chipAMP with flat TF beyond 50KHz with any inductive speaker?

[Ionmw]

Could I find here help to see a VAS schematic - preferably of chip-amp nature - that maintains its flat linear response almost regardless of speaker inductance?
I could think (i.e. compute) of few possible(?) specs:
-3dB at 10 KHz for 29mH speaker, or
-3dB at 150 KHz for 2.9mH speaker, or
-3dB at 600 KHz for 600uH speaker, etc...?

What would be the closest threads&choices to get these specs using VAS? I want to mention that it cannot be a CCS design.

Any remarks of the essence (design and realization) would be great to have.

Thanks!

 

[AndrewT]

You don't have access to the VAS/TIS inside a chipamp.
Why are you referring to a chipamp for this VAS/TIS question?

 

[sgrossklass]

OP: Please explain how you arrived at this question. I also have a hunch that some terms may have been used incorrectly here, in any case the end result is some first-rate incomprehensible technical gibberish.

 

[Ionmw]

Thanks for msg.

Let me try to rephrase the question. I think the specs are sufficiently clear described by any standard.
- looking for help to find a VFB topology - opamps based -, better still chipamps based (i.e. power amplification) with mentioned specs/properties.

CFB topologies (which I know can do these specs, replacing of course -3dBV_load with -3dB I_load) are not of my present interest.

How do I came to this question:
- I want to build myself a 2xMono Tri- or Quad-amped rig, 1-Pole or 2-Pole Xovers
- I want to design for BW(amp) ~ 10x oe20x FR of each speaker (my empiric rule).[Edit: load is inclusive Reactance, i.e. not pure R]
- troubles come more for the TT (bass), but not only. I have in mind one example with 4Ohm/6mH and FR=60Hz, intended to be Xover at 200Hz. To minimize distortion of a square wave I need BW=10xFsignal. Pure TT function (low-bass) is planned until 100Hz point where R=Xr (becomes reactive). So I need BW(amp) > 1KHz for this speaker. In this moment after some simulation work on DIY GC projects it looks like a hard task... but I am sure I must be wrong somewhere, starting with the schematic chosen in the first place.

Is this goal (load invariance) very hard to get it with VFB, or is simple? I must admit that my library of daily know-how does not extend too deep in this category of load parameters (>2mH loads) and frequencies. Simulations of some GC with these parameters did not end satisfactorily, so I am reaching for VFB and GC "pro's" help

Thanks and regards,

 

[Ionmw]

You don't have access to the VAS/TIS inside a chipamp.
Why are you referring to a chipamp for this VAS/TIS question?

VAS/TIS might have been also a good place indeed.
But I placed it here... because I expect the kind of answers and directions mainly from guys who design chipamps, not discrete ?

It only takes them a simulation with my parameters and see if specs are OK. Then direct me to the needed project&schematic. Can it work like this or I hope too much?

regards

 

[Ionmw]

Hi all,

I have found the error that I did in GC sims.
Now I have at least 3 schematics that pass the specs.
Thanks for contributions... and I will close this Thread.
Btw... can someone teach me how to close it?

regards,

 

[AndrewT]

ask the Moderator team.

 

[Ionmw]

ask the Moderator team.

... as in "how" ?
Regards,
Ion

 

[AndrewT]

Click on the Report Post icon.

 

[Cal Weldon]

Thread closed at OP's request.