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Old 23rd Nov 2023, 8:18 pm   #3441
ajgriff
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Default Re: The Audiophoolery Thread.

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Originally Posted by Beobloke View Post
Cable lifters have no place in this thread as there is sound science behind them and it's all about keeping cables away from the "noise floor". Allow me to explain...etc
Brilliant and such eloquent drivel. Nordost would pay highly for your services.

Alan
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Old 23rd Nov 2023, 8:22 pm   #3442
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Default Re: The Audiophoolery Thread.

A witty bloke beo.
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Old 23rd Nov 2023, 11:01 pm   #3443
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Default Re: The Audiophoolery Thread.

Some lateral thinking....

The power cables for your active lifters would need lifters of your own, as you said.

But these would also need their own power cables and lifters.

And so on, ad inf.

Now, instead of vanishing up your own tuned port, mount the second lot of lifters upside down! connected to the same power cables they are lifting by pushing away from the floor.

Perfecto!

And a horrible inifinite recursion is avoided, though you miss out on the profit of selling an infinite number of lifters per system.

David
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Old 24th Nov 2023, 12:01 am   #3444
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Default Re: The Audiophoolery Thread.

Instead of using lifters from the floor, you need hangers from the ceiling. Such a length of hanger could easily be made temperature compensated.

Almost reminds me of a joke pulled by a student at Southampton (who became a full Professor and is now retired). He wrote on headed notepaper from RAL that there was a risk of small scale thermonuclear detonations at the focus of high intensity laser beams. It caused more reaction than he had expected with the near closedown of the laser labs.

His letter said that the risk could be mitigated by locating a temperature compensated boron rod in proximity to the focus; and he had arranged a rod of grey plastic with some wires attached, so when the safety officer arrived to tell him to shut off his laser he said "It's OK - I've got a temperature compensated boron rod just here".

At that point they knew they had been had!

Craig
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Old 24th Nov 2023, 2:55 am   #3445
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Default Re: The Audiophoolery Thread.

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We need more fact free subjective tripe on here!!!
Well, some of the stuff the same Chris Rogers came out with in support of design decisions on his Sirac-1 valve amplifier would do nicely...

I'm interested, please elucidate - tripe is tripe and being a northerner (albeit vegetarian) I love the stuff

Glad I only built the speakers! In fairness I was always happy with them.

Steve.
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Old 24th Nov 2023, 8:58 am   #3446
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Default Re: The Audiophoolery Thread.

It's a sort of Peter Belt thing - Rogers undoubtedly designed a decent speaker, but he veered off into rampant subjectivism - the denunciation of the the Quad 33 as "making the music sound amateur" (!) was in a review done on his watch. The particular phoolery around Sirac, which was a queer-looking beast using kinkless tetrodes - whether 88s or 66s I can't recall - was in his description of optimising the feedback networks by ear, balancing "harshness" against other audible artifacts. Even across a space of nearly fifty years, his description is phoolery of the first water. Curiously, the Sirac project flopped..
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Old 24th Nov 2023, 9:39 am   #3447
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Default Re: The Audiophoolery Thread.

The articles are here if you scroll down:

http://www.saturn-sound.com/history/...20projects.htm
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Old 24th Nov 2023, 10:31 am   #3448
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Default Re: The Audiophoolery Thread.

In the light of the experiments I saw on the Blaze channel the other day, audiophools should probably not be standing anywhere near their sound reproduction equipment, for fear of affecting the sound quality:

The subject held electrodes in both hands (each about the size of a red bull can) attached to a machine that detects static electricity. He was able to generate static (unremarkable) but seemed to be making it change polarity, or at least fluctuate, at will. Aha, I thought- he's differentially squeezing the electrodes, but then the experiment was repeated with his hands held NEAR the electrodes. No, he wasn't shuffling his feet on the carpet.
The same bloke was able to increase the number of photons his body was emitting by a factor of 100 under laboratory conditions. I didn't even know we emitted photons...

There's plenty to laugh at on the Blaze channel, but it's to be noted that you can fool some of the people all of the time, but you're unlikely to fool Nick Pope.

For true high fidelity experiences perhaps the enlightened should stand outside while the music is playing indoors, so that they can imagine what it sounds like without the distorting effect of human proximity.

Dave
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Old 24th Nov 2023, 10:36 am   #3449
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Default Re: The Audiophoolery Thread.

I've often wondered if having a turntable in my listening room makes the sound worse when listening to vinyl but I can never prove it as, when I take the turntable outside the room, I can't play any records.
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Old 24th Nov 2023, 10:52 am   #3450
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Default Re: The Audiophoolery Thread.

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I
The same bloke was able to increase the number of photons his body was emitting by a factor of 100 under laboratory conditions. I didn't even know we emitted photons...
Dave
The only photons you emit are infrared. By the Stefan-Botzmann Law (which used to be A-level physics back in the day) the emitted power is proportional to T^4, where T is in Kelvin. So a factor of 100 would imply his body temperature was reduced by a factor of 100^0.25 or 3.16. Now body temperature is 273+37 = 310K, so a reduction of a factor of 100 in emitted power implies his body temperature was reduced to 310/3.16 = 98K, or 21 degrees warmer than liquid nitrogen.

Brrrr!

Craig
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Old 24th Nov 2023, 11:12 am   #3451
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Default Re: The Audiophoolery Thread.

The 'Sirac-1' amplifier rung a bell with me.... ah yes, I bought this magazine BITD (aged 14) and this was probably the very first time I read about valve amplifiers - I never knew the design wasn't highly thought of...

Andy
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Old 24th Nov 2023, 11:39 am   #3452
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Default Re: The Audiophoolery Thread.

It started off all right, being based on a GEC design, but then he would fiddle with it.

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Old 24th Nov 2023, 11:45 am   #3453
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Default Re: The Audiophoolery Thread.

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Originally Posted by Beobloke View Post
I've often wondered if having a turntable in my listening room makes the sound worse when listening to vinyl but I can never prove it as, when I take the turntable outside the room, I can't play any records.
Well, you say that, but back in the seventies, one Edmund Ryan did just this - he moved his turntable and amplifier out into the hall, retaining the speakers in his lounge. The object of the exercise was to combat the effects of static on record noise in his centrally-heated house. I kid you not - he wrote it all up in Hi Fi Sound.
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Old 24th Nov 2023, 11:46 am   #3454
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Default Re: The Audiophoolery Thread.

It seems phools are easily parted with their money as I've just seen a used ecc83 selling for £800, and the auction hasn't finished.
If your going to spend that much on a single valve , I'm pretty sure there is a company somewhere in the world that could manufacture a brand spanking new one, and to your specifications for much less than £800.
For that much money , I'd want it to include a personal assistant that would hold the amp up off the ground so it didn't sit anywhere near the noise floor.
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Old 24th Nov 2023, 12:21 pm   #3455
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Default Re: The Audiophoolery Thread.

Well 21 bids and over two days left to run! Considering you can buy new ones (clearly with no audiophool foo) for £16 from https://watfordvalves.com/product_detail.asp?id=1306

And for £12.50 from https://www.stewmac.com/electronics/...3-preamp-tube/

Must check my stock of ECC83's and see if I can find a "MULLARD ECC83 LONG BLACK WELDED PLATE SQUARE GETTER 1600 1953"!

Craig
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Old 1st Dec 2023, 12:44 pm   #3456
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Default Re: The Audiophoolery Thread.

I've just had someone on the phone from Germany, wondering how he can interface his N**m amp (a 250DR - manual here

He was perplexed as to how he should connect the amp. On quick inspection, I thought that he only needed a standard XLR...but I was wrong! The XLR-balanced standard that we've all followed for decades isn't good enough for N**m's marketing department. They use an XLR to give the impression that it's balanced, but actually you have unbalanced going into one connector... Instead of 'pin 2 = Hot', you have 'pin 2 = Ch1'... And if you do this with a normal XLR cable, L-R crosstalk won't be great, so you need to buy their special cable that has shielded conductors for ($$$ kerching!).

Taken from link
Quote:
DAMAGE TO THE AMPLIFIER MAY RESULT IF “HIGH
DEFINITION” CABLE OR ANY OTHER SPECIAL CABLE IS
USED TO CONNECT THE LOUDSPEAKERS
Translation: "we have engineered the amp so that it's near the limit of stability. Unless you paid attention at school and know what capacitance means, you'll need to buy our cables ($$$$ kerching!) or it might oscillate and invalidate the warranty"

There ought to be laws against this kind of thing. This company gives British manufacturing a bad reputation. No Japanese product I've ever seen comes near to approaching the sheer cynicism of ^

And the price for this amp was around £7,000... The review on their site says "there was a noticeable turn-on thump". I am gobsmacked.

edit - one thing that's really funny is that the FR is given to 80Khz, yet it gives a -3dB tolerance... It's unstable, but it's not even flat to 80Khz... There were Japanese amps that were flat to 100KHz in the 1970s to within 0.5dB.
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Old 1st Dec 2023, 12:55 pm   #3457
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Default Re: The Audiophoolery Thread.

Indeed. On other Audio forums I've railed against marginally stable amplifiers. NVA is another one that requires their cables to be used as there's no output filtering or short-circuit protection.

These manufacturers are making a virtue (our amps are so finely wrought that they're not for 'ordinary' people) of inadequate engineering.

As far as I'm concerned, any amplifier that's not both unconditionally stable and fully short circuit protected isn't worth having.

S.
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Old 1st Dec 2023, 1:21 pm   #3458
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Default Re: The Audiophoolery Thread.

Quote:
Originally Posted by Craig Sawyers View Post
Must check my stock of ECC83's and see if I can find a "MULLARD ECC83 LONG BLACK WELDED PLATE SQUARE GETTER 1600 1953"!
If you can, the colour of the printing on the bottle will be sub-optimal most likely.

David
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Old 21st Dec 2023, 11:06 am   #3459
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Default Re: The Audiophoolery Thread.

Quote:
Originally Posted by knobtwiddler View Post

Taken from link
Quote:
DAMAGE TO THE AMPLIFIER MAY RESULT IF “HIGH
DEFINITION” CABLE OR ANY OTHER SPECIAL CABLE IS
USED TO CONNECT THE LOUDSPEAKERS
Translation: "we have engineered the amp so that it's near the limit of stability. Unless you paid attention at school and know what capacitance means, you'll need to buy our cables ($$$$ kerching!) or it might oscillate and invalidate the warranty"

There ought to be laws against this kind of thing. This company gives British manufacturing a bad reputation. No Japanese product I've ever seen comes near to approaching the sheer cynicism of ^

And the price for this amp was around £7,000... The review on their site says "there was a noticeable turn-on thump". I am gobsmacked.
Now, the problem with being an engineer is that you do spot design quirks like this, which is good. However, the distinct advantage of being an engineer is that you should also be able to determine whether these quirks actually matter, and not make sweeping generalisations based on something that's written on the internet.

I've owned a Naim Supernait amplifier for nigh on 15 years and it has the same sort of dire warnings in its handbook. However, not only was it the main amplifier in my hi-fi system for many years, but I also used it (and still do on occasion) as a reference when reviewing so it has been used for many hours on a huge number of different setups and powering all sorts of speakers from dinky little standmounters to floorstanding multi-way behemoths with the sort of phase response that makes your average amplifier run away and hide in a corner.

In all this time it has never complained, never overheated, never gone unstable and never died, or even hiccuped. And the craziest thing of all - I've never used Naim speaker cables with it! The actual truth is that any sensible speaker cable will be fine with a Naim amplifier (so, don't try using those strange woven oddities that have high inductance - but I'm sure no one here would be daft enough to do that anyway, regardless of their amplifier) and the only caveat is to make sure the length of cable isn't too short - as long as there's a couple of metres on each channel then it will be absolutely fine.

Even the switch-on thump is fairly mild compared to some other amplifiers I've owned (Rogers Ravensbourne, anyone?!).
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Old 21st Dec 2023, 11:15 am   #3460
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Default Re: The Audiophoolery Thread.

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Originally Posted by Beobloke View Post
In all this time it has never complained, never overheated, never gone unstable and never died, or even hiccuped. And the craziest thing of all - I've never used Naim speaker cables with it! The actual truth is that any sensible speaker cable will be fine with a Naim amplifier (so, don't try using those strange woven oddities that have high inductance - but I'm sure no one here would be daft enough to do that anyway, regardless of their amplifier) and the only caveat is to make sure the length of cable isn't too short - as long as there's a couple of metres on each channel then it will be absolutely fine.

Even the switch-on thump is fairly mild compared to some other amplifiers I've owned (Rogers Ravensbourne, anyone?!).
You mean Low inductance, high capacitance!

Although of course one can use these marginally stable amplifiers if one's careful, but why should one need to be? There are many other amplifiers that are unconditionally stable and fully protected so why not use one of these?

Poor engineering is poor engineering, and should be called out, especially in a premium-priced, heavily promoted product.

S.

Last edited by Station X; 21st Dec 2023 at 12:54 pm. Reason: Quote fixed. Please use the preview button before submitting a post.
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