John Curl's Blowtorch preamplifier part II

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Hi Chris,
For a demonstration, I fired a single shot from a 32 ACP indoors and in the dark (special circumstances).

After that one shot, I was blind and couldn't hear anything. So forget follow-up shots in the dark! Anything you would fire after that is a blind shot. You'd probably do better squeezing your eyes closed and blasting away afterwards, but your rounds are very likely to strike something or someone you don't want to shoot. That was a .32 ACP, I can't imagine what it would be like with a 9mm or .45 ACP. Blind and deaf longer I would imagine. Not a good plan at all.

So to sum it up, fire a shot in the gloom and you will be completely helpless.

-Chris


In the USA and State dependent, $200 for a tax stamp and a 1 year wait will prevent the hearing issues.

The additional cost will depend on the caliber and how much suppression you want.
 
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None whatsoever!

Fired a Ruger mini 14 as well. Interesting rifle, quick. Recoil wasn't too bad at all. But I was a lot younger then.

I have never fired an M14-of any flavour.

-Chris

Edit:
Can you imagine yanking out your .32 ACP with a suppressor hanging off the end? It's a funny mental image. It might go better with my Sig-Sauer P220 in .45 ACP. Still, I'd much rather punch paper with ear defenders on. That's another test for me. My wife says I can't shoot anymore. Not what I want to hear. The Sig is the nicest handgun I have. It is accurate.
 
Direct blowback is not a good choice for suppression. For instance suppressing a Walther PP in 9mm Kurtz (007) is not a good choice as the direct blowback causes a lot of garbage and noise to be blown out the breach, and ends up not suppressing as well as a delayed blowback.

.22rf is probably a good exception. .22rf suppresses very well in most firearms.
 
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"Silencers" were included in the American NFA of 1933 in the same category as sawn-off shotguns and automatic rifles. Supposedly to reduce game poaching (!) the classification seems unfixable after all these decades for political reasons. If our hearing suffers, tough t.

All good fortune,
Chris

NFA 1938.

Barrels for any shoulder fired firearm less than 16".

Shoulder stocks for pistols.

Any fully automatic firearm (pistol or rifle).

Destructive devices (rifles greater than 50cal except Black Powder)

40 states now allow suppressor possession by individuals.
 
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A very reasonable comment, having worked with the designers of both the AD1896 and the ESS DAC for years I can say the opinions on what people hear runs a larger gamut than you might think.
Actually a big part of it is where peoples creative vs logical predisposition lies. IME very creative people tend to hear, or think they hear larger differences and those differences are often tied to emotional responses. Logical types tend to just hear in a more simplistic fashion. Brighter / Duller / deeper / less width etc etc. I have had less luck getting consistent results from creative type customers. They should be just making the music LoL!
Why do we continue to have mainly folks sitting in their ivory towers doing sighted listening and pontificating on what they hear as irrefutable fact. I've given up on "mistaken beliefs about some of the underlying mechanisms" with folks that should really know better.
There are two issues here a/ the sighted listening and if they are in fact hearing 'something' b/ Some possible explanation for that 'something'.

A good example, since we are talking about ESS DAC's is the 100MHz clock and it's influence.
I have a friend who started implementing SAW resonators for the master clock instead of quarts oscillators. The overwhelming consensus was they sound different and all of his customers felt better. I don't have too many issues with that. Clocks have an impact on DACs sound and a good set of ears will pick them in a double blind test.
Getting on to the second part of your statement, the 'underlying mechanisms' bit was interesting. There were heroic efforts in building ULN at low freq power supplies for the SAW clock. Theory was very low freq jitter was they key.
I compared phase noise plots of all the clocks and clearly SAW resonators are not very good at close to carrier noise. In fact they are pretty poor.
I theorized that SAW clocks were in fact adding some euphonic artifact that sounds good but no one ever bought that explanation.

Oh well - people will believe what they believe. :)

T
 
Unfortunately, the Mini-14 accuracy was never as good as the AR15/M16. It is a fun rifle, but I'll take the accuracy of the AR15 any day.

This is a misunderstood thing. There are Mini-14's that are as accurate as any AR15 (stock). And there are some that can't hit the broad side of a barn. You only know if you shoot it... Why? I don't know, it has always just been luck of the draw for some reason.
 
Actually a big part of it is where peoples creative vs logical predisposition lies. IME very creative people tend to hear, or think they hear larger differences and those differences are often tied to emotional responses. Logical types tend to just hear in a more simplistic fashion. Brighter / Duller / deeper / less width etc etc. I have had less luck getting consistent results from creative type customers. They should be just making the music LoL!

I can relate. I was asked to look in on the system owned by one of Australia's most renowned classical musicians. He world famous and highly respected. I walked into his listening room (filled, I might add with very average mid-end equipment), listened to 10 seconds of music and immediately switched it off and got about to rectifying the very obvious problem of one speaker wired out of phase. Once fixed, I insisted he sit down and listen.

Then it got disturbing. He heard no difference! Yikes! This is a guy who spends his life in front of orchestras, as a conductor and the imaging of his hi fi system was unimportant to him.
 
Very kind of you to provide justification for JC's post, which he either could not or did not want to.
I wish I had a groupie like that! ;-)

Jan

Oh, it seems that you´ve now extended your feeling of animosity to another member.....

-) As said before, it is usually common knowledge that a system with higher bandwidth has faster rise time too. Do we agree on that?

-) we all (including you and me) were present in the pasttime when the bandwidth on analog vinyl playback system were discussed, and we discussed back then, that up to 70 kHz were found on available vinyl records (for example Sheffield drum record direct to disc, cymbal crash, wasn´t it Nelson Pass examining it?)

Therefore my surprise that you cited this sentence from John Curl:
"Still, even with added resonance, the rise-time is usually faster with analog playback than with CD."

and commented with "Nope. Plain BS" .

Therefore my question, as your comment contradicted common knowledge.

As a remark, to discuss with "janneman" in those days was always a pleasure, while todays degree of animosity/hostility imo isn´t helpful, so i clearly miss that incarnation.

Complete BS.
Specially to satisfy Jakob2 and Tournesol: I have published blind tests that show that people liked vinyl when they THOUGHT they were listening to vinyl, even when it was actually digital. The same test showed that people didn't like what they THOUGHT was digital, even when in reality they were listening to vinyl.

Jan

First of all:
Why should that satisfy "Jakob2"? I cited the statement that you attacked and there wasn´t any kind of audibility included.

This "BS game" is horrible because it misses nearly everything a discussion forum should be about.

You have of course reason to attack John Curl´s statement that something was "proven" with listening tests, but to think that you could "disprove" it by results of other listening tests is misleading too.
 
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Regarding 70kHz signals on vinyl, given literature I have seen shows that cutting heads really start to suffer above 18kHz, even with half speed mastering you will have trouble putting any sort of significant level above 40kHz in to start with and you won't be able to add enough boost to cut it at high level, even if you could play it back.

Which suggests that, although there may be HF information that bats and dogs can hear, the level will be so low that normal rise time definitions (10-90%) won't hold and CD, being able to slew rail to rail in one sample actually does a better job of it?
 
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Oh and the plot thickens with the Telarc 1812. I've ordered a CD, but based on the DR database the CD was cut with 6dB higher RMS levels, so the cannons were compressed (or the vinyl rip is wrong). Interesting.

As for why this matters. 6dB is a lot when you are the poor sub trying to pump out that 38Hz. JBL M2 owners don't need to worry but in theory if you are playing the vinyl at a loud but apparantly acceptable 85dB for the orchestral part your thuds will be at 111dBa.

On the CD it's easier, but I can't think those flat tops at FS will do the tweeters much good :)
 
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There is significant HF content. They are big clips
 

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What do you like?

Tricky... Lots of things, not usually everything from any given artist though. eg,
Floyd, Martyn Bennett, Zappa, Joe Bonamassa, London Grammar, Roy Harper, Yes, Steve Wilson, Tangerine Dream, Thomas Tallis, Nigel Stanford, Baba Naga, Led Zep, Moody Blues, Michael Kiwanuka, Ozric Tentacles, Camel..... Well, those are from recent history of my player.....
 
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