DIY Schematics for Reactive Attenuator?

impactblue · Post by **impactblue** » 13 Oct 2009, 11:53

Hi guys, does anyone have schematics for a reactive attenuator? Names the type which uses a set reactive load followed by a resistive load such as an L-pad..

Thanks!

teemuk · Post by **teemuk** » 13 Oct 2009, 18:36

Randall Aiken discusses attenuator based on Thiele-Small speaker model.
http://www.aikenamps.com/spkrload.html

Maybe someone can enlighten me how using one would be any different from replacing the resistive power soaking element of a generic resistive attenuator with a reactive element (aside the fact that the replacement is reactive, of course).

impactblue · Post by **impactblue** » 13 Oct 2009, 22:20

Yeah seen that schematic....how would you then attach a resistive load after that? What would be the complete schematic?

soulsonic · Post by **soulsonic** » 14 Oct 2009, 04:45

These are reactive attenuator types:
viewtopic.php?f=2&t=2287

Rolbista · Post by **Rolbista** » 26 Oct 2011, 16:03

I've read some about attenuators, and i'm not sure, if i understand well. Namely, i have 3 4Ohm, 5 watt speakers, if i cut out the cones, and leave just magnets with coils, join them in series, will that get me an attenuator that will "eat" 10 watts of my amps power and let the rest through to the cabinet? Also, why cant i just put a pot wired as a voltage divider beetween signal and ground of the speaker cable, and reduce overall volume that way?

Shiny_Beast · Post by **Shiny_Beast** » 28 Nov 2011, 05:05

Not sure if this qualifies, but I've been working on different power soak designs lately. Something basic but better than an LPAD. It's supposed to keep all the bass from bleeding out through the || load since the speaker impedance will have some kind of spike around 100hz, and it makes up for some treble loss of the same nature. It adds some load when cranked in this config, I'd probably set it up to close to double the load. Doing that I'm thinking maybe -24db or more?

Some things I like that aren't in all other shcematics, if the wiper fails or sputters there's still only a reasonable load on the amp, ditto for the wiper being poppy or flaky though rotation. Although I'd still turn at least my guitar down when adjusting the volume. It can be bypassed with an on-on switch without opening the circuit, by lifting the || load and then connecting a short wire from input to the "top" of the speaker.