I read somewhere that you Mark, Dave and others prefer an ECC81 on Pi Stage instead of ECC83 but I don't really know why ?
My understanding is that with a ECC83 (12AX7), the power stage is pushed harder so the headroom is decreased and breakup comes earlier but is that the "only" effect ? Is it really noticeable ?
Can I summarize like this : If I got a Les Paul and wants more crunch with less volume (What do you say ? Whaaaat ?! ), I would prefer a ECC83 but if I want to use plenty of pedals and so want highest headroom then I go for ECC81 ?
billou_35 wrote:
Can I summarize like this : If I got a Les Paul and wants more crunch with less volume (What do you say ? Whaaaat ?! ), I would prefer a ECC83 but if I want to use plenty of pedals and so want highest headroom then I go for ECC81 ?
That's about it.
Your particular HIWATT and tubes may interact differently. Let your ears be your guide.
billou_35 wrote:My understanding is that with a ECC83 (12AX7), the power stage is pushed harder so the headroom is decreased and breakup comes earlier
The ECC83 has a lower anode current (1.2mA) compared with the ECC81 (10mA).
An ECC83 in the phase inverter position will give you more breakup due to its higher gain factor (100 vs. 60) but I believe it actually pushes the power section LESS hard than an ECC81.
I prefer the ECC81 - bigger, bolder, more headroom. If I want more preamp breakup I'll boost the front end a bit.
You can almost feel the current flowing
You can almost see the circuits blowing
billou_35 wrote:My understanding is that with a ECC83 (12AX7), the power stage is pushed harder so the headroom is decreased and breakup comes earlier
The ECC83 has a lower anode current (1.2mA) compared with the ECC81 (10mA).
An ECC83 in the phase inverter position will give you more breakup due to its higher gain factor (100 vs. 60) but I believe it actually pushes the power section LESS hard than an ECC81.
I prefer the ECC81 - bigger, bolder, more headroom. If I want more preamp breakup I'll boost the front end a bit.