]

It is rather more theoretical than the preamp book. It doesn't have a lot of examples and optional ways of doing things, but you will certainly fully understand what is involved in good power supply design.

That was my first impression. I will be fair and give it another reading but it could have used more specific examples I think.

[mumford]

I'd agree with David. It's a different kind of book than the preamp book, less of a design guide than an explanation of how the components work. The design stuff is still in there, but not as much of it.

[tubeswell]

Yes I find it useful, however there are some unanswered questions I have still, for example, about designing filter systems such as whole-of-supply CLC filters where one needs to work out total HT current draw for the whole amp in particular including the component parts such as SE or PP output stages. (I guess that might come forth in a subsequent book?) In reality I guess the art and science of amp design is about a continuum between all the different parts of the amp, and I suppose one has to draw the line if one is trying to compartmentalise the requirements of different components, like pre-amp, and power supply etc.

Don't get me wrong - I really appreciate and am very grateful for the books and the website, and Merlin is much more knowledgeable than some amateur hobbyist like me.

[cyclone_cj]

I think it is an excellent design reference if you actually want to design something different than the standard series resistance power supplies. You can just copy an existing Fender or Marshall PS and be good to go there. There is quite a lot of discussion about series and shunt regulation, lots of good stuff about heater supplies and noise reduction methods. Pro's and cons of different "tricks" like elevating the heater supply and DC filament supplies. Excellent section on bias supplies with lots of examples. It's more theory heavy with fewer fully developed circuits than his preamp book, but there is SO much information there, specific to musical instrument amps. All the math is there so it's easy to implement. It's definitely worth owning, esp. if you are designing from scratch rather than rearranging sections of existing amp designs or building clones.

[David Root]

I have since re-read it during a 5 hour plane ride, and I think I was a bit hard on it earlier. The section on using transistors & diodes to replace a choke was very illuminating, and would be a very useful alternative in cramped space. There are also more examples than I remember the first time I read it.

Also the bias and heater supply chapters are both very good.

One thing that was not there is line regulation ahead of the amplifier, which I was hoping would be included, was referred to but not discussed. To be fair, the book's title is Designing Power Supplies..., not Designing Line Regulation..., so I can't legitimately complain about that.

Looking forward to the third volume, Designing Push-Pull Tube Power Amplifiers!

[Cliff Schecht]

Yeah to be fair to Merlin, you could easily fill a book just on various line regulation methods.

[Structo]

I have both his books and enjoy reading them.

[surfsup]

I am a noob and find them very informative and worth the money. In one place you get a ton of info, as opposed to scouring the internet and reading 1000x the text to get info that is relevant. Im doing both, but merlin clears up some stuff though there isnt much basic info on circuits, EE, component stuff. Some things are assumed the reader knows. I get confused, for sure, but each time i read, it makes more sense.

I do wish more info was thete on grounding and the "whys" of using this or that, but again, thats sort of part of the assumptions.

[David Root]

"Each time I read it, it makes more sense" That's how I learned, originally by reading and re-reading the TUT books, which when I started in on them I wondered if I would ever get on top of it.

It will happen, the other necessary side of this coin is to build, build, build!!

[xtian]

I just got Merlin's two books. Where is the third, on designing tube power amplifiers?!?

[Structo]

That is the one I am waiting for.

[TooL46_2]

Also waiting for the power stage book. Got this one for now

http://www.amazon.com/Vacuum-Tube-Circu ... 0976982242

[xtian]

Also waiting for the power stage book. Got this one for now

http://www.amazon.com/Vacuum-Tube-Circu ... 0976982242

$60 = ouch. Please just tell me the best bits.

[Colossal]

$60 = ouch. Please just tell me the best bits.

I have all three of Kuehnel's books and while they are not cheap nor reading for when you are sleepy, they are great resources. Basically a thorough discussion of every facet of design with interesting historical elements. Kuehnel takes pure theory and puts it into context of guitar amps and specifically speaks to that application because of the non-linear aspects we (as distortion whores) want.

I feel the books could have been much more rich and you basically get one worked example per concept but still, very valuable. There is a complete design example in the power amp book which takes you from beginning to end. I think this could have been expanded upon much more greatly for the reader's benefit. The charts and graphics leave a lot to be desired in terms of their presentation quality but do get the point across. The great thing about these books is that all of the necessary equations are spelled out so if you are good with Excel, you can replicate everything and apply it to your own builds.

Despite some of the shortcomings, they are great books and I highly recommend them if you are serious about really understanding design. It is all math so some people might glaze over and be put off by that. But the simple fact is that to understand amps, some math is required and you either embrace it and dive in, or you don't. The section on tone stacks and frequency plots is very good.

My books are literally falling apart as I've read through them numerous times and still refer to them not infrequently. I consider them a valuable addition to the bookshelf. I like this sort of book, I don't want some watered down version that leaves me wanting some of my money back. I can find any of those resources on the internet but individual mileage will certainly vary. These are NOT books for someone looking to solder by numbers or mod a Valve Junior. They assume some knowledge of electronics.

Hope that helps!