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Old 2nd December 2019, 09:42 PM   #51
Gnobuddy is offline Gnobuddy  Canada
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Originally Posted by Allan M View Post
I can see what you mean about the death of hi-fi.
I think it's pretty literal. IMO, it's not that good audio equipment doesn't exist. Rather, it's that virtually nobody cares any longer. Public interest has moved on to something else (most likely, poking at their phones every few minutes.) Therefore, good-sounding audio equipment - speakers in particular - have become somewhat of an endangered species.

Many electronics manufacturers that used to be household names don't even make stereo equipment any longer. Generic chain stores like Montgomery Ward (now defunct), Target (bankrupt in Canada, struggling in the US), and Sears (struggling, in bankruptcy protection) used to sell speakers and amps and receivers, but they don't any longer.

Perhaps more telling, in the last several years, I can't recall having been in a home (other than mine) that contained separate stereo loudspeakers or an amp. Usually there's a TV, with awful built-in 2" or 3" speakers, and that's what the homeowner(s) listen to.

Music? Earbuds plugged into a phone playing MP3 tracks is almost universal. If there is a music enthusiast in the house, maybe there's an overpriced Bluetooth powered speaker, with its own awful 2" or 3" built-in speaker, housed in an enclosure that looks as little like a loudspeaker as possible.

Nobody whom I know currently (in this part of Canada) owns a home theatre system. The ones I saw in Los Angeles homes a decade ago typically featured four satellite speakers in enclosures that were maybe 3" or 3.5" cubes, one "sound bar" that has exactly the wrong design for a centre channel (a horizontal line-array disperses sound vertically, and beams it horizontally, the opposite of what you want), and a "subwoofer" that is about an 8" cube with a 6-inch "woofer" in it.

The little satellite speakers struggle to reproduce anything below maybe 500 Hz, the little subwoofer booms loudly at about 100 Hz, and there is a yawning gap in between the upper frequency limit of the subwoofer, and the lower frequency limit of the satellite speakers. Sound quality is somewhere between mediocre and awful, and the owners probably shelled out $500 USD or more for the privilege.

The head-scratcher for me is that I've heard vintage valve AM radios - built in the 1950s - that sounded better to me. There was nothing above 5 kHz, but at least the bass was rich and warm, and the limited bass extension balanced the limited treble extension, so overall the sonic balance wasn't too bad. Now when I hear someone listen to music from the penny-sized speaker in their phone, all treble and no bass, I don't know how they can stand it.

I've read enough history books to know that fashions come, and fashions go. Home Hi-Fi was fashionable for a while, perhaps from roughly the 1960s through the 1990s. It lasted longer than some other fashions did; North America was absolutely mad about mandolins from roughly the 1880s until about 1915.


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Old 3rd December 2019, 02:57 AM   #52
Gnobuddy is offline Gnobuddy  Canada
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Originally Posted by Allan M View Post
Even the big names like Marshall, Fender and Orange?
If you come from the world of Hi-Fi audio, guitar speakers, and guitar amps, are a trip down Alice's rabbit-hole. None of the rules you're familiar with apply...flat frequency responses sound bad, extended treble response sounds bad, bass response below 83 Hz is utterly useless (that's the lowest note you can get from a guitar in standard tuning), and enormous amounts of distortion - the right kind of distortion - is a good thing.


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Old 3rd December 2019, 11:59 AM   #53
Allan M is online now Allan M
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Originally Posted by Gnobuddy View Post
... Rather, it's that virtually nobody cares any longer. Public interest has moved on to something else (most likely, poking at their phones every few minutes.) ...

Music? Earbuds plugged into a phone playing MP3 tracks is almost universal. If there is a music enthusiast in the house, maybe there's an overpriced Bluetooth powered speaker, with its own awful 2" or 3" built-in speaker, housed in an enclosure that looks as little like a loudspeaker as possible.
Smartphones seem to have taken people's sense of spatial awareness altogether. I am continually having to move aside to avoid running into them. Perhaps this is connected to their disinterest in spatial sound and music. Even the dynamics of the music they listen to with earphones has been mostly flattened out. They live in a flat world, approximately 110 mm x 65 mm.

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Many electronics manufacturers that used to be household names don't even make stereo equipment any longer. ...
I've noticed. At best, usually, it will be mini 5.1 systems to go with their big TVs. Even the big home-wares and electronics stores rarely have floor-standing speakers. Some who do carry them just have them stacked in boxes along one wall.

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Originally Posted by Gnobuddy View Post
If you come from the world of Hi-Fi audio, guitar speakers, and guitar amps, are a trip down Alice's rabbit-hole. None of the rules you're familiar with apply...flat frequency responses sound bad, extended treble response sounds bad, bass response below 83 Hz is utterly useless (that's the lowest note you can get from a guitar in standard tuning), and enormous amounts of distortion - the right kind of distortion - is a good thing.
What about bass guitar amplifiers? The open E fundamental is about 40 Hz. Open B on a five-string is around 30 Hz.

Is getting a good sound for guitar amps just a matter of experimenting and trial-and-error then?
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Old 4th December 2019, 06:47 PM   #54
Gnobuddy is offline Gnobuddy  Canada
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Originally Posted by Allan M View Post
What about bass guitar amplifiers? The open E fundamental is about 40 Hz. Open B on a five-string is around 30 Hz.

Is getting a good sound for guitar amps just a matter of experimenting and trial-and-error then?
We might both get lynched if we talk about instrument amplifiers for too long on this forum...there's a separate forum for us untouchables!

I dabble a little in bass, and when going into the P.A., I note that both my 4-string and 5-string basses sound better if I turn on the 60-Hz high pass filter in my preamp - clearer, less muddy, and just as deep-sounding. I also note that my 4-string bass sounds crisper and more articulate plugged into my little Acoustic B20 bass guitar amp with its 12" speaker, than it does if I go direct. IMO, a little high-pass filtering actually makes the bass sound less muddy and makes it more audible in the mix.

I've also looked up a few spectrograms of bass guitar signals - most of the time, the strongest Fourier component is the 4th harmonic of the fundamental note! So the 30-Hz low B on a 5-string guitar, when plucked, is mostly spitting out a signal at 120 Hz. And so on, over most of the musically useful range of the instrument, especially the lowest couple of octaves.

This makes sense when you consider that the fretboard occupies more than 3/4 of the length of the string on almost any modern bass (24 frets takes up 3/4 of string length). So the pickups, and the player's fingers or guitar pick, hit the string rather close to its end, and quite far from its middle. This puts energy into upper harmonics rather than the fundamental.

Other than that, I don't know much about bass guitar preamp or speaker design. The speakers are usually designed using Thiele-Small parameters, unlike guitar speakers; the enclosures are usually ported to produce reasonable levels of bass from reasonable-sized enclosures.

But there is little public information on how onboard bass-guitar preamps are "voiced" (EQ). Bass players claim that different-brand preamps and speakers sound very different, which I think implies they must have audible differences in EQ, since there isn't much else to distinguish them.

As for guitar-amps, I don't think there has been much evolution for decades. Leonidas Fender found the recipe for what guitarists call "clean tones" in the 1960s, maybe a bit earlier. Jim Marshall and his tech copied the Fender Bassman, then tweaked and evolved the design to create signature classic-rock sounds of the late '60s and '70s. In the 1980s the gain and distortion levels got cranked up until guitars started to sound like power tools grinding on the proverbial tin roof.

And since then, for nearly four decades, most developmental effort seems to have gone into re-creating vintage valve amp designs, or trying to make semiconductors sound like valves (vacuum tubes), or adding on useful features like direct-out jacks and speaker attenuators. I don't think there has been much by way of new or improved sounds, really. But that's just my opinion.


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Old 5th December 2019, 02:00 PM   #55
Allan M is online now Allan M
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Originally Posted by Gnobuddy View Post
I dabble a little in bass, and when going into the P.A., I note that both my 4-string and 5-string basses sound better if I turn on the 60-Hz high pass filter in my preamp - clearer, less muddy, and just as deep-sounding. I also note that my 4-string bass sounds crisper and more articulate plugged into my little Acoustic B20 bass guitar amp with its 12" speaker, than it does if I go direct. IMO, a little high-pass filtering actually makes the bass sound less muddy and makes it more audible in the mix.
I recently bought an Orange Crush Bass 25 to learn bass guitar with. I think it has an 8" driver and it's ported. It's not earth-shaking but it has a nice sound.

Quote:
I've also looked up a few spectrograms of bass guitar signals - most of the time, the strongest Fourier component is the 4th harmonic of the fundamental note! So the 30-Hz low B on a 5-string guitar, when plucked, is mostly spitting out a signal at 120 Hz. And so on, over most of the musically useful range of the instrument, especially the lowest couple of octaves.

This makes sense when you consider that the fretboard occupies more than 3/4 of the length of the string on almost any modern bass (24 frets takes up 3/4 of string length). So the pickups, and the player's fingers or guitar pick, hit the string rather close to its end, and quite far from its middle. This puts energy into upper harmonics rather than the fundamental.
Does this mean I don't need a subwoofer to listen to rock music?

Quote:
Other than that, I don't know much about bass guitar preamp or speaker design. The speakers are usually designed using Thiele-Small parameters, unlike guitar speakers; the enclosures are usually ported to produce reasonable levels of bass from reasonable-sized enclosures.

But there is little public information on how onboard bass-guitar preamps are "voiced" (EQ). Bass players claim that different-brand preamps and speakers sound very different, which I think implies they must have audible differences in EQ, since there isn't much else to distinguish them.

As for guitar-amps, I don't think there has been much evolution for decades. Leonidas Fender found the recipe for what guitarists call "clean tones" in the 1960s, maybe a bit earlier. Jim Marshall and his tech copied the Fender Bassman, then tweaked and evolved the design to create signature classic-rock sounds of the late '60s and '70s. In the 1980s the gain and distortion levels got cranked up until guitars started to sound like power tools grinding on the proverbial tin roof.
If they know the sound they want, I guess they don't need accurate test equipment.

Quote:
And since then, for nearly four decades, most developmental effort seems to have gone into re-creating vintage valve amp designs, or trying to make semiconductors sound like valves (vacuum tubes), or adding on useful features like direct-out jacks and speaker attenuators. I don't think there has been much by way of new or improved sounds, really. But that's just my opinion.
Semiconductor circuits can be made which emulate the valve characteristic. I wouldn't have thought that would be a big deal.
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Old 5th December 2019, 09:48 PM   #56
Gnobuddy is offline Gnobuddy  Canada
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Originally Posted by Allan M View Post
Does this mean I don't need a subwoofer to listen to rock music?
I like what a subwoofer adds to rock music, and it does add something. Maybe keyboards and drums that reach below bass guitar frequencies; maybe bass guitar itself, cleverly recorded and EQ'd and mixed, can use more of that bottom octave without turning to mud, as it does in a live music situation.
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Originally Posted by Allan M View Post
Semiconductor circuits can be made which emulate the valve characteristic.
Which characteristic would that be? Triode? Pentode? At which bias condition? With which load impedance?

Both triodes and pentodes produce a variety of nonlinear effects, varying with all the above factors. Unipolar grid current flow through interstage coupling capacitors causes dynamic shifts in DC bias that vary with guitar signal level and frequency, causing time-varying transfer characteristics and distortions.

All of this mostly unresearched and undocumented stuff seems to contribute to the sound of a good valve guitar amp.(Though Carvin once made a line of solid-state guitar amps that included carefully emulated dynamic duty-cycle modulation of the output waveform.)

Also, IMO analogue SS valve emulations tend to go abruptly from too-clean to too-distorted as signal level increases, ruining the smoothly progressive distortion characteristics that allow expressive electric guitar playing.

These seem to be some of the reasons why most solid-state emulations have ended up sounding boring and buzzy, or harsh and unvarying, lacking the subtlety you get from a good valve guitar amp.
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Originally Posted by Allan M View Post
I wouldn't have thought that would be a big deal.
I thought the same thing at one time. I was quite wrong!

The facts: thousands of attempts have been made over at least six decades, after transistors became widely available circa 1960. Most have been total failures, a few found brief niche success, none actually replaced valve guitar amps for long in the hands of top-notch pro guitarists in blues, rock, pop, and other similar types of music.

I've made a fair number of stabs at the problem myself, trying everything from piecewise-linear diode/resistor feedback networks around op-amps to clever tricks with JFETs and MOSFET logic inverters biased into quasi-linear operation. All of them did something vaguely valvey, but none came close to completely emulating a good tube amp.

That's not to say you won't be the first one to succeed, but the odds are heavily against you.

There have been successes in recent years, but not with analogue circuits. Only with powerful digital signal processing, using secret and proprietary algorithms that have been refined over at least the last thirty years (that's when crappy-sounding early DSP modelling amps started to be marketed by the likes of Line 6), and taking advantage of the constantly increasing performance of digital chips over the years.

A few years ago, the AmpliFIRE products from Atomic Amps were some of the first convincing tube-amp simulations I ever heard (to my ears, obviously.) More recently, the Boss Katana 50 and 100 have set the standard for affordable solid-state guitar amps that sound (very much) like really good tube amps in many situations.

We are now far from Hi-Fi loudspeaker systems, and if this thread is to continue in this vein, it should be in the Instruments & Amps forum.


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Old 6th December 2019, 11:12 AM   #57
Allan M is online now Allan M
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Originally Posted by Gnobuddy View Post
Which characteristic would that be? Triode? Pentode? At which bias condition? With which load impedance?

Both triodes and pentodes produce a variety of nonlinear effects, varying with all the above factors. Unipolar grid current flow through interstage coupling capacitors causes dynamic shifts in DC bias that vary with guitar signal level and frequency, causing time-varying transfer characteristics and distortions.

All of this mostly unresearched and undocumented stuff seems to contribute to the sound of a good valve guitar amp.(Though Carvin once made a line of solid-state guitar amps that included carefully emulated dynamic duty-cycle modulation of the output waveform.)

Also, IMO analogue SS valve emulations tend to go abruptly from too-clean to too-distorted as signal level increases, ruining the smoothly progressive distortion characteristics that allow expressive electric guitar playing.

These seem to be some of the reasons why most solid-state emulations have ended up sounding boring and buzzy, or harsh and unvarying, lacking the subtlety you get from a good valve guitar amp.
It's harder than I thought. I guess the best thing is give up trying to make transistors act like valves and put up with the extra weight of the output transformer and less compact head units. Or do the best you can with inherent transistor characteristics.

It's like the valve amplifier is part of the instrument for amplified guitars. Perhaps the thing to do with transistor amplifiers and effects is use what inherent features of transistors there are to produce different yet equally pleasant sounds.

Quote:
I thought the same thing at one time. I was quite wrong!

The facts: thousands of attempts have been made over at least six decades, after transistors became widely available circa 1960. Most have been total failures, a few found brief niche success, none actually replaced valve guitar amps for long in the hands of top-notch pro guitarists in blues, rock, pop, and other similar types of music.

I've made a fair number of stabs at the problem myself, trying everything from piecewise-linear diode/resistor feedback networks around op-amps to clever tricks with JFETs and MOSFET logic inverters biased into quasi-linear operation. All of them did something vaguely valvey, but none came close to completely emulating a good tube amp.

That's not to say you won't be the first one to succeed, but the odds are heavily against you.

There have been successes in recent years, but not with analogue circuits. Only with powerful digital signal processing, using secret and proprietary algorithms that have been refined over at least the last thirty years (that's when crappy-sounding early DSP modelling amps started to be marketed by the likes of Line 6), and taking advantage of the constantly increasing performance of digital chips over the years.

A few years ago, the AmpliFIRE products from Atomic Amps were some of the first convincing tube-amp simulations I ever heard (to my ears, obviously.) More recently, the Boss Katana 50 and 100 have set the standard for affordable solid-state guitar amps that sound (very much) like really good tube amps in many situations.
I guess digital simulations can do whatever you want them to.

Quote:
We are now far from Hi-Fi loudspeaker systems, and if this thread is to continue in this vein, it should be in the Instruments & Amps forum.
Yes. Will somebody move this discussion there? Is it a forum on this same site?
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Old 6th December 2019, 04:16 PM   #58
Gnobuddy is offline Gnobuddy  Canada
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Originally Posted by Allan M View Post
It's like the valve amplifier is part of the instrument for amplified guitars.
I think that's the conclusion many of have ended up with. Even the loudspeaker is part of the instrument - it contributes quite a lot of EQ, typically a slow treble rise of as much as 10 dB by 3.5 kHz, followed by an abrupt downward plunge that helps to suppress harsh-sounding high frequencies from distorted guitar.
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Originally Posted by Allan M View Post
I guess digital simulations can do whatever you want them to.
In principle, yes. In practice, not always!

There used to be an insider joke that goes something like this: a software research scientist works on solving yesterday's computational problems with tomorrow's computing hardware, while a production software engineer has to solve tomorrow's problems with yesterday's hardware.

For most of their thirty-year history, hardware digital sims universally sounded awful to me, buzzy, monotonous, unpleasant, harsh, and lifeless. The computing power available in an affordable DSP chip was limited, and I think the software algorithms for emulating valve amps were also inadequate. I think many fell into the trap of believing that all you had to do was make a rigidly unvarying nonlinear transfer function, and all would be well. But it wasn't.

Better results were starting to be possible with software guitar amp sims running on an actual personal computer, rather than a little DSP chip in a $350 guitar pedal. So evidently having vastly bigger processing power available did make a difference.

For me, the hardware sims finally began to change just two or three years ago, when I first heard video demonstrations of the (fairly expensive) Atomic Amps AmpliFIRE products. Then the Boss Katana line came along, at half or a third of the price of the Atomic Amps stuff, and blew everyone else completely out of the water with the mix of sound quality, price, and features.

The spray from that epic explosion hasn't settled yet, as for the last couple of years the Katana line has outsold every similar product by a vast margin, and all the other manufacturers must be tearing their hair out trying to make a product that will claw back some sales for them.
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Originally Posted by Allan M View Post
Is it a forum on this same site?
Indeed: https://www.diyaudio.com/forums/instruments-and-amps/

You could start your own thread there, if you wanted to.

I'm told (and there is evidence in old posts and threads) that there was a lot more interest in unique and creative DIY guitar amps on that forum several years ago, before I was a member here. When I joined the forum was more repair oriented ("How can I fix my buzzing FlapJack 455 amplifier?"), and that trend, sadly, seems to be continuing, along with a progressive decline in the rate at which new threads are created.

I'm saddened, but not totally surprised. People tend to be at their creative peak in their twenties, and there are few twenty-somethings interested in electronics nowadays.

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Old 7th December 2019, 06:53 AM   #59
Allan M is online now Allan M
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Originally Posted by Gnobuddy View Post
In principle, yes. In practice, not always!

...

For most of their thirty-year history, hardware digital sims universally sounded awful to me, buzzy, monotonous, unpleasant, harsh, and lifeless. The computing power available in an affordable DSP chip was limited, and I think the software algorithms for emulating valve amps were also inadequate. I think many fell into the trap of believing that all you had to do was make a rigidly unvarying nonlinear transfer function, and all would be well. But it wasn't.

Better results were starting to be possible with software guitar amp sims running on an actual personal computer, rather than a little DSP chip in a $350 guitar pedal. So evidently having vastly bigger processing power available did make a difference.
I forgot about processing power limitations. However, I was thinking more of an amplifier unit that emulates a valve circuit rather than just an effects pedal, which would have space for a more sophisticated digital processor.

Quote:
For me, the hardware sims finally began to change just two or three years ago, when I first heard video demonstrations of the (fairly expensive) Atomic Amps AmpliFIRE products. Then the Boss Katana line came along, at half or a third of the price of the Atomic Amps stuff, and blew everyone else completely out of the water with the mix of sound quality, price, and features.

The spray from that epic explosion hasn't settled yet, as for the last couple of years the Katana line has outsold every similar product by a vast margin, and all the other manufacturers must be tearing their hair out trying to make a product that will claw back some sales for them.
Perhaps big companies aren't so stable as we tend to assume. One technical advance is all it takes to fold a whole industry and create a new giant.

Quote:
Indeed: https://www.diyaudio.com/forums/instruments-and-amps/

You could start your own thread there, if you wanted to.

I'm told (and there is evidence in old posts and threads) that there was a lot more interest in unique and creative DIY guitar amps on that forum several years ago, before I was a member here. When I joined the forum was more repair oriented ("How can I fix my buzzing FlapJack 455 amplifier?"), and that trend, sadly, seems to be continuing, along with a progressive decline in the rate at which new threads are created.
Although I have been more interested in hi-fi audio, guitar amps are an interesting topic as well. The electronic and acoustic side of amplified instruments makes it interesting. It's a reversal of hi-fi audio: Instead of trying to make an amplifier which acts like a "straight wire with gain", the qualities of the devices are being creatively exploited.

Quote:
I'm saddened, but not totally surprised. People tend to be at their creative peak in their twenties, and there are few twenty-somethings interested in electronics nowadays.
I am surprised. In Australia, there are several popular, electronics hobby magazines. Today, they are oriented toward coding as well as mechanics and construction in addition to electronics. The projects combine the three fields to make working devices of all kinds. A few are more oriented to school-age kids, at a more basic level, but with some good basic technical instruction. It seems to be all the rage. Trading on the "geek cool" wave to some extent but also moving with the coming AI industry.

No doubt you have already made some attempts to stir interest in the creative DIY in that forum? I'd be interested in joining it to pursue that side of audio.
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Old 8th December 2019, 06:01 PM   #60
Gnobuddy is offline Gnobuddy  Canada
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I was thinking more of an amplifier unit that emulates a valve circuit rather than just an effects pedal, which would have space for a more sophisticated digital processor.
I didn't express myself very well, but that is exactly what I was talking about. For a long time, manufacturers have been selling guitar processors intended to be placed on the floor, with foot-operated "stomp switches", in housings bigger than a traditional analogue guitar effects box, and using DSP to emulate valve circuitry, often an entire guitar amplifier plus a chain of guitar effects. Boss, Digitech, Line 6, Zoom, and a variety of other companies have sold products like this. In North America they're often referred to as multi-effects pedals, even though many include valve amp simulation and not just effects simulation.

These were/are intended to connect directly to a flat-response P.A., powered speaker, or in a pinch, an existing guitar amp. In principle, all you'd need for a complete guitar rig is your guitar, one of these boxes, and your powered speaker. The multi-fx box provides a variety of simulations claiming to sound like famous valve guitar amps from the past, along with a variety of simulations claiming to duplicate the various guitar effects pedals you might otherwise have on your pedalboard.

I've bought several over the years, and always ended up disappointed by the sound quality of the emulated valve amplifier(s). The advertising always claimed to deliver something along the lines of "The sounds of one hundred glorious vintage guitar amplifiers in one tiny box!", while early Line 6 products delivered a reality closer to "The sounds of one hundred kazoos in one tiny box!"
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Originally Posted by Allan M View Post
It's a reversal of hi-fi audio: Instead of trying to make an amplifier which acts like a "straight wire with gain", the qualities of the devices are being creatively exploited.
Exactly! IMO this is quite typical of what happens when art meets technology: creative artists push the technology past the limits envisioned by the engineer, until the technology breaks, and then the artist creates her most expressive art using the freshly exposed flaws in the technology.

I expect the "engineer" who invented the first paint-brush intended it to produce a smooth, uniform streak of colour. But artists quickly found flaws in the technology - make the paint too dry, and you get streaky and non-uniform marks on the canvas; make it too wet, you create a wash of non-uniform colour; change the type of solvent or the amount of pigment, and you end up with visible brush strokes instead of a smooth wash. And very soon all of these flaws in paintbrush technology became parts of any good painter's repertoire of techniques.

On the guitar amp front, Leonidas Fender knew just enough about electronics to pick up a soldering iron and copy standard Hi-Fi valve circuits out of the back of RCA valve catalogues to create his early guitar amplifiers. The music he favoured - country and surf - was all based around the clean, bright, undistorted sound of the guitar, and that's what he intended his amplifiers to produce. They were based on standard Hi-Fi circuitry of the time, minimally altered to accept guitar signals; Merlin Blencowe (aka "The Valve Wizard") refers to them as "Adequate-Fi", as good a description as any!

Early Fender amplifier "designs" that, quite unintentionally, were easily driven into audible distortion (like the 5E3 tweed Deluxe) were seen as failures, and Leonidas and his tech began tweaking his amplifiers to create the cleanest guitar tones they could conjure up. Copying a tone control design originally engineered for the Williamson Hi-Fi amplifier and raising power supply voltages eventually did the trick, and Fenders "Blackface" amps were born.

Then some artist - likely a blues guitarist - turned up his Fender amp louder than it was ever intended to go, and found out that the sound became distorted. Any audio engineer would immediately have turned the amplifier back down, but our hypothetical artist found that the distorted guitar sound sustained better, allowed for more expressive playing, and caught the listener's attention more than the clean "ping!" of an undistorted guitar note.

Leo either never knew, or never cared, and kept making clean guitar amplifiers; but Jim Marshall and his amp repair tech in the UK stole Leo Fender's Bassman amplifier design to create their first amplifier, noticed the emergence of rock music with its distorted guitar tones in Britian, and began to modify their amplifier designs to distort more easily, rather than to stay clean as loud as possible. Eventually they took this to quite an extreme, with their now-famous "cold clipper" amplifier stage, which is a triode valve biased almost into class B operation, so that it operates almost like a half-wave-rectifier rather than a linear audio amplifier.
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Originally Posted by Allan M View Post
In Australia, there are several popular, electronics hobby magazines.
The ones I used to buy in the USA in the 1990s all went out of business, one by one.

Many years later, "Make" magazine arrived, and kick-started a renaissance in the oh-so-shocking idea that you could actually make things yourself, rather than buying everything from a shop. "Make" has found a niche audience and still exists today.

While I'm grateful for its existence, I doubt it has captured the attention of more than a tiny fraction of today's youth.

There was a survey a couple of years ago that found the median age of diyAudio members was 55. I bet that number is steadily increasing, too.
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Originally Posted by Allan M View Post
No doubt you have already made some attempts to stir interest in the creative DIY in that forum?
That I have, but there are others much more prolific than I have ever been. Like Tubelab_Com (George), an engineer with the creative bent of an artist and the "Who cares if it breaks?" attitude of a punk-rocker, who has done more amazing and improbable things with valves than any normal engineer ever imagined doing.


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