Analog Tube Power amp simulator: studying possibilities
- Thread starter cris_mas
- Start date
temol
Well-known member
What's the signal level at the preamp output? Do you have an oscilloscope? Or some other way to measure signal amplitude? What kind of preamp is it? If it's simply a 1:1 tube amplifier with only volume after EQ, and it's running at 300V, you'll easily have a few volts p/p. The Reactor only has a 9V power supply, so you'll need to severely limit the input signal to avoid heavy clipping and overloading.
Paradox916
Well-known member
Now I’m going to catch some heat for this and that’s alright.. but did you ever consider it’s not the power amp you are frustrated with and its the speaker and cab?
Do you mean at the soundcard input? I'm using my SSL 2+ Hi-Z input...and the signal inside Logic looks ok. When I use the preamp without the Reactor there's no problem. I don't think the problem is there but thanks for your input
I think you're on the right track there, Temol. I have a scope so I'll do some readings and report back. Thanks for the ideas
Ok, I'm not frustrated with the sound. It actually sounds great and comes SOMEHOW close to my ´67 Bassman (seriously!).
So the problem is not how it sounds but that it seems to "choke" in some circumstances, when trying to "push" the circuit. I'm pretty sure that what Temol pointed out is the culprit so I'm going to plug my scope in and see what's going on in there and report back
Thanks to everybody for all your ideas and help!
Cheers
Sono
A reamp device as I understand brings the linelevel from a DAW down to instrument level in order to be able to feed it to an amp.
The reamp device in this case would be between preamp and the reactor to bring the preamplevel down to instrument level(reactor)
The reamp device in this case would be between preamp and the reactor to bring the preamplevel down to instrument level(reactor)
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Thanks for the suggestion Einzeln, but I'm not entirely sure I'd need that. The preamp also has a jack output which is supposed to go into a poweramp, so I THINK that's High Impedance. If so, that would match instrument level wouldn't it?
If I understand correctly, that reamp device you mention would work like an "impedance converter", right?
Cheers
Sono
Wouldn't a reamper use a transformer to "convert" the signal?
Hi again,
I've had to delay this for a while but now I'm back
Ok, so where would you sugest I place the scope? At the Reactor input for instance to check if the preamp output signal is clipping/overloading the Reactor and eventually adjust the preamp output accordingly? Or maybe one channel at the Reactor input and the other at the Presence control output?
Cheers
Sono
temol
Well-known member
Output of the preamp. output of the Reactor.Hi again,
I've had to delay this for a while but now I'm back
Ok, so where would you sugest I place the scope? At the Reactor input for instance to check if the preamp output signal is clipping/overloading the Reactor and eventually adjust the preamp output accordingly? Or maybe one channel at the Reactor input and the other at the Presence control output?
Cheers
Sono
Quote from the thread on freestompboxes: "Ideally the input drive is set low and the output level is set to maximum to obtain the clearest possible signal output, however increasing the drive and decreasing the output level can cause the clipping diodes to conduct especially on maximum presence control settings."
But even low may not be enough for a very large input signal.
You're not going to believe this: I plugged everything again together before hooking up the scope and now everything was fine...I was scratching my head trying to figure out what had changed and then I saw it! I had hooked by mistake the Reactor BEFORE the tube preamp!! Now the tube preamp wasn't overloading the reactor. And the sound was great! So I tried putting an overdrive pedal before the Reactor to see how it would behave and it sounds KILLER!!!
So, just to clarify, the order for everything to sound great is Guitar -> Fx pedals -> Reactor -> Tube Preamp -> Speaker Emu -> mixer/PA/soundcard Hi-Z input (or D.I.)
Now there's no choking at all no matter how hard you hit the strings, when cranking up the Reactor Drive you can hear some "poweramp distortion", the Presence pot works really well and all the controls on each device actually does something noticeable. At good volume the feeling is VERY SIMILAR to a real amp.
Thanks a lot for all your help and ideas guys!!
Cheers
Sono
You mean fx pedals-tube pre-
Reactor
No, that's the way I hooked it before (it's the expected logical way). Then I hooked it by mistake guitar -> pedal fx -> reactor -> tube preamp -> speak sim -> soundcard/mixer and it sounds great....
I think it works because the Reactor isn't really a poweramp but more like an emulation of how a tube poweramp output behaves and what it adds sonically....