A good motivation for going wireless. I can change instruments between songs without a noise, without muting anything.Gene Pink said:1) Instrument changes between songs.
A good motivation for going wireless. I can change instruments between songs without a noise, without muting anything.Gene Pink said:1) Instrument changes between songs.
Indeed, but changing instruments in the studio is not an issue, is it?Tubetec said:in a studio situation Id strongly discourage any kind of wireless transmission at least on the input signal path
I don't worry about it anymore; I've modified most of my amps with an NTP in series with the primary.Tubetec said:the extra poles on the switch can be used for a limiting/inrush/bleed resistor too , as pointed out by JR .
abbey road d enfer said:I don't worry about it anymore; I've modified most of my amps with an NTP in series with the primary.
Just the fraction of second it takes to damp the inrush caused by the magnetizing current of the magnetic core and capacitor charging. Definitely not the kind of slow ramping some are advocating.Tubetec said:I can see the logic of the NTP in the primary from the point of view heater inrush at switch on ,but does it also hold back HT and if so what sort of ramp up times do they allow ?
When properly dimensioned, the voltage drop caused by the NTC's resistance will be about 1V at full load. Not significant.I can see how a correctly chosen component could give extra overall protection to a tube amp that develops a fault ,but I do wonder if it might effect the dynamics to some degree under hard rock output drive conditions .
gyraf said:..and the idea is only really usable for high-power tubes (power amplifiers, RF transmitters)..
Jakob E.
Many Fender amps e.g. this onejohnheath said:May I ask if we could see a schematic of this input stage of yours?
abbey road d enfer said:Many Fender amps e.g. this one
https://fr.scribd.com/doc/123978870/Fender-Blues-Deluxe-Service-Manual
The thermistor is rated at 10 ohms; that's the nominal resistance at ambient temperature. As soon as current goes through, the thermistor heats up and its resistance decreases drastically, to a fraction of ohm.
But there will not be a current surge to charge already charged capacitors, etc.saint gillis said:Only "problem" is if the amp is switched off and immediately on again, then the thermistor is still hot and does not act.. right?
It all depends on the sequence of events; as JR mentioned, if the caps have not yet discharged, there is only the magnetizing current surge. The time constant of the commonly used NTC's is a few dozen of seconds. Clearly there is a possibility that switching back on appears before the NTC has gone back to nominal (ambient) resistance. Such a simple implement cannot be 100% foolproof.saint gillis said:Only "problem" is if the amp is switched off and immediately on again, then the thermistor is still hot and does not act.. right?
abbey road d enfer said:Many Fender amps e.g. this one
https://fr.scribd.com/doc/123978870/Fender-Blues-Deluxe-Service-Manual
The thermistor is rated at 10 ohms; that's the nominal resistance at ambient temperature. As soon as current goes through, the thermistor heats up and its resistance decreases drastically, to a fraction of ohm.
abbey road d enfer said:It all depends on the sequence of events; as JR mentioned, if the caps have not yet discharged, there is only the magnetizing current surge. The time constant of the commonly used NTC's is a few dozen of seconds. Clearly there is a possibility that switching back on appears before the NTC has gone back to nominal (ambient) resistance. Such a simple implement cannot be 100% foolproof.
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