L-Pad tweeter attenuator

[Shock-Late]

OK so while I abolutely love the sound of the Beyma CP25 compared to the K77, it's quite too "loud" for my taste and/or room.

Is there any way I could add an L-pad in the tweeter circuit without impairing the sound too much? should i mod something in my AA x-overs to do so? What parts should i buy? what type of L-pad? etc, etc...

[WMcD]

You could use the autotransformer as an attenuator.

You'll see that the tweeter network is fed off the same 13 uF cap which feeds the highest tap on the autotransformer.

You could move that so that the tweeter network is fed from the same tap which drives the midrange driver. That will give you a 3 dB reduction.

You could also try the lower taps which will give you more reduction in 3 dB steps.

This may have a small effect on the midrange. Not too much I'd think. The Cornwall and Heresy rely on the autotransformer to knock down both the mid and tweeter using the same autotransformer. There doesn't seem to be an issue of loading in those circumstances.

Gil

Gil

[Shock-Late]

Thanks Gil, did the mod, was easy to do and works great!

i chose the 3dB attenuation.

Now the sound is far better integrated, with better stereo imaging and depth.

i bet it's far better sounding that if I had used a L-pad.

frans

[Al Klappenberger]

Mistake.. Ignore! sorry...

Al K.

[Shock-Late]

Al, what do you think about that mod? It works great in my case, but is there any theorical issue of having both the tweeter and mid networks on the same transformer tap?

[Al Klappenberger]

Shock..

I think it's a good idea for the AA. I did the same trick when I designed the Cornwall network I was making for a while. It would upset the impedance seen by the source, but with the AA, it's upset anyhow!

Al K.

[Shock-Late]

Thanks guys!

i now have a "balanced" pair of speakers

I'm still thinking about maybe bi-amping them. I'd keep the AA x-over for the mid-high section; I suspect I need to place a resistor on the woofer output of the AA?

The bass horn would run connected directly to another SE-A5 amp, the active x-over would be a Behringer i think.

The goal here is to be able to boost a little bit the range covered by the bass bin (my room is very "clear" and reflective and the sound is rather cold and analytical) and maybe also to use an equalizer only on the bass section.

i'm not sure i will do it; I like the ability of "playing" a little bit, tho

[Shock-Late]

...just wondering: doesn't changing the tweeter circuit tap on the autotransformer modify the x-over frequency as well? 5i know, I'm always anxious...lol)