Distortion = Dynamic Expansion = YAY!

A while back, I bought two Heathkit monophonic, vacuum tube, integrated amplifiers at a yard sale. They were so old that they had inputs for mono ceramic phono cartridges. Having no use for them as integrated amps, I crudely gutted the preamplifier circuitry, leaving what was left as a power amp.

I plugged the pair in and invited an audio amigo over to hear the results. We were gobsmacked. The little amps sounded more alive and dynamic than anything we’d previously heard. The question was why?

The answer turns out to be “psychoacoustics.” Our ears interpret distortion as “louder.” Since the amps have so little wattage, and since their primarily second-order distortion rises pretty much linearly with output, the audible effect is a dynamic range expansion that sounds like a million watts.

When listening, however, your ears don’t hear distortion. Instead, they hear dynamics galore (and a VERY exciting presentation it is, indeed).

I don’t have the equipment to measure these amps, but I’m not looking a gift horse in the mouth, either. I keep them on the rack to embarrass audio amigos who become enamored of the lie that “more watts are always better watts.”

My 12-watt Heathkits floor them EVERY TIME!

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Well, more watts may not always be better watts, but more watts is always better.

LOL, @Marian - You obviously haven’t heard the Heathkits…

Even with modern solid-state amps that don’t begin to distort until they approach their maximum power limit, the average listening level is less than one watt! This isn’t an opinion, it’s a FACT. If you want to power stadiums or throw dorm parties, then you’ll need more watts. But the average home listener would be fine with any amplifier from 10 to 50 wpc. Anything more is a waste of money.

Prolonged vs transient output. Not the same thing. Nobody needs more that a few watts prolonged, but life-like rendition of the explosion of a balloon would need more transient power than any amp can deliver

And distortion sounds exciting but it’s not what was recorded, so typically not what we want in hifi.

Edit: Can’t help but find it a bit funny in the light of the FLAC vs WAV Diskussion

Power is logarithmic, so the numbers get pretty big pretty fast, also it’s a measure of consumption - and you may not need to consume it. Efficient speakers will need far less to get moving. But, I’m happy for you, enjoy the amps :slightly_smiling_face:

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Hi @Suedkiez -

I’ll agree that power demands are far different for prolonged vs. transient use. A football stadium used for a concert might well require hundreds of watts on a prolonged basis. But for transients, you’re entirely right - no amplifier can supply sufficient power for a loud, clean transient. In fact, no loudspeaker could withstand that power even were it available. So you’re saying that ALL amplifiers are likely to either clip on transients (or never develop the power to accurately play the transient since the sound is so short). I’ll agree.

That being the case, every amplifier is likely to distort in your “balloon pop” example. To which I reply “so?” If distortion is “acceptable” in a balloon pop, why is it unacceptable in other loud transients (which is what we’re talking about in my Heathkits)? The Heathkits have more than sufficient power to play very cleanly on 99.9% or more of the music that they play. It’s only on louder transients that they distort - and even then that distortion is inaudible as “distortion.” It merely sounds like “much louder music transients.”

Is it “what was recorded?” Well, that’s up for debate also. Remember that the pre-production audio gear was ALSO peak-limited in the wattage that it could put out. So there’s probably a touch of distortion on louder transients be they either digital or on vinyl. I’d question your assertion that peak transient distortion can occur only in the playback chain.

And finally, the FLAC vs. Wave debate. To my ears, and on my equipment, wave files sound audibly better. Do they sound better than FLAC? I think so, but I’m not entirely sure. I am sure that wave files sound audibly better than ALAC files using the Apple compression scheme. No question on that one… So since I made that discovery, I’ve avoided any and all CODECs that include any compression at all (including FLAC). If others can hear no difference, then they’re welcome to use any CODEC they want. But I’m sticking with wave until I hear something better.

Merry Christmas!

My point was that “nobody needs more than 50 watts” is simply not correct. We lack the means to reproduce all sounds accurately and most hifi fans would like to have them.

As for the WAV, it’s simply weird to obsess over at worst minuscule differences caused by the FLAC decoding load and then eulogize about how great heavy distortion sounds. It makes no sense.

But I’m out.

Well, most modern speakers have 90 or more decibels at one watt at one meter. That’s LOUD. Most of us don’t listen that loudly (and those of us who do are destined for hearing loss). So I’ll revise my statement to “most of us need no more than 50 watts.”

Obviously, if you have some obscure speaker system that puts out low 80 decibels at one watt, then you will probably need more. If you have some obscure speaker system that drops to 2 ohms or below at parts of its frequency range, then you will probably need more. If you like to listen to music or movies at earsplitting levels, then you will probably need more. And if your listening room is auditorium sized, then you will probably need more. Such is life.

And as I thought I made clear, the differences between compressed ALAC and WAV are in no way “minuscule.” Are the differences between FLAC and WAV similarly significant? I haven’t done enough comparative listening to say, but I will say that I’m universally wary of ANY compression scheme.

I also don’t listen to my Heathkits all the time. I keep some 150-watt solid state mono blocks on my equipment stand as well. I’d say that I listen to the higher power amps 90% of my time and the Heathkits no more than 10%. But on some music, the dynamic expansion of the Heathkits can be magical.

Glenn

Again, you need to learn how power requirements for transients works. But whatever, I have no hope because you prefer pontificating without understanding. It’s fine, your choice, I have set you to ignore and won’t bother you

I contend that it is you, @Suedkiez, who prefers to pontificate, and profoundly dislike anyone who disagrees with you. You choose to ignore me. No problem.

oh, c’mon

I do not get any numbers, math, ohms or watts! But how am I going to learn if not by following those kinds of posts. (maybe google but I prefer you). No need to get grumpy

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I have a Devialet 440 which is very “clinical”. Occasionally I’ll try something warmer, perhaps tubes, but after a few days, I appreciate the Devialet’s clarity more. That’s the great thing about this hobby :slight_smile:

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My first turntable had a 10W integrated power amp and I don’t remember needing more power. Still, with more power, you have less distortion at normal listening levels and less chances for clipping - which could damage speakers.

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This is simply not true. Absolute statements like these really should be avoided. When you already have more watts than you need, more watts are not better.

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Ok what device would I need to measure how much power I’m using? Lets say I now my pream specs and my amp specs (maybe I need speaker specs also)… can I do the math to find out how many watts I use?

Maybe a dumb question, in that case you can ignore me pls

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An easier way to find out how many watts you are using is with a sound pressure level app for your iPhone. Turn your music up to the level you would normally listen at. Then hold your phone about three feet away from the speaker (about one meter). Then read the sound pressure level in decibels.

Look up your speakers’ sensitivity on the internet or in your owner’s manual. That sensitivity is given in the standard measurement of “one watt at one meter.”

This is not an accurate test because you’ll have two speakers playing and you’re only measuring one, but it’s accurate enough for what we’re trying to measure.

If your iPhone measurement is less than the speaker’s “one watt / one meter” sensitivity, then your normal listening level is using less than one watt. In 99.9% of all cases, you ARE listening at less than one watt.

Again, this is a crude test that ignores some factors. But it is accurate enough to get a rough idea of how much power you’re using.

If you want to crank things up to “as loud as I’ll ever listen” and then do the iPhone test again, you’ll probably be using more than one watt. How much more gets into some math we don’t want to bother with here, but the “one watt - more or less?” test is a useful one.

Glenn

Postscriptum - The only “dumb question” is the one you don’t ask.

Thanks :slight_smile:

Can I measure each speaker one at the time (@ same volume) and add? I did turned off the subs

Now while I do not have an Iphone I did use a UMM-6 with REW and I get between 75 and 90 db for normal listening volume

Searched the speakers: 90dB/2.83V/m.

(all the specs are Two-way, reflex-loaded, floorstanding loudspeaker. Drive-units: High Velocity Folded Ribbon (HVFR) tweeter, two 6" woofers, four 8" planar passive radiators. Frequency range: 26Hz–35kHz. Sensitivity: 90dB/2.83V/m. Nominal impedance: “compatible with 8 ohms.” Recommended amplification: 15–400Wpc)

Crank it up I want :slight_smile: I get between 93 and 98 (over 100 I’ll have the neighbours at the door)

Thanks, fun to do.

That’s an expression. It means “don’t skimp on power if you can”.

Exact power vs. SPL is a multi-part calculation involving the speaker’s impedance, its acoustic sensitivity, and a logarithmic calculation of decibels.

No, you can’t just double the decibel level for the second speaker. If you’re equidistant from both speakers, the decibel increase for adding the second one is either plus three or plus six (I once knew, but haven’t done the calculations in so long that I’ve forgotten).

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