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Post Subject:
Germanium
Germanium
Hi
Suddenly, there is a lot of Buzz(!) about Germanium transistors in
boutique effects etc. I have a couple of 70's effects and an amp that
contains these and no-way do they sound any better than
silicone/modern equivalents. Why are people going mad for them all of
a sudden??
Am I missing something?
MG
UK
Hi
Suddenly, there is a lot of Buzz(!) about Germanium transistors in
boutique effects etc. I have a couple of 70's effects and an amp that
contains these and no-way do they sound any better than
silicone/modern equivalents. Why are people going mad for them all of
a sudden??
Am I missing something?
MG
UK
Re: Germanium
"MG" <100550.3170@compuserve . com > wrote in message
news:482c9d72.82879935@news . fr eeuk . net ...
> Hi
>
> Suddenly, there is a lot of Buzz(!) about Germanium transistors in
> boutique effects etc. I have a couple of 70's effects and an amp that
> contains these and no-way do they sound any better than
> silicone/modern equivalents. Why are people going mad for them all of
> a sudden??
>
> Am I missing something?
>
> MG
> UK
------------
No, you're not missing anything - these fads and mojo tales come and go.
Germanium-based semiconductors are generally inferior to silicon, but they
have some differing properties - such as a lower forward voltage drop - that
are sometimes useful. The sound of semiconductor distortion is far more
dependent on the specific circuitry the diodes or transistors are used in
than on the semiconductor material itself.
Guitar pedal design engineering, repairs, and custom mods:
* howard.davis2.home.att . net /
"MG" <100550.3170@compuserve . com > wrote in message
news:482c9d72.82879935@news . fr eeuk . net ...
> Hi
>
> Suddenly, there is a lot of Buzz(!) about Germanium transistors in
> boutique effects etc. I have a couple of 70's effects and an amp that
> contains these and no-way do they sound any better than
> silicone/modern equivalents. Why are people going mad for them all of
> a sudden??
>
> Am I missing something?
>
> MG
> UK
------------
No, you're not missing anything - these fads and mojo tales come and go.
Germanium-based semiconductors are generally inferior to silicon, but they
have some differing properties - such as a lower forward voltage drop - that
are sometimes useful. The sound of semiconductor distortion is far more
dependent on the specific circuitry the diodes or transistors are used in
than on the semiconductor material itself.
Guitar pedal design engineering, repairs, and custom mods:
* howard.davis2.home.att . net /
Re: Germanium
Howard Davis wrote:
> The sound of semiconductor distortion is far more
> dependent on the specific circuitry the diodes or transistors are used in
> than on the semiconductor material itself.
Absolutely right.
I suspect what the promoters of 'germanium' circuitry are seeking to achieve is
the sound of old circuit design principles.
I'm sure that you could put a silicon device in there (suitably re-biased) and
you'd get the same effect.
Graham
Howard Davis wrote:
> The sound of semiconductor distortion is far more
> dependent on the specific circuitry the diodes or transistors are used in
> than on the semiconductor material itself.
Absolutely right.
I suspect what the promoters of 'germanium' circuitry are seeking to achieve is
the sound of old circuit design principles.
I'm sure that you could put a silicon device in there (suitably re-biased) and
you'd get the same effect.
Graham
Re: Germanium
>I'm sure that you could put a silicon device in there (suitably re-biased) and
>you'd get the same effect.
No.
Try to create a Rangmaster with Sil, and then with Gem, and you will find
it's 2 other worlds. Also, why do you think the Rangemaster worked so well
with 'rock stars' in the UK, instead of the US, even when enough of them were
available in the US? UK amps with small input/grid resistors hindered the
effect the R/Master's. Hiwatt's (with no resistor) kicked ass with this effect.
Gem devices are (in this day and age) unstable, and need to be matched, as do
all the smart folks know, NTE Gem devices are unstable, and one must go thru 100
to get 6..if you are that lucky. OLD NOS Gem parts are no better, as it's the
nature of the beast, NOT the device. But G devices do 'play' better then S...
There is no Santa Claus on the Midnight Train..
Nor is there any 'fritz' in the RCA future. Idiot me, I dived in that pool again.
..thank God I could swim out with both legs kicking..
JJTj
I've been a drag racer on LSD,
and I rode bare-assed on top of the sphinx,
I even had a gorilla on the slopes of kismet,
and man, that was fun for a while you bet but...
Bikini girls with machine guns,
Bikini girls with machine guns,
that stuff will kill ya, and it's loaded with fun,
Bikini girls with machine guns
well I savored many foriegn kinds of delicacies,
intoxicated til I can't tell what the hell I could see,
had all the violence and liquor within close reach,
but all bars, pills and threeways lead me back to the beach...
...yeah...
Bikini girls with machine guns,
Bikini girls with machine guns,
that stuff will kill ya, & it's loaded with fun,
Bikini girls with machine guns
now they say that virtue is it's own reward,
but when that surf comes in I'm gunna get my board,
I got my own ideas about the righteous kick,
n you can keep the reward, I'd just as soon stay sick...
Bikini girls with machine guns,
Bikini girls with machine guns,
that stuff will kill ya, it's loaded with fun,
Bikini girls with machine guns
>I'm sure that you could put a silicon device in there (suitably re-biased) and
>you'd get the same effect.
No.
Try to create a Rangmaster with Sil, and then with Gem, and you will find
it's 2 other worlds. Also, why do you think the Rangemaster worked so well
with 'rock stars' in the UK, instead of the US, even when enough of them were
available in the US? UK amps with small input/grid resistors hindered the
effect the R/Master's. Hiwatt's (with no resistor) kicked ass with this effect.
Gem devices are (in this day and age) unstable, and need to be matched, as do
all the smart folks know, NTE Gem devices are unstable, and one must go thru 100
to get 6..if you are that lucky. OLD NOS Gem parts are no better, as it's the
nature of the beast, NOT the device. But G devices do 'play' better then S...
There is no Santa Claus on the Midnight Train..
Nor is there any 'fritz' in the RCA future. Idiot me, I dived in that pool again.
..thank God I could swim out with both legs kicking..
JJTj
I've been a drag racer on LSD,
and I rode bare-assed on top of the sphinx,
I even had a gorilla on the slopes of kismet,
and man, that was fun for a while you bet but...
Bikini girls with machine guns,
Bikini girls with machine guns,
that stuff will kill ya, and it's loaded with fun,
Bikini girls with machine guns
well I savored many foriegn kinds of delicacies,
intoxicated til I can't tell what the hell I could see,
had all the violence and liquor within close reach,
but all bars, pills and threeways lead me back to the beach...
...yeah...
Bikini girls with machine guns,
Bikini girls with machine guns,
that stuff will kill ya, & it's loaded with fun,
Bikini girls with machine guns
now they say that virtue is it's own reward,
but when that surf comes in I'm gunna get my board,
I got my own ideas about the righteous kick,
n you can keep the reward, I'd just as soon stay sick...
Bikini girls with machine guns,
Bikini girls with machine guns,
that stuff will kill ya, it's loaded with fun,
Bikini girls with machine guns
Re: Germanium
"Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
news:4825AF43.D4924B73@hotmail . com ...
>
>
> Howard Davis wrote:
>
>> The sound of semiconductor distortion is far more
>> dependent on the specific circuitry the diodes or transistors are used in
>> than on the semiconductor material itself.
>
> Absolutely right.
>
> I suspect what the promoters of 'germanium' circuitry are seeking to
> achieve is
> the sound of old circuit design principles.
>
> I'm sure that you could put a silicon device in there (suitably re-biased)
> and
> you'd get the same effect.
>
> Graham
>
Construct a simple 2 transistor amplifier and add an inverse parallel diodes
to clip the signal in the interstage coupling - then you have a basic fuzz
box, try with both silicon and germanium diodes and feed any convenient
audio signal through it, it will become obvious that the silicon diodes
produce much harsher clipping.
This simple fact is no less true of transistors.
"Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
news:4825AF43.D4924B73@hotmail . com ...
>
>
> Howard Davis wrote:
>
>> The sound of semiconductor distortion is far more
>> dependent on the specific circuitry the diodes or transistors are used in
>> than on the semiconductor material itself.
>
> Absolutely right.
>
> I suspect what the promoters of 'germanium' circuitry are seeking to
> achieve is
> the sound of old circuit design principles.
>
> I'm sure that you could put a silicon device in there (suitably re-biased)
> and
> you'd get the same effect.
>
> Graham
>
Construct a simple 2 transistor amplifier and add an inverse parallel diodes
to clip the signal in the interstage coupling - then you have a basic fuzz
box, try with both silicon and germanium diodes and feed any convenient
audio signal through it, it will become obvious that the silicon diodes
produce much harsher clipping.
This simple fact is no less true of transistors.
Re: Germanium
> Construct a simple 2 transistor amplifier and add an inverse parallel diod=
es
> to clip the signal in the interstage coupling - then you have a basic fuzz=
> box, try with both silicon and germanium diodes and feed any convenient
> audio signal through it, it will become obvious that the silicon diodes
> produce much harsher clipping.
Such test is really not a very good measure of anything. First of all,
it really should also take into account the different forward voltages
that make the Germanium devices clip at much lower signal amplitudes.
Then, if the =93knee=94 is an issue, you can always tweak it with a
suitable series resistor value. So, if one diode has inherently a
softer knee than the other then it really doesn=92t mean a lot in a
complete circuit. Drawing any valid conclusions from a test like this
is difficult at least.
Oh yeah, I think you guys should take a look at:
* w w w .oldradioworld.de/gollum/analysis.htm
I especially dig the figure #4.
> Construct a simple 2 transistor amplifier and add an inverse parallel diod=
es
> to clip the signal in the interstage coupling - then you have a basic fuzz=
> box, try with both silicon and germanium diodes and feed any convenient
> audio signal through it, it will become obvious that the silicon diodes
> produce much harsher clipping.
Such test is really not a very good measure of anything. First of all,
it really should also take into account the different forward voltages
that make the Germanium devices clip at much lower signal amplitudes.
Then, if the =93knee=94 is an issue, you can always tweak it with a
suitable series resistor value. So, if one diode has inherently a
softer knee than the other then it really doesn=92t mean a lot in a
complete circuit. Drawing any valid conclusions from a test like this
is difficult at least.
Oh yeah, I think you guys should take a look at:
* w w w .oldradioworld.de/gollum/analysis.htm
I especially dig the figure #4.
Re: Germanium
<teemukyttala@gmail . com > wrote in message
news:d4061e98-4162-4e95-955b-fe4c005b1f58@c58g2000hsc.googlegroups . com ...
> Construct a simple 2 transistor amplifier and add an inverse parallel
> diodes
> to clip the signal in the interstage coupling - then you have a basic fuzz
> box, try with both silicon and germanium diodes and feed any convenient
> audio signal through it, it will become obvious that the silicon diodes
> produce much harsher clipping.
Such test is really not a very good measure of anything. First of all,
it really should also take into account the different forward voltages
that make the Germanium devices clip at much lower signal amplitudes.
Then, if the “knee” is an issue, you can always tweak it with a
suitable series resistor value. So, if one diode has inherently a
softer knee than the other then it really doesn’t mean a lot in a
complete circuit. Drawing any valid conclusions from a test like this
is difficult at least.
Oh yeah, I think you guys should take a look at:
* w w w .oldradioworld.de/gollum/analysis.htm
I especially dig the figure #4.
.........where its clearly seen that the germanium device has a much
shallower knee curve than any other device.
<teemukyttala@gmail . com > wrote in message
news:d4061e98-4162-4e95-955b-fe4c005b1f58@c58g2000hsc.googlegroups . com ...
> Construct a simple 2 transistor amplifier and add an inverse parallel
> diodes
> to clip the signal in the interstage coupling - then you have a basic fuzz
> box, try with both silicon and germanium diodes and feed any convenient
> audio signal through it, it will become obvious that the silicon diodes
> produce much harsher clipping.
Such test is really not a very good measure of anything. First of all,
it really should also take into account the different forward voltages
that make the Germanium devices clip at much lower signal amplitudes.
Then, if the “knee” is an issue, you can always tweak it with a
suitable series resistor value. So, if one diode has inherently a
softer knee than the other then it really doesn’t mean a lot in a
complete circuit. Drawing any valid conclusions from a test like this
is difficult at least.
Oh yeah, I think you guys should take a look at:
* w w w .oldradioworld.de/gollum/analysis.htm
I especially dig the figure #4.
.........where its clearly seen that the germanium device has a much
shallower knee curve than any other device.
Re: Germanium
> .........where its clearly seen that the germanium device has a much
> shallower knee curve than any other device.
That=92s why I posted the figure in the first place. Yet, while the
curves are generally shallower in Germanium devices the figure also
shows that there is a huge variation in that characteristic. For
example, BAT33 (Si Schottky?) is pretty much the same as 1N34A (Ge).
=46rom the two extremes, AA112 (Ge) is a very distinctive example along
with 1N914 (Si).
I still fail to see how the test setup you described takes account of
different forward voltages, device variations (whether they=92re Ge or
Si) and the effect of source impedance.
> .........where its clearly seen that the germanium device has a much
> shallower knee curve than any other device.
That=92s why I posted the figure in the first place. Yet, while the
curves are generally shallower in Germanium devices the figure also
shows that there is a huge variation in that characteristic. For
example, BAT33 (Si Schottky?) is pretty much the same as 1N34A (Ge).
=46rom the two extremes, AA112 (Ge) is a very distinctive example along
with 1N914 (Si).
I still fail to see how the test setup you described takes account of
different forward voltages, device variations (whether they=92re Ge or
Si) and the effect of source impedance.
Re: Germanium
<teemukyttala@gmail . com > wrote in message
news:f3b44e90-2958-43ce-9754-5da6b4e60c44@t54g2000hsg.googlegroups . com ...
> .........where its clearly seen that the germanium device has a much
> shallower knee curve than any other device.
That’s why I posted the figure in the first place. Yet, while the
curves are generally shallower in Germanium devices the figure also
shows that there is a huge variation in that characteristic. For
example, BAT33 (Si Schottky?) is pretty much the same as 1N34A (Ge).
From the two extremes, AA112 (Ge) is a very distinctive example along
with 1N914 (Si).
I still fail to see how the test setup you described takes account of
different forward voltages, device variations (whether they’re Ge or
Si) and the effect of source impedance.
The difference in forward voltage is more significant than many people
realise at the small amplitudes from a pickup but even the basic setup I
suggested which would probably be evaluated at a higher signal level, the
harsh clipping of silicon would be distinguishable from the more progressive
onset with germanium.
<teemukyttala@gmail . com > wrote in message
news:f3b44e90-2958-43ce-9754-5da6b4e60c44@t54g2000hsg.googlegroups . com ...
> .........where its clearly seen that the germanium device has a much
> shallower knee curve than any other device.
That’s why I posted the figure in the first place. Yet, while the
curves are generally shallower in Germanium devices the figure also
shows that there is a huge variation in that characteristic. For
example, BAT33 (Si Schottky?) is pretty much the same as 1N34A (Ge).
From the two extremes, AA112 (Ge) is a very distinctive example along
with 1N914 (Si).
I still fail to see how the test setup you described takes account of
different forward voltages, device variations (whether they’re Ge or
Si) and the effect of source impedance.
The difference in forward voltage is more significant than many people
realise at the small amplitudes from a pickup but even the basic setup I
suggested which would probably be evaluated at a higher signal level, the
harsh clipping of silicon would be distinguishable from the more progressive
onset with germanium.
Re: Germanium
<teemukyttala@gmail . com > wrote
...
> Oh yeah, I think you guys should take a look at:
>
> * w w w .oldradioworld.de/gollum/analysis.htm
>
> I especially dig the figure #4.
I want cat's whiskers in my next fuzz box! Check out
the galena curves...
__
Steve
.
<teemukyttala@gmail . com > wrote
...
> Oh yeah, I think you guys should take a look at:
>
> * w w w .oldradioworld.de/gollum/analysis.htm
>
> I especially dig the figure #4.
I want cat's whiskers in my next fuzz box! Check out
the galena curves...
__
Steve
.
Re: Germanium
"ian field" <dai.ode@ntlworld . com > wrote in message
news:4mmVj.3255$JK4.989@newsfe30.ams2...
>
> "Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
> news:4825AF43.D4924B73@hotmail . com ...
>>
>> Howard Davis wrote:
>>
>>> The sound of semiconductor distortion is far more
>>> dependent on the specific circuitry the diodes or transistors are used
>>> in
>>> than on the semiconductor material itself.
>>
>> Absolutely right.
>
>> I suspect what the promoters of 'germanium' circuitry are seeking to
>> achieve is the sound of old circuit design principles.
>>
>> I'm sure that you could put a silicon device in there (suitably
>> re-biased) and you'd get the same effect.
>>
>> Graham
> Construct a simple 2 transistor amplifier and add an inverse parallel
> diodes to clip the signal in the interstage coupling - then you have a
> basic fuzz box, try with both silicon and germanium diodes and feed any
> convenient audio signal through it, it will become obvious that the
> silicon diodes produce much harsher clipping.
>
> This simple fact is no less true of transistors.
--------------
The scientifically proper test is to compare (a/b) two otherwise identical
circuits using the same power supply and the same signal feeding both.
Assume the number of diodes in these "fuzzbox" test circuits are the same,
as is everything else, except for the type of semiconductor the diodes are
made from. The resulting amplified clipped waveform using the silicon diodes
will be over 6db higher in level than with the germanium diodes, and this is
the source of the resulting relative harshness. The output waveforms will be
identical or almost so, with VERY little if any audible difference, when the
output levels are adjusted to be equal. This of course assumes the design
allows the output stage to operate linearly, and not introduce additional
clipping due to the higher level of the silicon diode's clipped waveform.
Howard Davis, EE
Guitar pedal design engineering, repairs, and custom mods:
* howard.davis2.home.att . net /
"ian field" <dai.ode@ntlworld . com > wrote in message
news:4mmVj.3255$JK4.989@newsfe30.ams2...
>
> "Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
> news:4825AF43.D4924B73@hotmail . com ...
>>
>> Howard Davis wrote:
>>
>>> The sound of semiconductor distortion is far more
>>> dependent on the specific circuitry the diodes or transistors are used
>>> in
>>> than on the semiconductor material itself.
>>
>> Absolutely right.
>
>> I suspect what the promoters of 'germanium' circuitry are seeking to
>> achieve is the sound of old circuit design principles.
>>
>> I'm sure that you could put a silicon device in there (suitably
>> re-biased) and you'd get the same effect.
>>
>> Graham
> Construct a simple 2 transistor amplifier and add an inverse parallel
> diodes to clip the signal in the interstage coupling - then you have a
> basic fuzz box, try with both silicon and germanium diodes and feed any
> convenient audio signal through it, it will become obvious that the
> silicon diodes produce much harsher clipping.
>
> This simple fact is no less true of transistors.
--------------
The scientifically proper test is to compare (a/b) two otherwise identical
circuits using the same power supply and the same signal feeding both.
Assume the number of diodes in these "fuzzbox" test circuits are the same,
as is everything else, except for the type of semiconductor the diodes are
made from. The resulting amplified clipped waveform using the silicon diodes
will be over 6db higher in level than with the germanium diodes, and this is
the source of the resulting relative harshness. The output waveforms will be
identical or almost so, with VERY little if any audible difference, when the
output levels are adjusted to be equal. This of course assumes the design
allows the output stage to operate linearly, and not introduce additional
clipping due to the higher level of the silicon diode's clipped waveform.
Howard Davis, EE
Guitar pedal design engineering, repairs, and custom mods:
* howard.davis2.home.att . net /
Re: Germanium
"Howard Davis" <howard@worldnet.att . net > wrote in message
news:MynVj.185490$D_3.53777@bgtnsc05-news.ops.worldnet.att . net ...
> "ian field" <dai.ode@ntlworld . com > wrote in message
> news:4mmVj.3255$JK4.989@newsfe30.ams2...
>>
>> "Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
>> news:4825AF43.D4924B73@hotmail . com ...
>>>
>>> Howard Davis wrote:
>>>
>>>> The sound of semiconductor distortion is far more
>>>> dependent on the specific circuitry the diodes or transistors are used
>>>> in
>>>> than on the semiconductor material itself.
>>>
>>> Absolutely right.
>>
>>> I suspect what the promoters of 'germanium' circuitry are seeking to
>>> achieve is the sound of old circuit design principles.
>>>
>>> I'm sure that you could put a silicon device in there (suitably
>>> re-biased) and you'd get the same effect.
>>>
>>> Graham
>
>> Construct a simple 2 transistor amplifier and add an inverse parallel
>> diodes to clip the signal in the interstage coupling - then you have a
>> basic fuzz box, try with both silicon and germanium diodes and feed any
>> convenient audio signal through it, it will become obvious that the
>> silicon diodes produce much harsher clipping.
>>
>> This simple fact is no less true of transistors.
>
> --------------
> The scientifically proper test is to compare (a/b) two otherwise identical
> circuits using the same power supply and the same signal feeding both.
> Assume the number of diodes in these "fuzzbox" test circuits are the same,
> as is everything else, except for the type of semiconductor the diodes are
> made from. The resulting amplified clipped waveform using the silicon
> diodes will be over 6db higher in level than with the germanium diodes,
> and this is the source of the resulting relative harshness. The output
> waveforms will be identical or almost so, with VERY little if any audible
> difference, when the output levels are adjusted to be equal. This of
> course assumes the design allows the output stage to operate linearly, and
> not introduce additional clipping due to the higher level of the silicon
> diode's clipped waveform.
>
> Howard Davis, EE
> Guitar pedal design engineering, repairs, and custom mods:
> * howard.davis2.home.att . net /
>
>
I can't believe that devices with conspicuously different knee curves don't
produce different tone, but I do believe the evidence of my own ears.
"Howard Davis" <howard@worldnet.att . net > wrote in message
news:MynVj.185490$D_3.53777@bgtnsc05-news.ops.worldnet.att . net ...
> "ian field" <dai.ode@ntlworld . com > wrote in message
> news:4mmVj.3255$JK4.989@newsfe30.ams2...
>>
>> "Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
>> news:4825AF43.D4924B73@hotmail . com ...
>>>
>>> Howard Davis wrote:
>>>
>>>> The sound of semiconductor distortion is far more
>>>> dependent on the specific circuitry the diodes or transistors are used
>>>> in
>>>> than on the semiconductor material itself.
>>>
>>> Absolutely right.
>>
>>> I suspect what the promoters of 'germanium' circuitry are seeking to
>>> achieve is the sound of old circuit design principles.
>>>
>>> I'm sure that you could put a silicon device in there (suitably
>>> re-biased) and you'd get the same effect.
>>>
>>> Graham
>
>> Construct a simple 2 transistor amplifier and add an inverse parallel
>> diodes to clip the signal in the interstage coupling - then you have a
>> basic fuzz box, try with both silicon and germanium diodes and feed any
>> convenient audio signal through it, it will become obvious that the
>> silicon diodes produce much harsher clipping.
>>
>> This simple fact is no less true of transistors.
>
> --------------
> The scientifically proper test is to compare (a/b) two otherwise identical
> circuits using the same power supply and the same signal feeding both.
> Assume the number of diodes in these "fuzzbox" test circuits are the same,
> as is everything else, except for the type of semiconductor the diodes are
> made from. The resulting amplified clipped waveform using the silicon
> diodes will be over 6db higher in level than with the germanium diodes,
> and this is the source of the resulting relative harshness. The output
> waveforms will be identical or almost so, with VERY little if any audible
> difference, when the output levels are adjusted to be equal. This of
> course assumes the design allows the output stage to operate linearly, and
> not introduce additional clipping due to the higher level of the silicon
> diode's clipped waveform.
>
> Howard Davis, EE
> Guitar pedal design engineering, repairs, and custom mods:
> * howard.davis2.home.att . net /
>
>
I can't believe that devices with conspicuously different knee curves don't
produce different tone, but I do believe the evidence of my own ears.
Re: Germanium
"ian field" <dai.ode@ntlworld . com > wrote in message
news:_6pVj.37612$6a2.20195@newsfe17.ams2...
>
> "Howard Davis" <howard@worldnet.att . net > wrote in message
> news:MynVj.185490$D_3.53777@bgtnsc05-news.ops.worldnet.att . net ...
>> "ian field" <dai.ode@ntlworld . com > wrote in message
>> news:4mmVj.3255$JK4.989@newsfe30.ams2...
>>>
>>> "Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
>>> news:4825AF43.D4924B73@hotmail . com ...
>>>>
>>>> Howard Davis wrote:
>>>>
>>>>> The sound of semiconductor distortion is far more
>>>>> dependent on the specific circuitry the diodes or transistors are used
>>>>> in
>>>>> than on the semiconductor material itself.
>>>>
>>>> Absolutely right.
>>>
>>>> I suspect what the promoters of 'germanium' circuitry are seeking to
>>>> achieve is the sound of old circuit design principles.
>>>>
>>>> I'm sure that you could put a silicon device in there (suitably
>>>> re-biased) and you'd get the same effect.
>>>>
>>>> Graham
>>
>>> Construct a simple 2 transistor amplifier and add an inverse parallel
>>> diodes to clip the signal in the interstage coupling - then you have a
>>> basic fuzz box, try with both silicon and germanium diodes and feed any
>>> convenient audio signal through it, it will become obvious that the
>>> silicon diodes produce much harsher clipping.
>>>
>>> This simple fact is no less true of transistors.
>>
>> --------------
>> The scientifically proper test is to compare (a/b) two otherwise
>> identical circuits using the same power supply and the same signal
>> feeding both. Assume the number of diodes in these "fuzzbox" test
>> circuits are the same, as is everything else, except for the type of
>> semiconductor the diodes are made from. The resulting amplified clipped
>> waveform using the silicon diodes will be over 6db higher in level than
>> with the germanium diodes, and this is the source of the resulting
>> relative harshness. The output waveforms will be identical or almost so,
>> with VERY little if any audible difference, when the output levels are
>> adjusted to be equal. This of course assumes the design allows the output
>> stage to operate linearly, and not introduce additional clipping due to
>> the higher level of the silicon diode's clipped waveform.
>>
>> Howard Davis, EE
>> Guitar pedal design engineering, repairs, and custom mods:
>> * howard.davis2.home.att . net /
> I can't believe that devices with conspicuously different knee curves
> don't produce different tone, but I do believe the evidence of my own
> ears.
I have a textbook I used when taking an undergrad electronics course at
Cooper Union. In the section on semiconductors, it shows curves for both the
silicon and germanium PN junctions on the same current-voltage axes. They
are identical in shape, but the silicon curve is shifted to the right by the
greater forward voltage drop of silicon. The math of semiconductor physics
theory confirms this.
Other than this difference in forward voltage, the amount of resistance in
series with the diode(s) in the circuit make a far greater difference in the
"softness" of the knee of the curve of the entire circuit, than the type of
semiconductor diode used.
The CIRCUITRY, far more than the semiconductor type used in it, determines
differences in audible tone characteristics. Thus, as in the DISNORTION and
POLYSATURATOR pedals I designed for Pigtronix, you can make silicon-based
semiconductor circuitry sound "tubier than tubes."
Howard Davis, EE
Guitar pedal design engineering, repairs, and custom mods:
* howard.davis2.home.att . net /
"ian field" <dai.ode@ntlworld . com > wrote in message
news:_6pVj.37612$6a2.20195@newsfe17.ams2...
>
> "Howard Davis" <howard@worldnet.att . net > wrote in message
> news:MynVj.185490$D_3.53777@bgtnsc05-news.ops.worldnet.att . net ...
>> "ian field" <dai.ode@ntlworld . com > wrote in message
>> news:4mmVj.3255$JK4.989@newsfe30.ams2...
>>>
>>> "Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
>>> news:4825AF43.D4924B73@hotmail . com ...
>>>>
>>>> Howard Davis wrote:
>>>>
>>>>> The sound of semiconductor distortion is far more
>>>>> dependent on the specific circuitry the diodes or transistors are used
>>>>> in
>>>>> than on the semiconductor material itself.
>>>>
>>>> Absolutely right.
>>>
>>>> I suspect what the promoters of 'germanium' circuitry are seeking to
>>>> achieve is the sound of old circuit design principles.
>>>>
>>>> I'm sure that you could put a silicon device in there (suitably
>>>> re-biased) and you'd get the same effect.
>>>>
>>>> Graham
>>
>>> Construct a simple 2 transistor amplifier and add an inverse parallel
>>> diodes to clip the signal in the interstage coupling - then you have a
>>> basic fuzz box, try with both silicon and germanium diodes and feed any
>>> convenient audio signal through it, it will become obvious that the
>>> silicon diodes produce much harsher clipping.
>>>
>>> This simple fact is no less true of transistors.
>>
>> --------------
>> The scientifically proper test is to compare (a/b) two otherwise
>> identical circuits using the same power supply and the same signal
>> feeding both. Assume the number of diodes in these "fuzzbox" test
>> circuits are the same, as is everything else, except for the type of
>> semiconductor the diodes are made from. The resulting amplified clipped
>> waveform using the silicon diodes will be over 6db higher in level than
>> with the germanium diodes, and this is the source of the resulting
>> relative harshness. The output waveforms will be identical or almost so,
>> with VERY little if any audible difference, when the output levels are
>> adjusted to be equal. This of course assumes the design allows the output
>> stage to operate linearly, and not introduce additional clipping due to
>> the higher level of the silicon diode's clipped waveform.
>>
>> Howard Davis, EE
>> Guitar pedal design engineering, repairs, and custom mods:
>> * howard.davis2.home.att . net /
> I can't believe that devices with conspicuously different knee curves
> don't produce different tone, but I do believe the evidence of my own
> ears.
I have a textbook I used when taking an undergrad electronics course at
Cooper Union. In the section on semiconductors, it shows curves for both the
silicon and germanium PN junctions on the same current-voltage axes. They
are identical in shape, but the silicon curve is shifted to the right by the
greater forward voltage drop of silicon. The math of semiconductor physics
theory confirms this.
Other than this difference in forward voltage, the amount of resistance in
series with the diode(s) in the circuit make a far greater difference in the
"softness" of the knee of the curve of the entire circuit, than the type of
semiconductor diode used.
The CIRCUITRY, far more than the semiconductor type used in it, determines
differences in audible tone characteristics. Thus, as in the DISNORTION and
POLYSATURATOR pedals I designed for Pigtronix, you can make silicon-based
semiconductor circuitry sound "tubier than tubes."
Howard Davis, EE
Guitar pedal design engineering, repairs, and custom mods:
* howard.davis2.home.att . net /
Re: Germanium
Howard Davis wrote:
> "ian field" <dai.ode@ntlworld . com > wrote in message
> news: 6pVj.37612$6a2.20195@newsfe17.ams2...
>> "Howard Davis" <howard@worldnet.att . net > wrote in message
>> news:MynVj.185490$D 3.53777@bgtnsc05-news.ops.worldnet.att . net ...
>>> "ian field" <dai.ode@ntlworld . com > wrote in message
>>> news:4mmVj.3255$JK4.989@newsfe30.ams2...
>>>> "Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
>>>> news:4825AF43.D4924B73@hotmail . com ...
>>>>> Howard Davis wrote:
>>>>>
>>>>>> The sound of semiconductor distortion is far more
>>>>>> dependent on the specific circuitry the diodes or transistors are used
>>>>>> in
>>>>>> than on the semiconductor material itself.
>>>>> Absolutely right.
>>>>> I suspect what the promoters of 'germanium' circuitry are seeking to
>>>>> achieve is the sound of old circuit design principles.
>>>>>
>>>>> I'm sure that you could put a silicon device in there (suitably
>>>>> re-biased) and you'd get the same effect.
>>>>>
>>>>> Graham
>>>> Construct a simple 2 transistor amplifier and add an inverse parallel
>>>> diodes to clip the signal in the interstage coupling - then you have a
>>>> basic fuzz box, try with both silicon and germanium diodes and feed any
>>>> convenient audio signal through it, it will become obvious that the
>>>> silicon diodes produce much harsher clipping.
>>>>
>>>> This simple fact is no less true of transistors.
>>> --------------
>>> The scientifically proper test is to compare (a/b) two otherwise
>>> identical circuits using the same power supply and the same signal
>>> feeding both. Assume the number of diodes in these "fuzzbox" test
>>> circuits are the same, as is everything else, except for the type of
>>> semiconductor the diodes are made from. The resulting amplified clipped
>>> waveform using the silicon diodes will be over 6db higher in level than
>>> with the germanium diodes, and this is the source of the resulting
>>> relative harshness. The output waveforms will be identical or almost so,
>>> with VERY little if any audible difference, when the output levels are
>>> adjusted to be equal. This of course assumes the design allows the output
>>> stage to operate linearly, and not introduce additional clipping due to
>>> the higher level of the silicon diode's clipped waveform.
>>>
>>> Howard Davis, EE
>>> Guitar pedal design engineering, repairs, and custom mods:
>>> * howard.davis2.home.att . net /
>
>> I can't believe that devices with conspicuously different knee curves
>> don't produce different tone, but I do believe the evidence of my own
>> ears.
>
> I have a textbook I used when taking an undergrad electronics course at
> Cooper Union. In the section on semiconductors, it shows curves for both the
> silicon and germanium PN junctions on the same current-voltage axes. They
> are identical in shape, but the silicon curve is shifted to the right by the
> greater forward voltage drop of silicon. The math of semiconductor physics
> theory confirms this.
>
> Other than this difference in forward voltage, the amount of resistance in
> series with the diode(s) in the circuit make a far greater difference in the
> "softness" of the knee of the curve of the entire circuit, than the type of
> semiconductor diode used.
>
> The CIRCUITRY, far more than the semiconductor type used in it, determines
> differences in audible tone characteristics. Thus, as in the DISNORTION and
> POLYSATURATOR pedals I designed for Pigtronix, you can make silicon-based
> semiconductor circuitry sound "tubier than tubes."
>
> Howard Davis, EE
> Guitar pedal design engineering, repairs, and custom mods:
> * howard.davis2.home.att . net /
>
>
I'm not a tech but you've made this abundantly clear. It's the circuitry
design, not the semiconductor type, that makes the substantiative
difference. Thanks. mvm
Howard Davis wrote:
> "ian field" <dai.ode@ntlworld . com > wrote in message
> news: 6pVj.37612$6a2.20195@newsfe17.ams2...
>> "Howard Davis" <howard@worldnet.att . net > wrote in message
>> news:MynVj.185490$D 3.53777@bgtnsc05-news.ops.worldnet.att . net ...
>>> "ian field" <dai.ode@ntlworld . com > wrote in message
>>> news:4mmVj.3255$JK4.989@newsfe30.ams2...
>>>> "Eeyore" <rabbitsfriendsandrelations@hotmail . com > wrote in message
>>>> news:4825AF43.D4924B73@hotmail . com ...
>>>>> Howard Davis wrote:
>>>>>
>>>>>> The sound of semiconductor distortion is far more
>>>>>> dependent on the specific circuitry the diodes or transistors are used
>>>>>> in
>>>>>> than on the semiconductor material itself.
>>>>> Absolutely right.
>>>>> I suspect what the promoters of 'germanium' circuitry are seeking to
>>>>> achieve is the sound of old circuit design principles.
>>>>>
>>>>> I'm sure that you could put a silicon device in there (suitably
>>>>> re-biased) and you'd get the same effect.
>>>>>
>>>>> Graham
>>>> Construct a simple 2 transistor amplifier and add an inverse parallel
>>>> diodes to clip the signal in the interstage coupling - then you have a
>>>> basic fuzz box, try with both silicon and germanium diodes and feed any
>>>> convenient audio signal through it, it will become obvious that the
>>>> silicon diodes produce much harsher clipping.
>>>>
>>>> This simple fact is no less true of transistors.
>>> --------------
>>> The scientifically proper test is to compare (a/b) two otherwise
>>> identical circuits using the same power supply and the same signal
>>> feeding both. Assume the number of diodes in these "fuzzbox" test
>>> circuits are the same, as is everything else, except for the type of
>>> semiconductor the diodes are made from. The resulting amplified clipped
>>> waveform using the silicon diodes will be over 6db higher in level than
>>> with the germanium diodes, and this is the source of the resulting
>>> relative harshness. The output waveforms will be identical or almost so,
>>> with VERY little if any audible difference, when the output levels are
>>> adjusted to be equal. This of course assumes the design allows the output
>>> stage to operate linearly, and not introduce additional clipping due to
>>> the higher level of the silicon diode's clipped waveform.
>>>
>>> Howard Davis, EE
>>> Guitar pedal design engineering, repairs, and custom mods:
>>> * howard.davis2.home.att . net /
>
>> I can't believe that devices with conspicuously different knee curves
>> don't produce different tone, but I do believe the evidence of my own
>> ears.
>
> I have a textbook I used when taking an undergrad electronics course at
> Cooper Union. In the section on semiconductors, it shows curves for both the
> silicon and germanium PN junctions on the same current-voltage axes. They
> are identical in shape, but the silicon curve is shifted to the right by the
> greater forward voltage drop of silicon. The math of semiconductor physics
> theory confirms this.
>
> Other than this difference in forward voltage, the amount of resistance in
> series with the diode(s) in the circuit make a far greater difference in the
> "softness" of the knee of the curve of the entire circuit, than the type of
> semiconductor diode used.
>
> The CIRCUITRY, far more than the semiconductor type used in it, determines
> differences in audible tone characteristics. Thus, as in the DISNORTION and
> POLYSATURATOR pedals I designed for Pigtronix, you can make silicon-based
> semiconductor circuitry sound "tubier than tubes."
>
> Howard Davis, EE
> Guitar pedal design engineering, repairs, and custom mods:
> * howard.davis2.home.att . net /
>
>
I'm not a tech but you've made this abundantly clear. It's the circuitry
design, not the semiconductor type, that makes the substantiative
difference. Thanks. mvm
Re: Germanium
ian field wrote:
> try with both silicon and germanium diodes and feed any convenient
> audio signal through it, it will become obvious that the silicon diodes
> produce much harsher clipping.
Because a germanium diode is likely to be a point contact type and a silicon
diode is likely to be a junction type.
That's the same as comparing chalk and cheese. What's the point of that ?
Compare silicon and germanium point contact diodes and I'll bet the result's
quite different and they'll sound similar, although of course, the higher Vf of
silicon means it will do its thing at a slightly higher signal level.
Why is it that people love to change ALL the parematers and then announce it's
different ? Of course it will be.
You have to compare like with like.
Since silicon point contact diodes are very rare (radar detectors like the 1N23)
you could simulate one by adding some forward series resistance (330 ohms ?) and
a higher value parallel resistance (3300 ohms ?) to a 1N4148 perhaps.
Graham
ian field wrote:
> try with both silicon and germanium diodes and feed any convenient
> audio signal through it, it will become obvious that the silicon diodes
> produce much harsher clipping.
Because a germanium diode is likely to be a point contact type and a silicon
diode is likely to be a junction type.
That's the same as comparing chalk and cheese. What's the point of that ?
Compare silicon and germanium point contact diodes and I'll bet the result's
quite different and they'll sound similar, although of course, the higher Vf of
silicon means it will do its thing at a slightly higher signal level.
Why is it that people love to change ALL the parematers and then announce it's
different ? Of course it will be.
You have to compare like with like.
Since silicon point contact diodes are very rare (radar detectors like the 1N23)
you could simulate one by adding some forward series resistance (330 ohms ?) and
a higher value parallel resistance (3300 ohms ?) to a 1N4148 perhaps.
Graham
