How exactly does treble control work?

[bjornb17]

Yeah yeah i know its a very simple question that i should probably know the answer to, but i dont :P I know it increases the treble of the speaker (duh), but how exactly does it go about doing this?

Does increasing trebble just raise the high-frequency volume, or does it do something else?

[GMichael]

Yeah yeah i know its a very simple question that i should probably know the answer to, but i dont :P I know it increases the treble of the speaker (duh), but how exactly does it go about doing this?

Does increasing trebble just raise the high-frequency volume, or does it do something else?

It will also send out X-mas cards to every member of your family. This is it's number one use.

Oops, sorry. Couldn't hold that back.

I'm not sure how it increases your treble. I know it has a variable resistor in it.

[kexodusc]

Hmmm, good question...never really thought about it before.
I'm guessing it's similar to some guitars I've built. Your tone controls aren't actually boosting frequency bands (well, unless they're digital, but lets stick to analog), but rather applying different levels of cut. Similar to a speakers crossover, a properly calculated pot will use capacitors and inductors, and variable resistors to apply different levels of cut.

With capacitors for example, their resistance changes with frequency. At low frequency, the impedance is very high, at high frequency the impedance is low...so your applying different levels of resistance to the signal as you increase the control.

Short, non EE explanation. Hope I'm at least somewhat right.

[Resident Loser]

Yeah yeah i know its a very simple question that i should probably know the answer to, but i dont :P I know it increases the treble of the speaker (duh), but how exactly does it go about doing this?

Does increasing trebble just raise the high-frequency volume, or does it do something else?

...most speaker treble controls are simply a "cut" filter...even though your control may say +6dB at max, it doesn't amplifiy anything. At max, the signal goes through unfettered, from that point through the mfr's. arbitrary 0dB point down to it's -6db lower level, it simply adds resistance...generally speaking of course...

Of course, this refers to non-active loudspeakers powered by an outboard amp...

jimHJJ(...Merry Christmas to all...)

[markw]

No, it does not increase treble. A speaker, being a passive device has no way to "increase" treble from the amp. It can only cut it.

Now, the designer of the speaker may have designed it so that when it's in the middle of it's range it would provide what he feels is the most balanced sound. That way, you might be able to turn it all the way up or down to increase or decrease the apparant treble. It's still not "adding" to it.

As to the electronics, I'll suggest you check out some books. It has to deal with resistors, capacitors and the like. First or second analog year AC circuits should cover it.

And, as far as amps go, yes they CAN boost the treble and bass. Remember, they are not passive devices and have gain, which can be applied selectively.

[bjornb17]

No, it does not increase treble. A speaker, being a passive device has no way to "increase" treble from the amp. It can only cut it.

Now, the designer of the speaker may have designed it so that when it's in the middle of it's range it would provide what he feels is the most balanced sound. That way, you might be able to turn it all the way up or down to increase or decrease the apparant treble. It's still not "adding" to it.

As to the electronics, I'll suggest you check out some books. It has to deal with resistors, capacitors and the like. First or second analog year AC circuits should cover it.

And, as far as amps go, yes they CAN boost the treble and bass. Remember, they are not passive devices and have gain, which can be applied selectively.

Thanks for the input. I was actually referring to the treble control on the receiver. I guess i didnt mention that

[Florian]

Tone Controls

Generally the use of tone controls, we hope, will be unnecessary. Most quality speakers have been designed to deliver a flat frequency response and a well balanced sound reproduction. However, in some listening environments this balance may be distorted by room effects. Tone controls in this case can then be used to compensate for these problems.

If you do need to turn the tone controls up, whether it is for room acoustics or personal taste, then it is worth noting the effect as far as output power and 'clipping' is concerned.

Bass and treble controls adjust the level of a selected range of frequencies in addition to the volume control which adjusts the level at all frequencies. If an amplifier is already being driven at full power and the bass and treble is then turned up, the result is 'clipping' and likely failure of the speakers.

[Woochifer]

At the preamp level, I'm pretty sure that the treble controls will boost the signal. Part of the rationale behind the high end market's evolution into the current "thou shalt use no tone controls" edict that most self-described audiophiles follow is the belief that tone controls that add treble or bass also add distortion and raise the noise floor.

Same thing goes for loudness switches, which can add noise to the signal (then again, their intended use is only during low level listening to compensate for our reduced hearing sensitivity with high and low frequencies at lower levels). This is the reason why on its two-channel amps Yamaha goes with a variable loudness contour rather than a signal boosting loudness switch -- because a variable loudness contour works by reducing the overall signal and while leaving the low and highs at an elevated level (raising the volume will raise the overall level and have the net effect of boosting the highs and lows without added noise).

As others have pointed out, the level control pots that are found on some speakers have no way of applying any gain to the signal, so they would work by attenuating the incoming signal.

[E-Stat]

the belief that tone controls that add treble or bass also add distortion and raise the noise floor.

Do you know of a perfect active gain stage?

rw

[Woochifer]

Do you know of a perfect active gain stage?

No. Do you know of a perfect speaker or room acoustical condition?

[E-Stat]

No. Do you know of a perfect speaker or room acoustical condition?

I'm glad we agree upon what transcends "belief". I know of no perfect audio device.

rw

[shokhead]

So where do you guys have your controls at? Mine are +2 on bass and -2 on treble.

[GMichael]

So, it won't send out my cards? Ut oh. Uhm, I may be a little busy this weekend.

[StanleyMuso]

Of course, in a perfect world, with perfect recordings, tone controls should not be needed. My current system has no tone controls, but sometimes I miss them. My recorded materials are not all perfect. Some are very old, but not replaceable. Some of them are rare and have never been re-issued. There is a lot of background hiss or other distortion. The use of tone controls can make such sources more pleasant to listen to. I'm sorry, but I am not going to subscribe to some self imposed purist nonsense and throw out old but treasured recordings just because they do not conform to some idiot's idea of perfections. They may not be technically perfect, but some of them are artistically perfect. Sooner or later, I WILL re-introduce some form of tone cotrol just for the times when I want to listen to my treasured old recordings in order to cut out some extrenuous noise.

[Florian]

It mostly comes down to personal choice. You either choose to the most accurate reproduction of whats on the source or you favor a altered sound to your liking. The editor of that article is correct that you can use it for room correction purposes. But by cutting down the treble or bass it also removes micro information in that area. Now, we know that most systems out there that are affordable will not reveal that information in the first place but i personally prefer the hiss and crackles and get a acurate reproduction then a sound i personally prefer.

Its all about choice

[StanleyMuso]

It mostly comes down to personal choice. You either choose to the most accurate reproduction of whats on the source or you favor a altered sound to your liking. The editor of that article is correct that you can use it for room correction purposes. But by cutting down the treble or bass it also removes micro information in that area. Now, we know that most systems out there that are affordable will not reveal that information in the first place but i personally prefer the hiss and crackles and get a acurate reproduction then a sound i personally prefer.

Its all about choice

rigid a position. I have some recordings which are so old and so worn out that the only way you can retrieve the musical information is by cutting out the background noise. One of these days when I have more time I will record them digitally and clean them up a bit, but until then, the only way you can even hear the music is by using tone controls. Well, not for the moment. My current set up won't let me do it.

[Florian]

I can recommend a machiene that will flatten the records again if your interested.

[Bernd]

rigid a position. I have some recordings which are so old and so worn out that the only way you can retrieve the musical information is by cutting out the background noise. One of these days when I have more time I will record them digitally and clean them up a bit, but until then, the only way you can even hear the music is by using tone controls. Well, not for the moment. My current set up won't let me do it.

Hi,

I am intrigued. How can tone controls help to retrieve information from a worn out record?
If the information can not be retrieved in the first place you can not add to it later. On top of that any additional artifact in the reproduction chain will have an effect on the original intended sound. Like Flo said It's all down to choice. I like to hear the music how it was meant to be.

Peace

Bernd