Frequently Asked Questions about The Delicious One
(feel free to submit additional questions to info@deliciousdecibels.com).
What does The Delicious One actually do?
As you turn the Deliciousness Control knob clockwise from the full counter-clockwise position (making sure that you are not in bypass mode), the tonality (frequency response) gradually changes from flat to a curve that gently and gradually trims carefully selected and empirically tested midrange and treble frequencies. The figure below (an actual measurement of The Delicious One in action) shows what those curves look like as you rotate the knob from the full counter-clockwise (flat) to full clockwise (maximum effect) in steps of 30 degrees.
(feel free to submit additional questions to info@deliciousdecibels.com).
What does The Delicious One actually do?
As you turn the Deliciousness Control knob clockwise from the full counter-clockwise position (making sure that you are not in bypass mode), the tonality (frequency response) gradually changes from flat to a curve that gently and gradually trims carefully selected and empirically tested midrange and treble frequencies. The figure below (an actual measurement of The Delicious One in action) shows what those curves look like as you rotate the knob from the full counter-clockwise (flat) to full clockwise (maximum effect) in steps of 30 degrees.
As you can see, the amount of effect applied is very gradual at first (since most recordings need minimal correction) and more pronounced toward the end. But even at the bottom end of the range the control (the clockwise-most positions) thanks to the large knob, you can easily fine tune the amount of effect to any intermediate curve in between those we plotted.
How does that change in the frequency response make the music more delicious? What’s going on?
In the case of thin-sounding recording, the boost in the bass relative to the midrange and, to a lesser extent, the top frequencies, makes the recording sound richer and more satisfying. See top-most curves in graph.
Similarly, in the case of harsh, fatiguing, over-compressed recordings, by gently de-emphasizing the midrange (the frequencies to which we are most sensitive and become most annoying with poor recordings) the music becomes less edgy and “in your face.” See middle curves in graph.
Finally, in the case of low-volume listening, The Delicious One operates like a more traditional loudness control by de-emphasizing the mids more aggressively but also taking off quite a bit from the high frequencies. See bottom curves in the graph.
By looking at the curve above it looks as if the overall volume is also reduced by a few decibels when the effect is applied. Why is that?
After experimenting with several circuit options, we decided to make The Delicious One a passive device (more about that next). Passive filters and controls offer several advantages compared to active filters but they do reduce the overall audio level. As we’ll see, however, this is actually an advantage for this particular application.
What’s the difference between an active and passive filter, and why did you decide against an active filter?
An active audio filter requires one or more amplifiers and/or buffers to compensate for the loss of decibels in audio level caused by the filtering components. Providing such amplification adds significantly to the cost, complication and side-effects: more components for the signal to go through, power supply, power cords, etc. In many cases, these drawbacks are well justified and there’s no choice. However, in this particular case–especially for loudness control–the reduction in overall audio level actually turns out to be an advantage; it means that the volume knob on your preamp or amp can be turned more toward the middle of the range as opposed to the lowest setting where many volume controls are not very sensitive or track very well.
It does not look like you followed either the Fletcher-Munson or the ISO equal-loudness curves in designing and tuning your circuit’s effect. Why?
At first, we experimented with designs that took into account and compensated for several published equal-loudness curves ... and we really disliked the results. We puzzled about this a bit and quickly came to the following conclusion: Those experimental results were obtained by using sequences of pure test tones (e.g. 32Hz ... 64Hz ... 1,000Hz ... 4,000Hz) played one at a time through headphone and/or in sound-proof booths in a laboratory. They revealed a general pattern of frequency and volume-related sensitivity, but those results are not necessarily applicable to the playing and enjoyment of real music, which presents to the ears not a single pure tone at a time but a far more complex waveform with a full spectrum of dozens if not hundreds of main frequencies and harmonics. For example, if we went strictly by the Fletcher-Munson or ISO curves, we’d provide very minimal compensation for high frequencies. But when we tested such a circuit we found the results very unsatisfying. The music lost all sense of air and breath; it sounded muddy and confined. Furthermore, the environmental and physical conditions for those experiments (sound-proof booths and/or headphones) combined with psychological conditions of the subjects (intently focused on hearing faint tones, and probably a bit stressed and anxious) cannot be compared to a person trying to enjoy music in their living room with natural ambient sounds and a relaxing glass of wine in their hand. In the end, we trusted our ears, and those of our audiophile friends and testers and settled on the design and frequency response curves that gave us the greatest sonic pleasure.
Having said that, we’ve designed The Delicious One so that the most extreme clockwise position on the Deliciousness Control (the bottom curve on the graph above) approximates what a by-the-book (as opposed to by-the-ears) loudness compensation suggests. Sounds pretty muddy and lifeless, doesn’t it? We can’t imagine many situation or recordings that would call for so extreme an adjustment, but it’s there if you really want it.
You said that The Delicious One is more than just a loudness control; can you expand on that?
We have admit that this was more a fortuitous discovery than an original intention on our part. The original objective for The Delicious One was to provide an outboard, by-passable, high-quality, variable loudness control. But, as we experimented with various circuits and components, we discovered that some of them made a lot of recordings sound better and more pleasurable regardless of the volume at which we played them; and they proved particularly effective on some recordings that we found to be harsh and fatiguing.
We set out to investigate–to try to explain what was going on with our ears and brain. The tentative conclusion we reached (at least with respect to certain over-compressed or particularly harsh recordings) is the following: Because our hearing is most sensitive to the mid-range frequencies (as discussed above), by taming those frequencies a bit with respect to the bass and treble/upper-treble helps certain recordings sound fuller, less harsh and less fatiguing. Because your system, your music, your ears and your tastes may be different from ours, you may not get the same results, but we find ourselves using The Delicious One as much more than just a variable loudness control.
Thanks to The Delicious One, a number of records that we didn’t listen to because they sounded thin or harsh are back in regular playing rotation. Yay!
If I start with the Deliciousness Control is set all the way counter-clockwise, nothing much seems to happen until I’ve turned it clockwise quite a bit. What’s going on?
The circuit is designed to start off flat, progress very gently at first and more decisively toward the end of the rotation (see previous graph.) Starting from the full counter-clockwise (no effect) position, the first 30-60 degrees of counter-clockwise rotation of the Deliciousness Control have an effect of just a few decibels which, depending on the music being played, the volume, your hearing and other variables, you may not be able to detect. Studies show that most people have a hard time in reliably hearing differences of less than 2 to 3 decibels.
What’s with the big knob and horizontal design? Why doesn’t The Delicious One look more like a normal audio component with a vertical front panel and normal-sized knobs?
We started with a traditional design, but we also experimented with new ideas. After playing around with several types of enclosures and knobs, we discovered that the big knob with a horizontal orientation was the most natural and satisfying to use for this application. The large diameter of the knob, in particular, makes it easy to apply just the right level of effect. All early testers loved it; we loved it; and so we went with that. If you really can’t stand or can’t use such a design, we might be able to provide you with a custom enclosure.
Speaking of knob rotation, since aren’t there any labels or markings on the enclosure? How the heck am I supposed to know exactly how much Deliciousness I am applying?
Deliciousness is subjective and the amount required will vary depending on the listening situation, recording and even mood. Putting a visual “scale” on The Delicious One seemed silly. We believe that the best way to use it is to use your ears and not your eyes. Put on the music you want to listen to, set the overall volume, then (with optional, but recommended, eyes closed) turn the Deliciousness Control knob back and forth until you zero-in on the position that sounds best for that particular piece of music or listening situation. The position of black dot on the knob gives you a rough indication of how much effect you are applying. Note: If you ever need to readjust or tighten the big Deliciousness Knob, remove the black dot (your fingernails should do) and insert a 2mm allen wrench in the hole to tighten or loosen the holding screw as needed.
How does that change in the frequency response make the music more delicious? What’s going on?
In the case of thin-sounding recording, the boost in the bass relative to the midrange and, to a lesser extent, the top frequencies, makes the recording sound richer and more satisfying. See top-most curves in graph.
Similarly, in the case of harsh, fatiguing, over-compressed recordings, by gently de-emphasizing the midrange (the frequencies to which we are most sensitive and become most annoying with poor recordings) the music becomes less edgy and “in your face.” See middle curves in graph.
Finally, in the case of low-volume listening, The Delicious One operates like a more traditional loudness control by de-emphasizing the mids more aggressively but also taking off quite a bit from the high frequencies. See bottom curves in the graph.
By looking at the curve above it looks as if the overall volume is also reduced by a few decibels when the effect is applied. Why is that?
After experimenting with several circuit options, we decided to make The Delicious One a passive device (more about that next). Passive filters and controls offer several advantages compared to active filters but they do reduce the overall audio level. As we’ll see, however, this is actually an advantage for this particular application.
What’s the difference between an active and passive filter, and why did you decide against an active filter?
An active audio filter requires one or more amplifiers and/or buffers to compensate for the loss of decibels in audio level caused by the filtering components. Providing such amplification adds significantly to the cost, complication and side-effects: more components for the signal to go through, power supply, power cords, etc. In many cases, these drawbacks are well justified and there’s no choice. However, in this particular case–especially for loudness control–the reduction in overall audio level actually turns out to be an advantage; it means that the volume knob on your preamp or amp can be turned more toward the middle of the range as opposed to the lowest setting where many volume controls are not very sensitive or track very well.
It does not look like you followed either the Fletcher-Munson or the ISO equal-loudness curves in designing and tuning your circuit’s effect. Why?
At first, we experimented with designs that took into account and compensated for several published equal-loudness curves ... and we really disliked the results. We puzzled about this a bit and quickly came to the following conclusion: Those experimental results were obtained by using sequences of pure test tones (e.g. 32Hz ... 64Hz ... 1,000Hz ... 4,000Hz) played one at a time through headphone and/or in sound-proof booths in a laboratory. They revealed a general pattern of frequency and volume-related sensitivity, but those results are not necessarily applicable to the playing and enjoyment of real music, which presents to the ears not a single pure tone at a time but a far more complex waveform with a full spectrum of dozens if not hundreds of main frequencies and harmonics. For example, if we went strictly by the Fletcher-Munson or ISO curves, we’d provide very minimal compensation for high frequencies. But when we tested such a circuit we found the results very unsatisfying. The music lost all sense of air and breath; it sounded muddy and confined. Furthermore, the environmental and physical conditions for those experiments (sound-proof booths and/or headphones) combined with psychological conditions of the subjects (intently focused on hearing faint tones, and probably a bit stressed and anxious) cannot be compared to a person trying to enjoy music in their living room with natural ambient sounds and a relaxing glass of wine in their hand. In the end, we trusted our ears, and those of our audiophile friends and testers and settled on the design and frequency response curves that gave us the greatest sonic pleasure.
Having said that, we’ve designed The Delicious One so that the most extreme clockwise position on the Deliciousness Control (the bottom curve on the graph above) approximates what a by-the-book (as opposed to by-the-ears) loudness compensation suggests. Sounds pretty muddy and lifeless, doesn’t it? We can’t imagine many situation or recordings that would call for so extreme an adjustment, but it’s there if you really want it.
You said that The Delicious One is more than just a loudness control; can you expand on that?
We have admit that this was more a fortuitous discovery than an original intention on our part. The original objective for The Delicious One was to provide an outboard, by-passable, high-quality, variable loudness control. But, as we experimented with various circuits and components, we discovered that some of them made a lot of recordings sound better and more pleasurable regardless of the volume at which we played them; and they proved particularly effective on some recordings that we found to be harsh and fatiguing.
We set out to investigate–to try to explain what was going on with our ears and brain. The tentative conclusion we reached (at least with respect to certain over-compressed or particularly harsh recordings) is the following: Because our hearing is most sensitive to the mid-range frequencies (as discussed above), by taming those frequencies a bit with respect to the bass and treble/upper-treble helps certain recordings sound fuller, less harsh and less fatiguing. Because your system, your music, your ears and your tastes may be different from ours, you may not get the same results, but we find ourselves using The Delicious One as much more than just a variable loudness control.
Thanks to The Delicious One, a number of records that we didn’t listen to because they sounded thin or harsh are back in regular playing rotation. Yay!
If I start with the Deliciousness Control is set all the way counter-clockwise, nothing much seems to happen until I’ve turned it clockwise quite a bit. What’s going on?
The circuit is designed to start off flat, progress very gently at first and more decisively toward the end of the rotation (see previous graph.) Starting from the full counter-clockwise (no effect) position, the first 30-60 degrees of counter-clockwise rotation of the Deliciousness Control have an effect of just a few decibels which, depending on the music being played, the volume, your hearing and other variables, you may not be able to detect. Studies show that most people have a hard time in reliably hearing differences of less than 2 to 3 decibels.
What’s with the big knob and horizontal design? Why doesn’t The Delicious One look more like a normal audio component with a vertical front panel and normal-sized knobs?
We started with a traditional design, but we also experimented with new ideas. After playing around with several types of enclosures and knobs, we discovered that the big knob with a horizontal orientation was the most natural and satisfying to use for this application. The large diameter of the knob, in particular, makes it easy to apply just the right level of effect. All early testers loved it; we loved it; and so we went with that. If you really can’t stand or can’t use such a design, we might be able to provide you with a custom enclosure.
Speaking of knob rotation, since aren’t there any labels or markings on the enclosure? How the heck am I supposed to know exactly how much Deliciousness I am applying?
Deliciousness is subjective and the amount required will vary depending on the listening situation, recording and even mood. Putting a visual “scale” on The Delicious One seemed silly. We believe that the best way to use it is to use your ears and not your eyes. Put on the music you want to listen to, set the overall volume, then (with optional, but recommended, eyes closed) turn the Deliciousness Control knob back and forth until you zero-in on the position that sounds best for that particular piece of music or listening situation. The position of black dot on the knob gives you a rough indication of how much effect you are applying. Note: If you ever need to readjust or tighten the big Deliciousness Knob, remove the black dot (your fingernails should do) and insert a 2mm allen wrench in the hole to tighten or loosen the holding screw as needed.