New SE With Triode Mode KT120/150

[Cressy Snr]

Are you sure that decoupling cap on the driver stage needs to be as big as 470uF ? I reckon you could get away with eg. 47uF !

From my post above yours...

470uF cap decoupling the input from the driver should be 47uF, but I really cannot be arsed to change it....

....6SL7s should be 6SN7 on the heater diagram, but again I can’t be arsed to change them.

The actual cap in the amp is 47uF.

[IslandPink]

Oh Steve ...you took the bait !

[Nick]

Oh Steve ...you took the bait !

Perfect example of the danger of documentation. If you document something people assume its correct. If you don't you are safe to be certain you don’t know.

[Cressy Snr]

Oh Steve ...you took the bait !

Perfect example of the danger of documentation. If you document something people assume its correct. If you don't you are safe to be certain you don’t know.

You know Nick,
I’ve slept on what you said and TBH, I think you’re right. Apart from the fact that if you are going to post a schematic, you damn’ well make sure it is right, let’s face it, what I’m doing is not that interesting, if one is really going to be honest about it. I mean this is not 2005 is it? Things have moved on and I haven’t.

I appreciate, or should I say I’ve recently come to realise how difficult it will be, for anyone but myself to work up enthusiasm for yet another single-ended amp. Triode, pentode or whatever: if it doesn’t move on the understanding of such things, who gives a shite? Really.

Funny what this lockdown has done. I’ve become very interested in short stories, and writing about people and their fictitious 1960s experiences. I have around 30,000 words worth of stuff at the moment. Double that and maybe there’s a decent collection in the offing.

I’ll put up the corrected schematics later.

PS
Anyone wanting a story sample from my collection, for their missus to read, drop me a PM, with your email address.
It’d be nice to get some independent feedback.

[izzy wizzy]

Sometimes it's not about it being interesting for others (although it is) but build threads are fun IMO. Plus it's a way of documenting your progress from a personal point of view.

I know my GM70 amp is now on "small steps" but I re-read my own thread to see where I've been. Pretty sure I repeat myself. My website is only a place for me to stick stuff rather than on pieces of paper here and there that I'll lose. Here I can expand on that and hey, if someone else is interested; bonus. Plus peer feedback now and then is very helpful and appreciated.

Risk? This lot might take the piss now and then

[Cressy Snr]

Yep, build threads can be fun. But sticking too much of one’s own gushing about how it all sounds, has been the mistake I’ve made over the years. It can make you look arrogant and narcissistic, especially when it is in written form.

If you built the thing, you have the right to comment on negatives and what you plan to do, in order to improve the next outcome, and be objective about the positives, rather like Mark does in his long running speaker thread. This maintains credibility in the design process and in the person doing that design and evaluation. Also it maintains outside interest in what is going on.

What you don’t have any need to do is just keep saying that what you’ve done and the sound you are now making, is the best you’ve ever heard, time after time after interminable time. Sometimes a soupçon of er...objectivity as above is needed?

My God! My systems have made so many massive leaps forward, that what I had in 2005, must surely be from the acoustic era, except it isn’t. This isn’t a bloody hi-fi magazine. Can’t have a balanced view about your project? Then shut up until you can.

This long running uncritical attitude to the evaluation of a sound system, has unfortunately devalued the worth of any actual, real progress made over the years. A particularly plain speaking member of this forum, did try to warn me about this a few years ago now. Still not listening unfortunately. Don’t know what it’ll take. Maybe Nick could restrict my posting rights in the ‘Everyones Projects’ and ‘Loudspeakers’ forums, if this behaviour doesn’t improve. Nah! he’s not gonna do that. I’m ultimately responsible for what I write and need to exercise said responsibility with a teensy bit more thought.
The short stories are a far better outlet for fantasising, and could even make a few bob. You never know.

[Nick]

It can make you look arrogant and narcissistic

No, it just makes you look enthusiastic, which is always a good thing.

My point was really a internal dig at coding standards that requires documentation when IMHO the code should 90% of the time be its own documentation. My relevant point was just show the circuit, or the bits you find interesting. The chances of someone wanting to duplicate it without contacting you is small, and by detailing it down to exact component value just makes more work when you want to change it. It becomes a drag on your innovation. As well as making a change and listening to it (which is the good bit) you then have to update all the history (which isn't).

[pre65]

For me Steve, I'd be happy for you to keep your posting style.

I like the type of threads that go into minute detail of how things are made.

[Ali Tait]

Likewise. Don’t stop doing what you do Steve.

[Ray P]

Here, here...

Steve, there is a lot around that is sterile and formulaic, you always come across as human, with all that entails, and I wouldn't want you to change one jot!

[IslandPink]

& those schematics are really nice. I look at them when you put them up and think "I wish I could do nice neat schematics like Steve does".
With the ones I draw out, I do get exactly the same problem though - in that, no sooner have you scanned it and posted it up, you realise there's a mistake - or two or three !

[ed]

Steve I think you’ve adequately illustrated your awareness of your posting method, all the positive and all the negative aspects. You are the managing editor of your posting content and the readership has voiced it’s opinion on the results... for myself I can only hope you carry on.

I was going to draw parallels between your perception of your posting and my perception of my website, but I’ve scratched it. Suffice to say while my website belongs to a different era and has become completely self serving, your posting is still of value and is still relevant. My website is soon to cease, or change drastically..lets hope it’s not the fate of your postings.

[karatestu]

Yeah, carry on being you Steve. I enjoy reading your threads and it has never crossed my mind to judge you.

I am guilty of gushing over a modification and later have to backtrack. It does annoy me and I try not to do it but always fall back into it. It is an exciting hobby and it is difficult not to let the enthusiasm spill over on to the Internet.

[Cressy Snr]

I think the problem I have suffered from with describing my sound system over the years, is that whilst music is an art, audio design is a science.
OK, yes I accept that you design and build the stuff, in order to play recorded music, but hi-fi equipment is just that: equipment, designed using electrical and/or acoustical engineering principles.
I sometimes think that the way magazines described gear in the 50s and 60s was a lot more true to the spirit of the underlying science than it is these days.

Yes there was a lot of measurement and pictures of oscilloscope traces, and the sound quality was a paragraph at the end but to me it was being more 'honest' about the subject than some of the half-baked nonsense we read everywhere today; including the stuff I've put out.

It is difficult to describe the sound of a system in terms of music. Although I espoused that 'listen to the music' view for a long time, I've realised that it's nigh on impossible to do it effectively and come out with anything rational and coherent.

To say that 'turntable/tonearm/cartridge/amplifier or speaker X got me closer to the music' than component Y did is just meaningless. I mean, how the hell does that help anyone? To say that a component you built, allowed you to hear in forensic detail, the sound of fingers on strings, is equally meaningless because how do you know that forensic finger-on-string detail was what the producer wanted? It might be the the component has a raised treble response and you can't measure it because you don't have the test gear to do so.

It's easier to talk about bass, treble, midrange, detail, and dynamics, but again what are you supposed to reference that to as the solitary figure, designing and developing your equipment in your ill-lit garret. Bake-offs and places like Owston can allow you to hear what others are up to and the sounds they're getting, and they are valuable, because as a DIY'er they are often the only external references you have.

Which brings me to the gush factor I've too often been guilty of. Keeping the superlatives in check whilst not losing the enthusiasm, is going to have to be a major target: for my own rationality.

So to be objective about the latest mods to the 807 amp, and those to the speakers, all I'm going to say is that the works carried out this week, allow a closer approach to neutrality of presentation and a more realistic tonal quality to a wider range of instruments and voice types. This in turn allows a wider spectrum of musical programme to be enjoyed than was previously the case.

OK its a bit 1950s/60s but personally I think that it gives a bit more useful information than 'WOW it's fantastic! Best sound I've had from any system I've owned. I've had some decent sound in my time, but jeez, this knocks all that into a cocked hat. The transparency has to be heard to be believed, and this is just using bell wire to connect the speakers.'

[Nick]

It is difficult to describe the sound of a system in terms of music. Although I espoused that view for a long time, I've realised that it's nigh on impossible.

Yep, that’s why I could never understand the "Richard Dunn, its about the music" method of describing something. I could never get any information from the text. The cynic in me thinks that was his intention.