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We aren't talking the kind of tone controls from 30 yrs. ago. Build it Roger, along with a balance control. Some day most everyone will need one and it's no fun trying to find a preamp/DAC with one that meets your needs.
Tone controls are a hot topic and I thank fastfred for bringing it up. I currently have one tone control in my system that I find very useful and to my knowledge a control like this has never been offered. It is a flat shelf from 80 Hz down with a very steep (24 db/octave) low pass cutoff at 80 Hz. This allows me to control the bass up and down several dB without affecting anything else. The main thing I am concerned with is male vocals and lower mid-range instruments that get very thick and muddy when boosted. You don't want to boost Leon Redbone's voice above 80 Hz. This frequency could be a bit higher or lower however, it is not easily switch selected nor is the exact frequency that important. Add to that a gentle treble control whose hinge point could easily be switch selected at 1,2,4,6,8,10 KHz. Boost and cut would be at a 6 dB/octave rate. Since there is only one capacitor in this passive control it is easily switch selected. These choices are made from entirely new information I have gathered in my own research and have not been implemented before. Standard bass and treble controls are nothing like this and in comparison are rather poor solutions. They do muddy up sound and well deserve their bad reputation in high end audio as do equalizers. The problem with EQs are the number of parts and signal paths encountered. By their very nature they are resonators. They are generally implemented with an great number of ICs. There is one IC for each slider in a graphic EQ and several for each filter in a parametric. In addition there are IC input and output buffers and lots of slider pots in the signal path. For people who can barely trust one volume control, how can they even consider those.Without disclosing too much of my circuitry I will say that the main signal can be handled entirely passively and only the frequencies below 80 Hz need be acted on actively. Therefore we will not add any active circuitry or potentiometers in the midrange. All the tone controlling is done in a side chain where the midrange is unaffected. The unit can be built with one tube of gain and become your line preamp or it can have a slight loss as many systems already have too much gain.Here are a few references to pitch frequencies http://www.seventhstring.com/resources/notefrequencies.htmlhttp://en.wikipedia.org/wiki/Bass_(voice_type)
Is this "tone control" similar to what you have in the crossover you provide with your subwoofer? I am very pleased with mine, although I rarely change the bass by more than 2 db or so. The midrange, includingbaritone voice (eg. Dietrich-Fischer-Dieskau) is unaffected. On the other hand, several people are quite excited about something more elaborate: DSP units that allow one to flatten peaks in the bass due to room effects. People with subwoofers could conceivably use theseafter the low pass filter and thus avoid affecting the upper frequencies (although some reviewers are claiming the DSP could improve these frequencies as well). It is true that room effects can have a big effect on the bass:I've heard the same band sound quite different in different venues. So I'm not convinced that getting rid of the effect of one's own room is so important. Thoughts?
Yes, this is based on my use of the crossover system you have with the addition of a treble control. I think that people in our (tube) camp are not interested in putting a DSP in their system. I certainly am not. For all the work we do to have a simple signal path that would really throw a monkey-wrench in the system. I am wary of fixing room problems in that way as they require putting a microphone somewhere and letting the system flatten itself. Then you move the microphone (or yourself) and the problem is somewhere else. I just think we don't need that kind of thing going on. In my opinion good sound comes from simple signal paths and simple speakers with good physics. All that other stuff just clouds the issue and the sound. What fastfred and I are proposing is something that allows the listener to adjust two things that vary greatly with listening level. Those being the perception of bass and treble at low levels and our desire for more or less as per the recording. There are some recordings that just have too much or too little bass. Should we suffer for the bad taste of some recording engineers? I have some CDs that are absolutely unplayable unless I reduce the bass because the recording engineer did something stupid. An example that comes to mind is Emmylou Harris Wrecking Ball. For those who are unfamiliar with how the ear responds at different volume levels here are the Fletcher-Munson curves. http://en.wikipedia.org/wiki/Fletcher%E2%80%93Munson_curveshttp://en.wikipedia.org/wiki/Equal-loudness_contours
do we need tone controls? why are they needed in the first place? lets see maybe ones speakers are of poor design or maybe their electronics are poor also. a band aid solution to equipment that maybe lacking in certain areas.
do we need tone controls? why are they needed in the first place? lets see maybe ones speakers are of poor design or maybe their electronics are poor also. a band aid solution to equipment that maybe lacking in certain areas.these are certain things to ponder about.
How would you used it/hook it up?What kind of control would you have?
One thing is sure, audiophiles hate tone controls and music lovers like them, mainly for listen with cheap speakers.