Disc blues recorded live at the Music Hall of St. John Block Lupatoto
Dario Ferronato: guitar, harmonica and vocals
Federico Fuggin: piano and keyboards
Daniele Danish: low
Sandro Avesani : baritone sax
Michele Pisa: battery
Saturday, October 27, 2007
Thursday, October 18, 2007
Can U Get Braces With Gum Disease
Audio / DIY / Speakers / QNPS-2 - Design: crossover
The "philosophy" NPS would require an infinite number of ways, each connected to the cluster of speakers of different geometry.
addition to the problems of cost, complexity, et c., there are actually several practical limitations.
First of all, above 5 KHz wavelengths are hardly "representative", however, with transducers that have dimensions several centimeters.
Secondly, at low frequencies, the wavelengths become enormous, but not insignificant in terms of NPS (it is very difficult to "locate" a source at these frequencies).
is also good practice to make the streets so as to cover at least two octaves, this is to simplify the management of the crossings, both to try to limit the emission of harmonics of the same key from different transducers (a problem also inherent to the diffuser multi-way).
Taking this into account, the maximum would produce a five-way with the following frequencies: 80, 320, 1k25, 5k, corresponding to the wavelength "core" of 8.5 m, 2.1, 0.51 , 0.13, 0034. With
frequencies so close you should definitely play a bit with the cutting slopes.
One possibility would be to adopt a Rane AC 23B, which allows five-way mono, and various slopes. 
The "philosophy" NPS would require an infinite number of ways, each connected to the cluster of speakers of different geometry.
addition to the problems of cost, complexity, et c., there are actually several practical limitations.
First of all, above 5 KHz wavelengths are hardly "representative", however, with transducers that have dimensions several centimeters.
Secondly, at low frequencies, the wavelengths become enormous, but not insignificant in terms of NPS (it is very difficult to "locate" a source at these frequencies).
is also good practice to make the streets so as to cover at least two octaves, this is to simplify the management of the crossings, both to try to limit the emission of harmonics of the same key from different transducers (a problem also inherent to the diffuser multi-way).
Taking this into account, the maximum would produce a five-way with the following frequencies: 80, 320, 1k25, 5k, corresponding to the wavelength "core" of 8.5 m, 2.1, 0.51 , 0.13, 0034. With
frequencies so close you should definitely play a bit with the cutting slopes.
One possibility would be to adopt a Rane AC 23B, which allows five-way mono, and various slopes.
Why Does My Dog's Prostate Swell
Audio / DIY / Speakers / QNPS-2 - The project: structure and geometry
The structure is conditioned by:
- the "needs" of the various transducers in terms of a dipole panel
- NPS geometry, where feasible
- the shape of the panel to minimize risonnaze, diffraction et c.
- Tweeter: given the projected range, whatever the shape of the panel, this would be "seen" by the transducer as a virtually infinite level (relative to the wavelength). Potential effects of diffraction concern insignificant fraction of signal due to the high directivity, I do not think there are particular effects on the overall geometry, apart from the usual adroitness pairing "flat" to the panel.
- mid-high: that is what we saw for the tweeter, subject to any care to a minimum of fitting on the edges of the panels. Given the wavelengths involved siorienterebbe us to a single transducer, ideally, a ribbon of about 10 cm.
- mid-range, the expected distance (two feet) does not present any particular restrictions on the structure. Are probably still present diffraction effects: wanting them to consider the lowest frequency (320 Hz), should be rounded ends with a radius of at least 1 / 8 of a wavelength that is longer than 10 cm!
This is probably the most critical project.
-woofer: cutting back on a regular five-way speakers should cover from 80 to 320 Hz, with a distance of about 2.1 m. The problem is that a dipole classic (albeit with wings) would be very bulky in width to 80 Hz (about 1.3 m) and then you should use some variant of H-frame.
An interesting alternative would be to exploit the presence of the sub-woofer to limit the bandwidth to about 160 Hz, the frequency at which you could still make a dipole efficiently without extra unsightly structures. Nothing prevents naturally compensate instead the roll-off "brute force", especially considering the good results in this sense of QNPS-2.
The problem may be rather to allocate part of the band "voice" to the sub-woofer, with completely different shapes and colorings from the woofer. In addition, a band so important to one eighth compressed may cause the critical calibration. It may then be paying a corresponding "slip" up one eighth of all the higher cutoff frequencies.
Initial size of the panel for a cutoff frequency of 160 Hz, perhaps with a very steep slope, then reserving the right to lower it to the extent allowed by the DSP correction. All this would naturally strong
implications on the whole, would drop the assumption that the "cut-up" to about 1.5 m, freeing up space for the vertical sub-woofer, electronics and reducing the overall development required.
sub-woofer: common ground that would be a single cone, and that should be placed at the bottom (to qualify for the "reflection" of the floor) it would seem a more rational version of the "Ripoli. This would fix the speaker down by limiting the overall size and allowing the positioning of the woofer below.
From a structural standpoint is to realize the subwoofer as a base (perhaps independent) on which to mount the panel.
The geometry must be such as to the issue of frequencies up to 300 Hz in order to take account of "smearing" in the cross-over, and the possibility of having to use the loudspeaker above the frequency "sub" classic. 
The structure is conditioned by:
- the "needs" of the various transducers in terms of a dipole panel
- NPS geometry, where feasible
- the shape of the panel to minimize risonnaze, diffraction et c.
- Tweeter: given the projected range, whatever the shape of the panel, this would be "seen" by the transducer as a virtually infinite level (relative to the wavelength). Potential effects of diffraction concern insignificant fraction of signal due to the high directivity, I do not think there are particular effects on the overall geometry, apart from the usual adroitness pairing "flat" to the panel.
- mid-high: that is what we saw for the tweeter, subject to any care to a minimum of fitting on the edges of the panels. Given the wavelengths involved siorienterebbe us to a single transducer, ideally, a ribbon of about 10 cm.
- mid-range, the expected distance (two feet) does not present any particular restrictions on the structure. Are probably still present diffraction effects: wanting them to consider the lowest frequency (320 Hz), should be rounded ends with a radius of at least 1 / 8 of a wavelength that is longer than 10 cm!
This is probably the most critical project.
-woofer: cutting back on a regular five-way speakers should cover from 80 to 320 Hz, with a distance of about 2.1 m. The problem is that a dipole classic (albeit with wings) would be very bulky in width to 80 Hz (about 1.3 m) and then you should use some variant of H-frame.
An interesting alternative would be to exploit the presence of the sub-woofer to limit the bandwidth to about 160 Hz, the frequency at which you could still make a dipole efficiently without extra unsightly structures. Nothing prevents naturally compensate instead the roll-off "brute force", especially considering the good results in this sense of QNPS-2.
The problem may be rather to allocate part of the band "voice" to the sub-woofer, with completely different shapes and colorings from the woofer. In addition, a band so important to one eighth compressed may cause the critical calibration. It may then be paying a corresponding "slip" up one eighth of all the higher cutoff frequencies.
Initial size of the panel for a cutoff frequency of 160 Hz, perhaps with a very steep slope, then reserving the right to lower it to the extent allowed by the DSP correction. All this would naturally strong
implications on the whole, would drop the assumption that the "cut-up" to about 1.5 m, freeing up space for the vertical sub-woofer, electronics and reducing the overall development required.
sub-woofer: common ground that would be a single cone, and that should be placed at the bottom (to qualify for the "reflection" of the floor) it would seem a more rational version of the "Ripoli. This would fix the speaker down by limiting the overall size and allowing the positioning of the woofer below.
From a structural standpoint is to realize the subwoofer as a base (perhaps independent) on which to mount the panel.
The geometry must be such as to the issue of frequencies up to 300 Hz in order to take account of "smearing" in the cross-over, and the possibility of having to use the loudspeaker above the frequency "sub" classic.
Wednesday, October 3, 2007
Ikea Strande Lamp Bulbs
DONE IN CLASS SCHEDULE
............................... REASON ---> is an objective knowledge: it is
................................. .. incontrovertible
..
RIGHT ' ......... (IMAGE)
..
............................... MEANING -------> govern VIEWS
................................ .... and change according
.................................... period and subject 
............................... REASON ---> is an objective knowledge: it is
................................. .. incontrovertible
..
RIGHT ' ......... (IMAGE)
..
............................... MEANING -------> govern VIEWS
................................ .... and change according
.................................... period and subject
Symptoms Of A Nymphomaniac
Audio / DIY / Speakers / QNPS-2 - The project: transducers
The choice of the transducers is presented simplified compared to QNPS-1, because the way they barely cover two octaves each.
Tweeter: Having a successful outcome would confirm the BG Neo3PDR
Mid-High: A good match with the Neo3 is definitely the Neo8: same "tone" and very linear response range assumed (1K2 ~ 5K). In addition, the size of the transducer is the same size of the wavelengths involved. Mid
: the possibility for the midrange are many, given the rather low bandwidth request (315 ~ 1250). The alternatives are currently:
TB W4-1337S (an overkill at this point, if they are still available)
TB W4-639SE (4 ", 8 Ohm, 6 g)
Morel MW 114-S (4" 8 Ohm, 7g, Neodymium)
Woofer: Having failed to confirm the excellent Peerless SLS12
Sub: for divers could recover the initial idea for the woofers QNPS-1: The 385 Dayton IB 15 ". Even at these frequencies because the NPS does not make much sense, and then you could use only one speaker. In this case you should probably put a couple of bridgre mono, because unfortunately it is only available in 8 ohms., but if you want adopt a push pull "the Linkwitz" the 15 "would be a little too oversized, and as such powers would return to space and 12", perhaps with greater excursion (type Peerless XLS12) 
The choice of the transducers is presented simplified compared to QNPS-1, because the way they barely cover two octaves each.
Tweeter: Having a successful outcome would confirm the BG Neo3PDR
Mid-High: A good match with the Neo3 is definitely the Neo8: same "tone" and very linear response range assumed (1K2 ~ 5K). In addition, the size of the transducer is the same size of the wavelengths involved. Mid
: the possibility for the midrange are many, given the rather low bandwidth request (315 ~ 1250). The alternatives are currently:
TB W4-1337S (an overkill at this point, if they are still available)
TB W4-639SE (4 ", 8 Ohm, 6 g)
Morel MW 114-S (4" 8 Ohm, 7g, Neodymium)
Woofer: Having failed to confirm the excellent Peerless SLS12
Sub: for divers could recover the initial idea for the woofers QNPS-1: The 385 Dayton IB 15 ". Even at these frequencies because the NPS does not make much sense, and then you could use only one speaker. In this case you should probably put a couple of bridgre mono, because unfortunately it is only available in 8 ohms., but if you want adopt a push pull "the Linkwitz" the 15 "would be a little too oversized, and as such powers would return to space and 12", perhaps with greater excursion (type Peerless XLS12)
Tuesday, October 2, 2007
Star Personalized Chapstick
Audio / DIY / Speakers / QNPS-2 - The project: The amplifier
, 99 % of commercial amplifiers are based substantially on the final push-pull class AB.
It 's a clean and efficient circuit, with an infinite number of possible variants.
Improving the quality of the signal (and its management in critical situations) over this "standard" is not easy, whatever one may say the various supporters of this or that technology more or less esoteric, if only for the tried and tested project in thousands of versions and millions (!) of specimens.
Among the technologies that I find interesting are:
- tube amps
Personally I find the differences are so evident in the sound "tube", but I did a few tests of listening environments certainly not appropriate (Fairs et c.) . In theory, solid state devices can emulate the curves of the valves (MOSFET), but surely there are many other parameters that can influence. Certainly they have many disadvantages "practical", including three fatal to the application in the project: the dimensions of valves and output transformers, the need for high-voltage power (difficult to integrate into the structure) and the low power ( the QNPS-1 have been shown to require a hundred watts, at least for the woofer).
.
- Class A amplifiers
A single set of class A would certainly be tempting, especially considering that the power should be distributed in five different modules. The problems are twofold: the difficulty of finding modules (at a reasonable cost) of the power required (the Marantz, in fact, remain in class until about ten watts) and the frightening amount of heat they emit. Even if
to tolerate the "stove" result, it is rather difficult to integrate efficiently the monstrous heat sinks needed.
- class D amplifiers
The so-called class D amplifiers have characteristics very interesting circuit, as well as being compact, require little space for the radiators, due to their high efficiency.
can drive low impedance loads and are available in various configurations and power.
Despite the initial suspicion, they're conquering vast legions of audiophiles, attracted by the simplicity of the project (the end is just a chip) and the supposed cost-effectiveness. On the latter there would be no objection to my Marantz PM7200 have cost much less than a kit Hypex, considering power, chassis, connectors, et c.
The only real problem is that they are essentially closed boxes: beautiful dell'autocostruzione ends, where the aim is true to "understand" at the bottom of what is built.
- amplifiers without back-action
Qulche time ago I had a little chat with Roberto Delle Curti, great guru of the philosophy of "counter-counter-reaction."
Technically, the speech seems to me perfectly, even if it is (for me) difficult to assess the effects on sound quality (lack of) counter-reaction.
is even more difficult for me to understand how a circuit "completely" with no counter-reaction (especially solid state) can be stable.
In fact, these amps are made with excellent results. Then it depends on the counter-reaction or extreme quality of the project, components and assembly, is always questionable.
A middle way, which certainly abhor Roberto, would be to manage the portion of the signal in a "conventional" (operational, back-action et c.), and the power modules without feedback. The idea is that the delay introduced in the chain reaction, and the "reaction" by the inductive components are most critical in the power, connected to the speakers.
I have discarded long this last possibility, because apart from a few "high-end" (unpronounceable costs and the usual rhetoric of the gold wire "low noise "...), there were no products to dell'autocostruttore flow.
Lately however I discovered that there are long forms of the LC Audio (see the Danish case ...), the Millennium XP (formerly The End), to test production.
These modules are available in mono many different configurations, reasonably efficient, and feature as an option (thanks to them ...) of a loop, DC servo concession to function at low frequencies.
It 's a clean and efficient circuit, with an infinite number of possible variants.
Improving the quality of the signal (and its management in critical situations) over this "standard" is not easy, whatever one may say the various supporters of this or that technology more or less esoteric, if only for the tried and tested project in thousands of versions and millions (!) of specimens.
Among the technologies that I find interesting are:
- tube amps
Personally I find the differences are so evident in the sound "tube", but I did a few tests of listening environments certainly not appropriate (Fairs et c.) . In theory, solid state devices can emulate the curves of the valves (MOSFET), but surely there are many other parameters that can influence. Certainly they have many disadvantages "practical", including three fatal to the application in the project: the dimensions of valves and output transformers, the need for high-voltage power (difficult to integrate into the structure) and the low power ( the QNPS-1 have been shown to require a hundred watts, at least for the woofer).
.
- Class A amplifiers
A single set of class A would certainly be tempting, especially considering that the power should be distributed in five different modules. The problems are twofold: the difficulty of finding modules (at a reasonable cost) of the power required (the Marantz, in fact, remain in class until about ten watts) and the frightening amount of heat they emit. Even if
to tolerate the "stove" result, it is rather difficult to integrate efficiently the monstrous heat sinks needed.
- class D amplifiers
The so-called class D amplifiers have characteristics very interesting circuit, as well as being compact, require little space for the radiators, due to their high efficiency.
can drive low impedance loads and are available in various configurations and power.
Despite the initial suspicion, they're conquering vast legions of audiophiles, attracted by the simplicity of the project (the end is just a chip) and the supposed cost-effectiveness. On the latter there would be no objection to my Marantz PM7200 have cost much less than a kit Hypex, considering power, chassis, connectors, et c.
The only real problem is that they are essentially closed boxes: beautiful dell'autocostruzione ends, where the aim is true to "understand" at the bottom of what is built.
- amplifiers without back-action
Qulche time ago I had a little chat with Roberto Delle Curti, great guru of the philosophy of "counter-counter-reaction."
Technically, the speech seems to me perfectly, even if it is (for me) difficult to assess the effects on sound quality (lack of) counter-reaction.
is even more difficult for me to understand how a circuit "completely" with no counter-reaction (especially solid state) can be stable.
In fact, these amps are made with excellent results. Then it depends on the counter-reaction or extreme quality of the project, components and assembly, is always questionable.
A middle way, which certainly abhor Roberto, would be to manage the portion of the signal in a "conventional" (operational, back-action et c.), and the power modules without feedback. The idea is that the delay introduced in the chain reaction, and the "reaction" by the inductive components are most critical in the power, connected to the speakers.
I have discarded long this last possibility, because apart from a few "high-end" (unpronounceable costs and the usual rhetoric of the gold wire "low noise "...), there were no products to dell'autocostruttore flow.
Lately however I discovered that there are long forms of the LC Audio (see the Danish case ...), the Millennium XP (formerly The End), to test production.
These modules are available in mono many different configurations, reasonably efficient, and feature as an option (thanks to them ...) of a loop, DC servo concession to function at low frequencies.
The documentation is very good for once, and it shows that the product is designed for the amateur market (available schemes, bulk components et c.).
costs are certainly not those of the business models of the series, but not stratospheric.
So I think the initial size of the project based on these components.
costs are certainly not those of the business models of the series, but not stratospheric.
So I think the initial size of the project based on these components.
Low Back Pain While Taking Mucinex
Audio / DIY / Speakers / QNPS-2 - The project
During the implementation of QNPS-1, besides me a bit of practical experience, I began to think about the possible evolution of the project.
I would say that the developments could go in two directions:
a) improving the design specifications and
b) solve the problems / constraints encountered in the first implementation
With regard to the specific possible developments are currently as follows:
- integration of electronics in the speaker. This greatly simplify the wiring harness, and would reduce the uncertainties related to Qt at low frequencies.
- replacement of commercial amplifiers with single high-quality (Class A? Class D? Tubes? Open end?). This, in addition to (perhaps) improve the sound, would ensure a consistent baseline across all channels, and simplify the integration of the above.
.
- increasing the streets. Without risking too much with crossover cross-over, you might groped a five-way (two octaves per band): Sub, Woofer, Mid, Mid-High, Tweeter. This would improve the spatial accuracy according to the NPS.
- managing the effects of diffraction. Size allowing you might think of a geometry that improves the situation, at least on average.
Regarding the current limitations, surely there could be improvements in the following areas:
.
- simplifying the assembly. The sequence of assembly should be designed at the table, so that you can paste pieces of this size by yourself ripetto the tolerances set.
.
- panel-interface structure. If you keep the current geometry, the system is now designed to mount the panel "simple dipole" structure "H-frame dipole.
.
- to improve the finish. The tubing should be trapped without curbs and exposed components must be painted before final assembly.
For the moment I decide to split the posts made in various parts of the project:
- structure and geometry
- transducers
- cross-over
- amplifier
Image Of Mottled Palm
Audio / DIY / Electronics - Contactor
Very 
Very
embedded systems often have a control bus that allows you to make stand-by all devices with a single control.
In my case, it is a nice convenience: my equipment because they are scattered around the room, and certainly send a signal stand-by is a rational approach to rewire the entire system electric!
Unfortunately this is only possible with equipment ready: for others to do is connect to the outlets controlled. In systems
cheapest outlets are fed back power the device, while in some refinements are controlled via stand-by function, as in the case of my Marantz. The problem of controlled
taken, however, is the load that they are able to endure: it is usually very low, and given the ideas that are able to generate megacondensatori of high-fidelity, is not a problem recently.
To give one example, the Marantz PM7200 100 W total on the statement just made. To resolve
the problem I thought I'd take a small contactor: a simple normally open relay controlled by a coil 220.
In this way the absorption on the tricks is limited to coil excitation current, which is absolutely ridiculous.
I assumed that there was already a ready-made ciabatta bread, and yet in the end I had to make it to me ... as usual!
In practice I had to assemble in a small box control the contactor and an outlet, connected to the first "control signal" (the output of 220V outlets subsidiaries), and the second power through the relay.
All for a cost of about € 30.
for the "savings stupid" I took the relay cheaper (20A, 4500 W. ..), without noticing that just was markedly more expensive "quiet" ... and now I understand why!
power-CLACK is a BUMP that added to the woofer is a danger that is about to explode all ...
Anyway it works well, plus introducing a small delay in the start-up sequence, which never hurts.
In my case, it is a nice convenience: my equipment because they are scattered around the room, and certainly send a signal stand-by is a rational approach to rewire the entire system electric!
Unfortunately this is only possible with equipment ready: for others to do is connect to the outlets controlled. In systems
cheapest outlets are fed back power the device, while in some refinements are controlled via stand-by function, as in the case of my Marantz. The problem of controlled
taken, however, is the load that they are able to endure: it is usually very low, and given the ideas that are able to generate megacondensatori of high-fidelity, is not a problem recently.
To give one example, the Marantz PM7200 100 W total on the statement just made. To resolve
the problem I thought I'd take a small contactor: a simple normally open relay controlled by a coil 220.
In this way the absorption on the tricks is limited to coil excitation current, which is absolutely ridiculous.
I assumed that there was already a ready-made ciabatta bread, and yet in the end I had to make it to me ... as usual!
In practice I had to assemble in a small box control the contactor and an outlet, connected to the first "control signal" (the output of 220V outlets subsidiaries), and the second power through the relay.
All for a cost of about € 30.
for the "savings stupid" I took the relay cheaper (20A, 4500 W. ..), without noticing that just was markedly more expensive "quiet" ... and now I understand why!
power-CLACK is a BUMP that added to the woofer is a danger that is about to explode all ...
Anyway it works well, plus introducing a small delay in the start-up sequence, which never hurts.
Monday, October 1, 2007
Can I Use A Tinted Motorcycle Helmet At Night?
Audio / DIY / Electronics - Volume
However, some come to build multiple potentiometers (motorized and calibration procedures "micrometer" ..) in order to vary the final volume of intervening (In a different way) on all the various gains in the chain.
One problem that I think sooner or later all the DIY meet is that, seemingly trivial, to control the volume.
When you start a chain of connected devices of various types, each of these "wants" at a "certain" signal for which the benefits noise, impedance et c. are "optimal".
Usually problems are of three types:
a) the signal is too weak (in some part of the chain) and the signal to noise ratio degrades
b) the S / N ratio is good in analog, but since the signal is All Time Low is sampled with a low resolution digital
c) the signal is too strong (the worst situation ever, because the electronics saturates very distorting the sound).
When you start a chain of connected devices of various types, each of these "wants" at a "certain" signal for which the benefits noise, impedance et c. are "optimal".
Usually problems are of three types:
a) the signal is too weak (in some part of the chain) and the signal to noise ratio degrades
b) the S / N ratio is good in analog, but since the signal is All Time Low is sampled with a low resolution digital
c) the signal is too strong (the worst situation ever, because the electronics saturates very distorting the sound).
must say that once the situation was much worse, because of the variety of different sources (phono. ..), so it was essential to have a pre-amp can "normalize" the signal (voltage, impedance, spectrum ...) without degrading too.
now many sources are digital, and above all the outputs are more standardized, as well as having very little problems almost always impedances (and in the case of digital signals, irrelevant).
levels of CD, for example, in addition to having a dynamic range of intrinsically pre-defined, almost all are standard on the highest peak. Of course there are exceptions: for example CD Muse strangely always peaks of about ten dB above the standard ...
However, some come to build multiple potentiometers (motorized and calibration procedures "micrometer" ..) in order to vary the final volume of intervening (In a different way) on all the various gains in the chain.
In my case the problems are two: the drive balanced / unbalanced (ART Cleanbox) above the final, and DSP (Behringer DEQ2496).
In the first case, I discovered that for the same output, varying in one direction or the gain compared to an average value, the noise increases significantly. This unfortunately is a typical behavior of the op (it's noticeable even on the end), but I did not think he could "feel".
In the second case, hearing music at low volume, my feeling is that the DSP works badly (a duller sound) I have verified this several times easier thanks to a control that allows easy to vary the input signal (and equally out) on the DEQ, with the same volume.
So I have a problem of dynamics, especially because I like to hear rock music at high volume (or maybe a little dull ...), while my wife feels more classical music at low volume.
In the first case, I discovered that for the same output, varying in one direction or the gain compared to an average value, the noise increases significantly. This unfortunately is a typical behavior of the op (it's noticeable even on the end), but I did not think he could "feel".
In the second case, hearing music at low volume, my feeling is that the DSP works badly (a duller sound) I have verified this several times easier thanks to a control that allows easy to vary the input signal (and equally out) on the DEQ, with the same volume.
So I have a problem of dynamics, especially because I like to hear rock music at high volume (or maybe a little dull ...), while my wife feels more classical music at low volume.
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