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1
I just released faac 1.29.5 with a few real changes.
Encoding is definitely much faster and quality may also be better with many samples, definitely worth trying.

Also, I just noticed there is noise coding available and it always was a part of standard AAC LC.
Apparently I totally missed it back in the days.
I will try to develop this thing for upcoming releases, it can give a real quality boost, especially at lower bitrates.
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Audio Hardware / Re: Interview Time
Last post by Arnold B. Krueger -
And just to be clear, it is not the tubes per se that result in the distortion, but the transformer that matches the high impedance of the tubes to the low impedance of the speakers.

Kinda-sorta.

I've studied this issue extensively over the years, and I agree with several of the points that Carver raised in the video. If you cut though the pseudo science, the most audible aspect of vintage amps is their generally higher source impedance.

Carver alluded to, and measurements and tests confirm that while tubed amps tend to be much more nonlinear at full output, at typical listening levels, the tube distortion is relatively low.

 In some relatively well-engineered tube amps like McIntoshes, the nonlinear distortion is below audibility at any reasonable in-spec operating level.  Even in the boutique freak-show SETs, at the power levels that most people listen to these things to at, the nonlinear distortion is still probably inaudible.

PDQ comments about output transformers is true, but their limitations come in two ways. Transformers can be free of audible distortion if they are well-designed and used at relatively low levels. But if they are undersized or otherwise poorly-designed, they can have audible distortion, particularly at low frequencies.   They limit ultimate performance via another route - their phase shift at high and low frequencies. This makes applying enough inverse feedback tricky or impossible.

However, tubed amps and even some legacy SS  amps might have source impedance issues. Even nominally good SS amps often have stability-enhancing RL networks at their outputs and outside the feedback loop that cause potentially audibly rising source impedance at high frequencies near the top of the normal audible band.  Any legacy SS amp that has a single power supply for its output stage generally has a large DC blocking capacitor that will interact with some woofers to create relatively large amounts of bass boost (YES, BOOST!)  - often several DB in the lowest normal octave.

Often, the high source impedance of a tube amp is well-simulated by means of a simple wirewound series resistor on the order of several ohms and several watts. Or. use suitably long very thin speaker cables.


3
Audio Hardware / Re: Interview Time
Last post by pdq -
And just to be clear, it is not the tubes per se that result in the distortion, but the transformer that matches the high impedance of the tubes to the low impedance of the speakers.
4
I'm another soon-to-be ex-Photobucket user, as soon as I've downloaded those images I want to keep. Suggestions for free image hosts, especially with sites that load quickly, would be gratefully received.
5
Yet another me-too service provider with a failed free-first, jack up prices later business model. It never works.
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Opus / Re: opusgain scanner implementation status
Last post by Surfi -
::

+1 ... exactly my problem, I'm using GMMP too. Thank you for posting this!

Greetings, ...

::
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That software has been somewhat debunked.  As an audio professional, I would never trust it in a million years.  Here is a thread about it:
https://hydrogenaud.io/index.php/topic,111582.0.html
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General Audio / Re: Powering Up Audio System
Last post by Paul_ 2012 -
For commercial banks of LV lighting (12v dichoic) soft starters were sold to limit the inrush current, smooth out the voltage and extend the life of what used to be an expensive lamp when they were first developed, not sure how successful this bit of kit was. Voltage spikes and current inrush was a stated cause of early lamp failure. Would something like a soft starter be available/useful, soft starters are also used in power tools such as single phase table saws to stop them tripping the breaker.
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Audio Hardware / Re: Interview Time
Last post by polemon -
it's more of a theoretical exercise i guess. if the whole point of tube amps is their particular distortion profile, then wouldn't it be much cheaper and easier to simply emulate those distortions with some DSP and a proper solid state amp? it's pretty much what Carver did himself as that wiki i linked to shows...
It might be easier to emulate those and cheaper to run them, but the problem is: they wouldn't sell. [...] Having an "emulated amp" is just not gonna sell.
In the ProMusician world a lot of profiling (guitar)amps exist, e.g. https://www.kemper-amps.com/. And they sell good.

Sure, in that sort of niche market, they might sustain a bit, but it'll never be the main target consumer base. Some producers might want to emulate tube amp sounds for period correct film sounds tracks, etc. but they'd used software for it.

What we're talking about here is "creating the tube sound, without actual tubes" for the general consumer. Most consumers wanting tube sound, don't want just tube sound, they want tubes, and the sound kinda comes with it. Selling tube amps is about selling nostalgia and elitism, not about perfection. You could sell function correct emulated tubes, but you wouldn't sell the nostalgia and elitism, etc.

The tube aficionado sort of audiophile market is already kinda small, people being OK with "faked tubes" would be an order of magnitude or several of those smaller.
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Audio Hardware / Re: Interview Time
Last post by silverprout -
mistake. can you delete please?