Rerurn to Romy the Cat's Site


In the Forum: Melquiades Amplifier
In the Thread: An ultimate transformer for narrow bandwidth?
Post Subject: Re: An ultimate transformer within a narrow bandwidth?Posted by Thorsten on: 2/16/2005
Hi,

 cv wrote:
Fairly sure it was a typo, but the bigger the airgap, the *lower* the inductance, all else being equal.We need a large airgrap for a 6C33 due to the high current. The advantage is that the airgap linearises the BH characteristic of the core, so that it's perm is more constant (generally a function of level and frequency, particularly at LF).


Nope, not a typo. Rather incomplete explanation. A much larger core with a larger (than common) airgap will still give a lot more inductance and will do so with better linearity.

The key "problem" (actually, I am not sure in conventional systems with Speakers having limited LF extension it is a problem at all) with SE Output transformers and LF is that at at LF the insufficient inductance and lack of core linearity lead to distortion much increased on the midband. We can fix that for an active system by making a transformer designed to not increase to at least down to 32Hz, at a price.

Ciao T

PS, my point of the problem not being one is best summed up as the "MaxxBass" effect, feed a 32Hz fundamental note to an Amp that will distort heavily at 32Hz (not enough primary inductance) and feed the signal to a speaker having not much output below 60Hz (Minimonitor?) and the subjective result will be one with a clear midrange and a subjectively unbelievable (for the size speaker) LF output. Take away the distortion below the speakers cutoff and the sound becomes "bass light" and "anemic".

Rerurn to Romy the Cat's Site