See Richard Burwen's 1945 paper:
http://www.burwenaudio.com/OBJECTIVES_IN_HIGH_FIDELITY_AMPLIFIER_DESIGN_1945.pdf
http://www.burwenaudio.com/OBJECTIVES_IN_HIGH_FIDELITY_AMPLIFIER_DESIGN_1945.pdf
Why produce an amplifier with tone controls when the well-heeled consumer can be persuaded to experiment with expensive interconnects and speaker cables in pursuit of the same goal? 🙄
In 1945 maybe but it wasn't until 1947 that D.T.N Williamson published his =0.1 % distortion audio amplifier circuit that a "leap forward " occurred in audio.
I stopped building audio amplifiers with tone controls long-long time ago.
I am a bit of a "minimalist " - don't like "presence/loudness" switches.
DC connected and yes you can build an audio circuit with extremely small offset if you check out each component before you install it.
Yes it takes much longer -yes it might upset some but patience and accuracy are worthwhile actions.
Old tube radio,s idea of a "tone control " was a "top cut " capacitor across the output transformer,s input -- as they said in the 30,s -quote-
A "lovely " mellow sound issued from the radio when the control was turned bringing "joy and happiness " to the faces of the listeners - end quote.
Yes it would do if all that was left was 1 KHz or so.
I stopped building audio amplifiers with tone controls long-long time ago.
I am a bit of a "minimalist " - don't like "presence/loudness" switches.
DC connected and yes you can build an audio circuit with extremely small offset if you check out each component before you install it.
Yes it takes much longer -yes it might upset some but patience and accuracy are worthwhile actions.
Old tube radio,s idea of a "tone control " was a "top cut " capacitor across the output transformer,s input -- as they said in the 30,s -quote-
A "lovely " mellow sound issued from the radio when the control was turned bringing "joy and happiness " to the faces of the listeners - end quote.
Yes it would do if all that was left was 1 KHz or so.
Surely you speak in jest! Even if you could design a system with a flat frequency response, and you cannot if only because the speakers alone would never have a flat frequency response across the audio band, your listening room cannot have a flat frequency response; ergo, tone controls are absolutely necessary.
You appear to have confused sarcasm with jest - you must not have noted my smilie!
I use tone controls for the very reasons you state, as well as to compensate for the different tonal characteristics of my LP and CD recordings.
I use tone controls for the very reasons you state, as well as to compensate for the different tonal characteristics of my LP and CD recordings.
Indeed, tone controls are definitly needed to tailor the sound due to room acoustics, system/speaker signatures, and finally, personal preferences.
They've always been standard equipment on just about anything in the "better' audio department.
The nonsense of purists detesting tone controls are just highly biased and ignorant blabbering.
They've always been standard equipment on just about anything in the "better' audio department.
The nonsense of purists detesting tone controls are just highly biased and ignorant blabbering.
Tone controls are both necessary and insufficient.
Tone controls are nice to make the music sound like what you think it ought to sound like. Maybe you don't want to listen at realistic sound levels all the time. Or at least the neighbors would prefer you didn't. Fletcher-Munson curves indicate that at lower volumes, you have to re-equalize the audio--you have to add some bass and some high treble--to make the all the frequencies have the same perceived balance as at high volume. Unfortunately, you have to re-adjust this every time you change the volume.
Loudspeakers have roller-coaster frequency responses, and with a real-time spectrum analyzer and white noise, you can flatten this with a nice 3 or 4 band parametric EQ. Loudspeakers with multiple drivers do have one problem that EQ cannot fix, and that is comb filtering. Constructive interference can be fixed, but destructive interference cannot. Sharp crossover networks, or active and DSP crossovers, help.
Acoustically, you have the same interference problems between loudspeaker output and reflections from surrounding surfaces. Constructive interference can be addressed, but destructive interference causes a complete dropout in the audio at a specific frequencies, and no amount of boost can bring it back.
I usually use the "loudness" button on the preamp when I want to listen at low volumes, and it helps, but it's not precise, it's just better. I have a pair of Kanto KU-4 speakers on my PC. The silk dome tweeter sounds nice, but I feel they designers balanced its output a few dB too low. I simply turn up the treble a notch or two, and it sounds mostly OK. Is it perfect? No, but the tone control makes it better. It helps that these can be digital effects, with no audible insertion problems.
Tone controls are nice to make the music sound like what you think it ought to sound like. Maybe you don't want to listen at realistic sound levels all the time. Or at least the neighbors would prefer you didn't. Fletcher-Munson curves indicate that at lower volumes, you have to re-equalize the audio--you have to add some bass and some high treble--to make the all the frequencies have the same perceived balance as at high volume. Unfortunately, you have to re-adjust this every time you change the volume.
Loudspeakers have roller-coaster frequency responses, and with a real-time spectrum analyzer and white noise, you can flatten this with a nice 3 or 4 band parametric EQ. Loudspeakers with multiple drivers do have one problem that EQ cannot fix, and that is comb filtering. Constructive interference can be fixed, but destructive interference cannot. Sharp crossover networks, or active and DSP crossovers, help.
Acoustically, you have the same interference problems between loudspeaker output and reflections from surrounding surfaces. Constructive interference can be addressed, but destructive interference causes a complete dropout in the audio at a specific frequencies, and no amount of boost can bring it back.
I usually use the "loudness" button on the preamp when I want to listen at low volumes, and it helps, but it's not precise, it's just better. I have a pair of Kanto KU-4 speakers on my PC. The silk dome tweeter sounds nice, but I feel they designers balanced its output a few dB too low. I simply turn up the treble a notch or two, and it sounds mostly OK. Is it perfect? No, but the tone control makes it better. It helps that these can be digital effects, with no audible insertion problems.
Why set out to make a contentious point about tone controls in the solid state power amplifier forum? Is it because of the larger audience to read all the likely tub-thumping and discord?
Surely the use or not of tone controls derives from hi-fi audio principles. Depending on the emphasis for technical or ethical discussion, it belongs in one of the Source and Line Level forums (tone controls typically operate at line level) or in the lounge forum.
Perhaps as a recent member you haven't yet checked out the many other categories of this huge audio forum. The spread of categories covers a mind-boggling mass of topics but organised as they are, can be a great resource and well worth a search of thread topics to see what best fits and where.
Surely the use or not of tone controls derives from hi-fi audio principles. Depending on the emphasis for technical or ethical discussion, it belongs in one of the Source and Line Level forums (tone controls typically operate at line level) or in the lounge forum.
Perhaps as a recent member you haven't yet checked out the many other categories of this huge audio forum. The spread of categories covers a mind-boggling mass of topics but organised as they are, can be a great resource and well worth a search of thread topics to see what best fits and where.
By not including one in the pre-amp you can then sell the buyer a stand-alone "tone control system" and generate more income.
I still have my old graphic equaliser as part of my party system, those twinkly LED light bars add a real 80s glamour
Indeed, a "pursuit" that never seems to satisfy, or end.
The rabbit hole of delusion runs deep.
If the speakers are full range then you probably dont need a tone control.
In 1980 I built a Maplin disco with their amp and their record decks
I used 4 off Fane 12"-50WRMS speakers but they just went to 3KHz.
I found a mixer with tone controls lifted the top end a bit.
In 1980 I built a Maplin disco with their amp and their record decks
I used 4 off Fane 12"-50WRMS speakers but they just went to 3KHz.
I found a mixer with tone controls lifted the top end a bit.
Tone controls can and have been built into power amplifiers: Harman Kardon HK610, for example, so this thread is not out of place in this forum.
Not so: your full-range speakers are very unlikely to have a flat frequency response, something that is undesirable anyway since your listening environment is also very unlikely to have a flat frequency response.
Speakers dont have a flat response typically.
But a properly designed system would allow for this with correct cross overs or eq.
But a properly designed system would allow for this with correct cross overs or eq.
Doing that is not necessary, precisely because the curves of F.M. show the decrease in the sound intensity perceived by the human ear in high and low frequencies when listening at low volumes.
You can leave the Loudness knob on, it won't have any effect when listening to high SPL. The same if you adjust with the bass and treble controls at low volumes to your liking, then turn it up and try to hear differences if you love "flat". It is not that the circuit has broken down, it is our ears that have this characteristic behavior.
That is why those of us who listen to the real volumes of musical instruments do not need tone or loudness controls. It's like going to a chamber music concert and asking the musicians to lower the intensity of their performances because we are not used to that sound reality. Absudo, right? And furthermore, we, the authentic "golden ears", do not understand that "WAF factor", we are the owners of the house and consequently, we listen to music as good men should do.
😉😀
Well then you've never heard an excellent speaker who has a FR as close to "flat" outdoors ......
How is it not desirable ?
WTF ?
Last edited:
Oh get off it with that "offensive" crap already.
The masses are tired of hearing such blabber.
Or don't you read the news?
Its quite amazing what sound some people will put up with.
I ran a mono mobile disco for 40 years and no one ever commented it wasnt stereo.
In the first few years before I got a mixer the speakers only worked up to 3KHz.
Again no complaints.
Never mind the quality, feel the noise.
I ran a mono mobile disco for 40 years and no one ever commented it wasnt stereo.
In the first few years before I got a mixer the speakers only worked up to 3KHz.
Again no complaints.
Never mind the quality, feel the noise.