Practice, Mate - practice!
Thanks - there were other incidents. (E.g. I regularly include a loudness feature on my volume controls - but rather more than only the center-tap single RC-version - but do not mention it. The sound is a winner every time but nobody is aware of its presence. 🙂)
Thanks - there were other incidents. (E.g. I regularly include a loudness feature on my volume controls - but rather more than only the center-tap single RC-version - but do not mention it. The sound is a winner every time but nobody is aware of its presence. 🙂)
Since you want to adjustments to old recordings, you are one of very few people who need a tone control.
The rest need to focus on why their amplifier (and speakers) needs frequency compensation to begin with.
Once you settle on a tone circuit, there are a few ways I'm sure you could bypass it.
Room compensation, different tone balance with different recordings, hearing idiosyncracies or getting older. And simple, before one goes to more elaborate digital systems and such.
I have already chirped in - my question is "why not?" Fine, if necessary to 'add-on' often over-expensive for what is obtained.
I am not accusing you of urban legend beliefs, Pennypacker, but I wish I know of a way to lay this one to rest generally. I have built such into my amplifiers ever since I began, use my own every now and then, and was never positively asked not to include them.
But not to make a mission out of this here, simply stating. (Most has already been said.)
This is fine.
Essentially you want to add sound-effects to subjectively overcome shortcomings your system and environment.
I disagree with the approach of tone compensation of different recordings. Compensation assumes you have a better benchmark to strive for. Unfortunately the original recording is the benchmark.
I won't even touch room compensation as specifics of rooms are way to variable to attempt to solve with a turn of a single dial.
Speakers are also extremely variable in nature, a different set with some brighter tweeters may eliminate the need for EQ in your case.
What you are doing is fine of course if you enjoy it, myself am a form follows function kind of person.
FWIW, many have found that a tilt-type tone control, rather than the Baxandall characteristic, provides a better means of taming recordings. Here's the circuit I built and tested, with the tilt portion cheerfully stolen from the excellent Quad preamp and adapted for tubes. If memory serves, Crown used something similar in its preamps as well.
SY,
Any response curves on this tilt control you built? I have a Quad 44 with the Tilt controls and love it. Just a bit goes a long way...
Any response curves on this tilt control you built? I have a Quad 44 with the Tilt controls and love it. Just a bit goes a long way...
Looks just like the Quad (since that's the circuit I "appropriated"). The key is the high open loop gain of the high gm pentode, which helps conformance to the curves set by the tone network.
H.E.Pennypacker,
Fair enough. Not to nit-pick, but the 'original' is still subject to someone's final judgment. I use my tone controls more often with LPs of which I have a few hundred spanning decades, perhaps variable responses lie there. Nevertheless, one can just as well leave them in zero position, which in my case is straight-line response, amplitude and phase-wise.
You are also correct regarding external effects on tone balance. Again I find no disadvantage from tone controls, and some possible freedom in having them.
Still, no quibble with your view-point; I can respect that. Concert hall seats are not equal response things anyway.
Fair enough. Not to nit-pick, but the 'original' is still subject to someone's final judgment. I use my tone controls more often with LPs of which I have a few hundred spanning decades, perhaps variable responses lie there. Nevertheless, one can just as well leave them in zero position, which in my case is straight-line response, amplitude and phase-wise.
You are also correct regarding external effects on tone balance. Again I find no disadvantage from tone controls, and some possible freedom in having them.
Still, no quibble with your view-point; I can respect that. Concert hall seats are not equal response things anyway.
You are assuming far too much about this topic. I am also a form follows function type of person, and tone controls have nothing to do with the supposed shortcoming of a system. The purpose is to help adjust for the deficiency in the mastering of the recordings, as per the end listener's taste. Regardless of how good the reproduction gear is, on its own it cannot make a thin or bright recording flatter. The tone controls work to help overcome the mastering's shortcomings. Sometimes all the music needs is a few decibels of adjustment to improve listener enjoyment. I find I prefer more bass than treble, and I dislike tilt controls because of the Ffect outside the bandwidth I desire to be altered. The key it to tune the controls to what you need most often.
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Having options is good right? I mean if you have a recording that isn't mastered to my liking (I have a vast collection of live recordings and tone controls are essential to dial in my specific taste in tonal balance) then tone controls are the way to go and they are not making up for any shortcomings in the amplifier.
Then just flip the tone bypass switch for a faithful reproduction of the recordings that have been mastered to your ears liking, best of both worlds right?
I will use led zeppelin for example, I love the Barry Diament mastered stuff much better than the latter re-mastered releases. This is my opinion and might differ from what other peoples ears tell them. For these I tend to hit the little button on my Mcintosh C2200 labeled "tone bypass". But to be honest the majority of the time I leave the tone controls on with the bass boosted a bit so I am in the same camp as koulky in that I like a bit more bottom end.
Then just flip the tone bypass switch for a faithful reproduction of the recordings that have been mastered to your ears liking, best of both worlds right?
I will use led zeppelin for example, I love the Barry Diament mastered stuff much better than the latter re-mastered releases. This is my opinion and might differ from what other peoples ears tell them. For these I tend to hit the little button on my Mcintosh C2200 labeled "tone bypass". But to be honest the majority of the time I leave the tone controls on with the bass boosted a bit so I am in the same camp as koulky in that I like a bit more bottom end.
Yep I agree. Its no different from using a hearing aid for hi roll-off correction due to normal aging.
For many people, it is the complete opposite. They want to be able to turn the treble down to make it more relaxed sounding. More commonly, the occasion arises where the listener may desire to give their music a little more bass. The biggest complaint regarding newer mastered albums, is centered around the bright & edgy sound.
Denny9167, if you were building this first circuit that you posted, you can bypass the 500k bass pot with a small capacitor in the 0.0022uF range to modify the Q factor of the bass control. The .001uF and .01uF bass circuit capacitors can be varied to modify how high the bass control carries into the midrange. Incremental increases in those value will move the boot to a lower frequency. Between the bass and midrange portions of the tone control circuit, you should perhaps place a 1k resistor.
Myself, I would use 1k Ohms between the bass and treble halves of the tone control circuit, and I would swap the 0.001uF and .01uF caps for 0.0033uF and 0.033uF, and I would bypass the strap the upper and lower half of the pot together with .022uF, and change the 2.2k Ohms lower leg resistor to 20k. The phase shift at 20Hz is about 55 degrees, but if you increase the 0.1uF cap that is leading to the tone controls to 1uF, and change the two 0.47uF caps to 4.7uF and the output cap to 4.7uF, the phase shift drops to 17 degrees. The response at flat is then +1/-0dB from 10Hz to 20kHz with 0.5dB suck-out at 500Hz. In theory, this is much better than theirs. Phase shift at 20kHz is just under 8 degrees, that may be correctable, too.
Myself, I would use 1k Ohms between the bass and treble halves of the tone control circuit, and I would swap the 0.001uF and .01uF caps for 0.0033uF and 0.033uF, and I would bypass the strap the upper and lower half of the pot together with .022uF, and change the 2.2k Ohms lower leg resistor to 20k. The phase shift at 20Hz is about 55 degrees, but if you increase the 0.1uF cap that is leading to the tone controls to 1uF, and change the two 0.47uF caps to 4.7uF and the output cap to 4.7uF, the phase shift drops to 17 degrees. The response at flat is then +1/-0dB from 10Hz to 20kHz with 0.5dB suck-out at 500Hz. In theory, this is much better than theirs. Phase shift at 20kHz is just under 8 degrees, that may be correctable, too.
I just used a ceramic trimmer that I repurposed from an old oscilloscope. It's pretty noncritical, the adjustment is just for feedback compensation to prevent any ringing or overshoot on square waves.
Jameshillj, below is how I modified design. The top response curve is with the tone controls flat, as per audio taper potentiometers with their center point being 10% the total value. I represent this with a 450k and 50k pair of resistors. The bottom curve is with the bass turned up a bit. There is a 1.25dB dip for more than 5dB of boost enhancement. While this is only theory, the design is now better than some commercial preamp's tone controls. Here is what I did to the interstage circuitry:
An externally hosted image should be here but it was not working when we last tested it.
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