John Curl's Blowtorch preamplifier part II

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Is there any meaning to this or is it just bragging into space?
Basically just talking to dvv, who mentioned his thoughts on the issue. Everything is always a balance, the PC speakers are using a ridiculously small EI unit, as one would expect - it's only bcarso's engineering that enables the amps to do as well as they do, subjectively.


P.S. The signature you're using was addressed to me. SY's brilliantly twisted humour IIRC.
Which is also why I asked about your first name BTW.
Sorry, I'm not quite following you here ...
 

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AJT,
I can eat a large popcorn at the movies all by myself, does that make me a great movie critic! ;)

When we all start using a 65 cent 3" PC speaker as a reference for audio quality we can all give it up I must think. :crazy:

Thats because you have no imagination .... :)

I was interested in the plane of the top of cart body, not the angles set by the protractor (I have a vintage Dennesen).

Scotty since VTA is also affected by VTF , this angle is usually dialled in after correcting vtf, get yourself a new test record , necessry at the very min and necessary for proper setup.


Or ...you can use on of those USB THING A MA JIG , and scope it out ..:)
 
AJT,
I can eat a large popcorn at the movies all by myself, does that make me a great movie critic! ;)

When we all start using a 65 cent 3" PC speaker as a reference for audio quality we can all give it up I must think. :crazy:


great critic? i doubt it....;)

a reference is something i use to compare another with, it doesn't have to be the best, only that i can put a finger and say, the other one is better....or worse........;)
 
When we all start using a 65 cent 3" PC speaker as a reference for audio quality we can all give it up I must think. :crazy:
Until people get over this "hangup", :p, the industry will always have a problem, methinks. What one has there is a quite decent midrange unit, which loses only on the top and bottom, it's actually covering, say, 95% of the sound that counts - and it's how well that is reproduced, for all the reasons I've mentioned many times, that's important.

Some people may recall I visited another member some weeks ago - he's using a pair of identical Scan-Speak drivers, on each side, to cover about the same range, driven by an amp devoted those duties - and I didn't fall off my chair, and think, Wow, that is so superior!! The totality is what counts, it succeeds or fails on the basis of what reaches the ears ...
 
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diyAudio Senior Member
Joined 2002
Hi,

I don't recall writing that and it doesn't read as something I would write. Maybe I did and forgot, but a forum search didn't turn it up.

It was many years ago, Stuart.

It doesn't really matter. It was quite catchy and kind of funny at the same time.
I always complain about the lost art of recording, don't I?

Frank, can you please refresh my memory - what speakers are they driving?

Speakers are SD Acoustics SD1, 92dB/1W/8 Ohm nominal.

You are who I suspect you are? Dimitri Da....?

Ciao, ;)
 
What I've realised is that getting the "right" 95% of the sound right is the heart of the matter - if you do that, the main killer of having sound work its magic is defeated. Then you can scale up in quality of the parts, and power delivered and handled cleanly, as far as you want to go, and a good chunk of the other 5% gets on board - icing on the cake. But if the heart of the sound is fragile, is intrinsically flawed, then it will always ultimately disappoint. The quite dreadful quality of many very expensive systems tells you that immediately ...
 
How about Fast Frank for you?

Frank you would have to look inside those pc speaker and see that I wasn't being joking about the use of a 65 cent speaker. There is no technology in those inexpensive JBL pc speakers, paper cone, smallest magnet that will work and a stamped frame made by the millions to go into every cheap tv or anything else they can fit into. The measured distortion would be way off the charts for being able to make comments as you do. It just makes your comments silly.

I'm sure that Brad did all he could to use the simple chip amp in that application but he must have been under extreme budget constraints on what they would let him do. You might as well be talking about a 9-transistor radio as far as I am concerned.
 
Frank you would have to look inside those pc speaker and see that I wasn't being joking about the use of a 65 cent speaker. There is no technology in those inexpensive JBL pc speakers, paper cone, smallest magnet that will work and a stamped frame made by the millions to go into every cheap tv or anything else they can fit into. The measured distortion would be way off the charts for being able to make comments as you do. It just makes your comments silly.

I'm sure that Brad did all he could to use the simple chip amp in that application but he must have been under extreme budget constraints on what they would let him do. You might as well be talking about a 9-transistor radio as far as I am concerned.
Them's fightin' words ... :D

Looks like I will have to do a serious effort at recording what the PC sounds like, the organ piece I mentioned earlier has got some choice, gutsy passages with plenty of depth to them - should be able to capture a fair bit of the sense of that - and post it. You will then have the YouTube original to compare it with ...

Harman please, not JBL. I have fiddled with the drivers, the magnets are quite decent - and the distortion comes in because the amps crumble when strong energy draw is required. The range 100 up to about 200Hz is quite poor for harmonics but everywhere else is pretty sound, I've run frequency sweeps through them many times and the sound is relatively clean.
 
Already have a problem - running it at half volume, my wife at the other end of the house says it's too loud, she can't keep focus on what's she's doing, :D ...

Edit: The nice thing about organ works is the tremendous sense of space that's captured, even in the softest, most melodic moments there is a great feeling of expansiveness in front of one.
 
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