VC508_Line_Out_Without_Speaker_Kill

[hewo]

Thank you kleuck for your responses

I'm not sure active circuitry can be considered superior, depends on you goals.
Theoretically, you can achieve a more precise simulation of a given speaker, but i do not agree.
What are actually achieving most active simulators ? They try to emulate the speaker's frequency response, fine.But it's a poor way to simulate a speaker imo, because
1) Curves are drawn with a 1 watt signal, are you under the impression that your speaker sounds the same under 1 watt or under 25 ? That's not the case with our tube amps with very low -if any- damping factor.
2) I own two very different sounding speakers, though the curves are (almost) exactly the same, minus the efficiency, so what the fuck ?
3) You will need a Xformer anyway to achieve ground-lift.
So, for me, active sims are way to complicated for a not-so-perfect result.
Added to that, for a good result, you will need more than a TL072 i think, most simulators are using a quad aop or two dual (see Marshalls, or the condor sim) the only simpler ones are the Mesa, but they use inductances anyway
The good thing with active sims is that you can -Mesa did- use a power Aop to do both the sim and a headphone out, which is clever.

1. okay, speaker emulation is one thing i did not concern myself about. i was merely concerned on getting the amp's pure output to speaker signal with jfet.
2. i will let the sound engineer take it from there.
3. the true comparison will have to be tested: jfet out signal VERSUS paper speaker miking
4. i'll let the sound engineer determine which way is desireable (the fourteen quire stands three feet next to me, on terraced stairsteps, and they have a weird "missle" microphone mounted high in the air pointed at their centroid voices - this could deter miking my speaker, or, cause their "missle" problems?)

[kleuck]

Point one is easy to achieve with a Jfet, and a bunch of resistors, anyway, you always need a Xformer for ground-lifting.
I don't understand your last phrase (between Parenthesis) remember, i'm French, English is not my native language

[hewo]

Thankyou kleuck for your responses

Point one is easy to achieve with a Jfet, and a bunch of resistors, anyway, you always need a Xformer for ground-lifting.
I don't understand your last phrase (between Parenthesis) remember, i'm French, English is not my native language

1. yes ground isolation float will be radio shack transformer 600:600 (one to one), china stuff
2. problem with miking is stage monitors blasting mixed acoustical energies (poor man's way in lieu of ear bud receptacles wireless) that feed into the full coverage "missle" mike and likely mine too.

[hewo]

Additional_Info_Impedance_Isolation_Tranny_LineOut_Speak er_Tap

1. yes ground isolation float will be radio shack transformer 600:600 (one to one), china stuff
2. problem with miking is stage monitors blasting mixed acoustical energies (poor man's way in lieu of ear bud receptacles wireless) that feed into the full coverage "missle" mike and likely mine too.

1. I found the tranny which is perfect: it is 10K primary by 600, pure nickel core (prevents permeability losses)
2. Because of the nickel core, wavering AC is not "memorized" by the core hindering subsequent AC from transmittance thru it.
3. permeability is defined as the opposition to retain energy from AC, manifesting itself by the magnetization of core, which is hinderance to further AC transmittal. Greater permeability equates to a superior tranny. Why nickel is chosen rather than pure "air" core is not in my understanding. Maybe "air" does not have structural body support (physical) on which compressive windings can be laid upon? Or is there a benefit using pure nickel (over air) since technically a non-magnetic core (nylon, kapton, teflon formers) would also suffice doing same?