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Old 1st Jun 2022, 6:17 pm   #2761
knobtwiddler
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Default Re: The Audiophoolery Thread.

Does this qualify as audiophoolery?
https://retrogearshop.com/collection...86-tube-spares

$280K

The meters are still made and you can get them with the Fairchild logo. The only parts I can think of that are unobtainable are the transformers. However, if you waited long enough, you could probably find them over a period of years. Were you really cynical, you could easily make the cans and fit Sowter's clones inside (electrically correct). If you potted them, who would know?

The knobs are also made as replicas, but they aren't perfectly identical. The knobs and TFs are the only parts I would have serious hassle finding. Not that I'm saying it's a fake. It's most likely an original minus any patina. Where's the studio history? Even if it came from a small-time studio, for something that costly, you'd usually have a little story about some back street facility buying it in 1959, right?

And it doesn't have RCA valves...it has JJ replicas!!!

Tim de P made his take on the 660 / 670 in the eighties. He wisely realised that some of the valves and interstage transformers weren't in the path, so you could keep the path valve and make the sidechain electrically identical, but using silicon. Even his clones are now collectors' items.
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Old 1st Jun 2022, 9:03 pm   #2762
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Default Re: The Audiophoolery Thread.

Post No.2761 wins!
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Old 1st Jun 2022, 9:13 pm   #2763
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Default Re: The Audiophoolery Thread.

Someone spends $280,000 on a compressor/limiter to improve the fidelity of their hifi?

And there's me thinking that taking such a thing out would be the improvement. Once you've taken it out, you then have the thing to sell, if you can find a mug.

These things have their purpose in limiting the modulation of a transmitter so that a signal is prevented from causing energy to stray into the next door channel and thereby bringing down the wrath of the FCC on the perpetrator. A good one of these sorts of things does the job with least audible damage to the signal.

But if you're not a broadcast station then you do not need one.

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Old 1st Jun 2022, 10:20 pm   #2764
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Default Re: The Audiophoolery Thread.

AND it uses really crappy JJ Tesla valves, made in russia. I am aware it rained, but I watched the rain, so I didnt come down with it.

Joe

P.S. couldnt you just run your signal through your 1970 Sanyo cassette recorder with ALC ?
( automatic level control )
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Old 1st Jun 2022, 11:59 pm   #2765
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Default Re: The Audiophoolery Thread.

About 9/10 of these compressor-limiters are seen in posh recording studios such as Abbey Road (who apparently have a safe full of RCA and Telefunken tubes, bought before prices went mad). They are sometimes used in mastering studios.

The Fairchild seen here is regarded as having mythical properties, hence Tim d P's recreation in the 80s. There have since been many clones, and it's a popular clone for DIY-ers to attempt.

I was used to seeing them for £25-30K, and much as I wouldn't pay it myself, could understand the cost as they are regarded as a status symbol (along with the U47 mic) in high-end studios. The asking price of $280K is on another level entirely... I actually think someone might pay $100K for a decent one, but this one's been over-restored and - weirdly - the ad doesn't mention its provenance. I think you could fake the whole thing bar knobs and transformers. If they are potted, then you could buy the Sowter clones and put them in fake cans... The knobs are rare, but they have been recreated convincingly.

Note how clean the bezels on the meters look... See here: https://www.don-audio.com/Vintage-Si...AIRCHILD-Model

I don't think it's a fake... But if you were of that inclination...

He has some of the knobs as well: https://www.don-audio.com/Fairchild-Knobs-Kit
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Old 2nd Jun 2022, 12:56 am   #2766
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Default Re: The Audiophoolery Thread.

In a recording studio, it will be used ahead of some process with restricted headroom, either saturation in a tape recorder or the cutter head on a disc lathe hittng its end stops.

So it performs a necessary function.

Similar care is also needed to keep signals within the gamut of ADC converters for all digital media.

The one person who doesn't need on is the audiophile sitting listening at home. It can be presumed that all he can listen to whethe broadcasts, records, tapes, CDs or sound downloads of any format, will have had their dynamic range managed (hopefully carefully!) before he ever got them. There is no point in doing it all over again, it's already been done to an extent tailored to the specific medium. It's not a process where more is better. Less is better, but doing none at all can cause difficulties. Skilled engineers will try to keep within a headroom limitation, and try to do the least damage in doing so.

Hmm, if the faking was done precisely, and the magical makes of valves were fitted, there shouldn't be any unavoidable difference from one built by Fairchild. But once people know there is any sort of difference, the magic dissipates.

David
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Old 2nd Jun 2022, 6:54 am   #2767
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Default Re: The Audiophoolery Thread.

Unless I am missing something here, it is AM compression. Yes amplitude. It squashes the tops and bottoms so the transmitter/tape deck/ seedie recorder, etc doesnt see peaks that it cant handle.
They were required and still are. IF you cant handle the peak power that the receiving medium cant handle.
I used many of them in AM radio stations, Small boxes perhaps 3 U high and 3U across.
I dont remember the brand, but they just limted the revvy disk jockey. EVEN if his desk VU showed +20, only 0 dV came out.


Joe
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Old 2nd Jun 2022, 10:12 am   #2768
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Default Re: The Audiophoolery Thread.

The Fairchild won't have seen use in broadcast since the 70s. By that time, the likes of Orban had more sophisticated (and fool-proof) devices for limiting. The Optimod is far more sophisticated and commercially-viable in terms of making the music (or adverts...) grab the listener's attention.

You may see the occasional Fairchild in a mastering house, but more mastering engineers will likely opt for Tim d P's Fairchild recreation, as it's quieter and the valves are cheap (6BA6 gain element vs 8 x unobtainium RCA 6368).

Most places I've seen with a 670 tend to be recording studios. As I said before, it's a marque of a high-end studio, along with U47 mic and Neve desk. It's typically used for tracking live instruments, or compressing overall sub-mixes / final mixes. Dynamic compression is a necessity in music production, and folklore has it that the 670 does it best. Studio engineers / producers are looking for 'glue' that keeps the various elements sitting nicely together in the mix, where quieter parts don't get drowned out and louder parts don't do the drowning.

Sadly - and quite poignantly to this thread - hyper compression is highly prevalent in modern releases, where they sound as if they've been recorded from radio right off the CD or vinyl. The 'loudness race' shows no sign of abating. You can compare releases made decades ago to their recent re-releases to see how widespread 'pancaking' is. I believe it's a reason why a lot of original vinyl is so pricey these days (it's rare for me to see a record below £100 these days if it was made in the 60s or 70s).

I believe Bob Orban was bemused when he discovered recording studios were using the Optimod to make records sound louder, as he'd never designed it as such. One of the reasons why 60s / 70s records sound good on the radio is that they weren't squashed too badly in the first place. Modern records are ready squashed before they hit the Optimod, making for a processed cheese sound. Read about Orban here:

https://en.wikipedia.org/wiki/Orban_(audio_processing)
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Old 2nd Jun 2022, 11:24 am   #2769
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Default Re: The Audiophoolery Thread.

More recent (rock) recordings basically don't deviate by more than a few dB from the end stops on the (soft) VU meters on the front of my Logitch Transporter streamer. It sounds very unsatisfying.

And you're right, older vinyl records and faithful CD transcription have really good dynamic range. Just been listening to Chesky CD88, Symphonie Fantastique (Berlioz). From a solo clarinet through to truly hair raising climax. Then there is the Telarc Tchaikovsky 1812 on vinyl. In recording that they had a real problem in adjusting levels so it was on the hairy edge of tracking. The cannons are a test of tracking ability of a cartridge. Lesser (but still expensive) cartridges can be thrown clear of the groove. Truly hair raising when tracked properly. Groove image of the cannons attached.

Craig
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Old 3rd Jun 2022, 1:02 am   #2770
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Default Re: The Audiophoolery Thread.

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Originally Posted by Radio Wrangler View Post
The one person who doesn't need on is the audiophile sitting listening at home.
In fact it could be argued that the audiophile has more need of an expander to counteract the over compression used on some releases. Dbx made them for the home in the 1970s and I have a model 117 here which features a continually variable ratio control ranging from 1:2 expansion to 1.4:1 compression.
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Old 3rd Jun 2022, 8:48 am   #2771
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Default Re: The Audiophoolery Thread.

Interesting bit of kit. Two VCA's and a several 741's. Typical of the era, single sided board. Poking around there are those who hot rod it by swapping opamps for something more recent.

Back in the day, at around the same era as the 117 I built the Practical Wireless Texan. I remember that the most expensive bits were the opamps - 741 and 748 - were 60p each. So an eye popping £3.60 for the opamps (about £40 in today's money).

Frustrated by the slow speed that ferric chloride etched, I read somewhere that hydrochoric acid and hydrogen peroxide were faster. I was the chemistry lab-boy at school (setting up class preps, making sure reagents were mixed up etc) so I had access to the chemicals. Took in my laboriously made board, using the pens you could buy for the task. And watched horrified as the witches brew stripped the board clean in seconds.

Went back to ferric chloride after that!

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Old 3rd Jun 2022, 10:03 am   #2772
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Default Re: The Audiophoolery Thread.

The true Audiophool wouldn't want any of that in the signal path as it would surely contaminate the audible perfection of their program source, which if I understand the mentality is never to be questioned.

Or so I was once educated by one of the breed as he was demonstrating his (claimed) £40,000 HiFi set up with a recording of Cher's Album "Believe".

You could hear the digital converter noise with all its creamy crispness so maybe they're on to something.

This guy, (who's name incidentally is Guy, a perfectly nice individual), claimed that true perfection will only be attained when the source can be connected directly to his speaker system, dispensing with the superfluous intermediate technology.

So you think the speakers are perfection?

His answer was, "Do you know how much they cost?"

I laughed so hard, Guy thought I was choking!

That moment of pure Schadenfreude is where my mind takes me whenever I hear the stylings of Cher, (and the studio's autotune equipment).
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Old 3rd Jun 2022, 12:29 pm   #2773
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Default Re: The Audiophoolery Thread.

A source that can drive speakers directly without intervening electronic boxes?

You've now conjured-up an image in my head of 20 ft diameter tungsten-carbide records spun by a 5HP motor using a monster moving coil cartridge with the Cullinan diamond (recut) as its tip, driving speakers directly. RIAA would have to be taken care of in the speaker design - probably horns for efficiency.

Record cutting lathes would need to move to a grinding process with more diamond stuff in play.

I see the main problem as getting the volume from the speakers to outdo the chatter from the stylus.

Reassuringly expensive, or what?

David
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Old 3rd Jun 2022, 1:21 pm   #2774
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Default Re: The Audiophoolery Thread.

Funnily enough, the Fairchild limiter uses (8 in total) 4 x 6386 dual triodes in parallel p/ch to feed the O/P transformer, so it can drive a speaker quite happily!

I seem to remember reading in (S0S magazine) that's Cher's track was mixed in a Mackie 8-Bus console... (a budget console that's about as cheap as an 8-bus gets - although it is extremely quiet, more so than most grillion dollar consoles). The Mackie was famously copied by B******r. They copied it so comprehensively that the clone even had the same fault, i.e. crosstalk in the sends... When Mackie sued in London, the judge couldn't award in their favour as they had neglected to register the design...
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Old 3rd Jun 2022, 7:32 pm   #2775
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Default Re: The Audiophoolery Thread.

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Quote:
Originally Posted by Radio Wrangler View Post
The one person who doesn't need on is the audiophile sitting listening at home.
In fact it could be argued that the audiophile has more need of an expander to counteract the over compression used on some releases. Dbx made them for the home in the 1970s and I have a model 117 here which features a continually variable ratio control ranging from 1:2 expansion to 1.4:1 compression.
Hear Hear! Not just the audiophile, either. For anyone interested in experimenting in this area, there is software available. At plugins4free, for example.
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I filtered the new Adele 25 album which is heavily, awfully compressed with unbearable distorted peaks if played loudly. With Relife you can hear it loudly without distortions. Have a look at the wav-files in Audacity hitting the boundaries and after Relife when there is headroom. It is an amazingly improving filter that repairs the follies of some music studios.
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Old 3rd Jun 2022, 10:42 pm   #2776
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A source that can drive speakers directly without intervening electronic boxes?

You've now conjured-up an image in my head of 20 ft diameter tungsten-carbide records spun by a 5HP motor using a monster moving coil cartridge with the Cullinan diamond (recut) as its tip, driving speakers directly. RIAA would have to be taken care of in the speaker design - probably horns for efficiency.

Record cutting lathes would need to move to a grinding process with more diamond stuff in play.

I see the main problem as getting the volume from the speakers to outdo the chatter from the stylus.

Reassuringly expensive, or what?

David
Possible that it would need its own correction specification, I don't think the RIAA would help boost the top end quite enough?

Well, I did suggest if less was better, a ceramic cartridge feeding a pair of piezoelectric speakers by that theory would sound superb, if a little db light.

(But that would be sure to need the turntable in a sound proof box.)

Another discussion with a Phool was going quite sensibly, regarding the pointless striving for ever better fidelity from the electronics; when the speakers, and ultimately the lugs of the listener were never going to do any of it justice.

The Phool then seriously suggested cochlea implants may be the way forward.

I think he was sober.

Please tell me no one has ever tried doing that for the sole purpose of musical appreciation?

Of course that would stop the horrible sound of tsss ..tsss ..tsss from the iPod earphones worn by the passenger in the next seat on the train, if not their occasional breaking into tuneless karaoke.
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Old 4th Jun 2022, 7:55 am   #2777
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Default Re: The Audiophoolery Thread.

You know those Victorian/Edwardian photographs of very starched-looking people? Well, because of the very slow-acting photographic plates, the photographers used to have wooden braces placed behind their subjects to hold their heads steady.

I've sometimes thought that these things should make a comeback for audiophool listening because any movement of the head will affect stereo imaging, risk moving into room nulls and cause doppler effects. The modern version would have to have spiky feet, of course. Maybe spikes at the top for a really secure grip. Can art really be art if you're not suffering for it?

David
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Old 4th Jun 2022, 8:08 am   #2778
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Default Re: The Audiophoolery Thread.

That is Dick Burwen's position on audiophile tweaks. You carry out some tweak, and sit back down to listen. But because your head is now in a slightly different position, the frequency balance has changed.

This is Burwen's biography from his site http://www.burwenaudio.com/Biography.html

"Audible tweaks that cannot work" in Linear Audio V3, April 2012.

Craig
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Old 4th Jun 2022, 9:58 am   #2779
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Default Re: The Audiophoolery Thread.

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Originally Posted by G.Castle View Post

This guy, (who's name incidentally is Guy, a perfectly nice individual), claimed that true perfection will only be attained when the source can be connected directly to his speaker system, dispensing with the superfluous intermediate technology.

.
I thought that source to speaker was already widely available in a wind up gramophone, no superfluous electronics in the way!
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Old 4th Jun 2022, 10:07 am   #2780
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Default Re: The Audiophoolery Thread.

That’s it… weird image of the day

I now have the image in my mind of a Terry Gilliam like cartoon with Victorian/Edwardian men held in bizarre wooden frames subjectively listening to some ‘steam punk’ single ended Class A creation.

Terry

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You know those Victorian/Edwardian photographs of very starched-looking people? Well, because of the very slow-acting photographic plates, the photographers used to have wooden braces placed behind their subjects to hold their heads steady.

David

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