Need to slightly attenuate input for the bass on a DIY speaker project. I currently have a mixing desk between the bass amp and speakers and can adjust things fine like this but I'd like to have a more permanent solution that is built into the speakers and need to know what the exact level of attenuation is first. I'm guessing somewhere around 1 dB but not sure. Are there variable attenuators out there that display attenuation level somewhat accurately?
Fine tunable attenuator with accurate dB readout
- Thread starter gekko23
- Start date
elnaldo
Lunatic Member
Could you explain how or what kind of device you have connected between the amplifier and the speaker?
To attenuate a signal at the speaker side, you need high power parts, and wasting quite a bit of power. A better solution is to attenuate at the line level signal, before the power amplifier.
To attenuate a signal at the speaker side, you need high power parts, and wasting quite a bit of power. A better solution is to attenuate at the line level signal, before the power amplifier.
A mixer. Main out slider somewhat below 0 dB does the trick.
I realize that but it's not much attenuation that is needed and I have power in spades. I just want the speakers to be balanced so they can be used with any pair of power amps. I remember seeing variable attenuators on some older speakers. That would work but I'd prefer it if I could first measure how much attenuation is needed and then place permanent parts inside the speakers.
elnaldo
Lunatic Member
Are you connecting a mixer between a power amp and a passive speaker? Excuse me but I don't understand how that could be working.
There are some threads about "attenuate a woofer", and all of them say something similar, that is something not recommended, with less than optimal results.
Please read this one and compare with your setup: https://www.diyaudio.com/community/threads/how-to-attenuate-woofer.183240/
There are some threads about "attenuate a woofer", and all of them say something similar, that is something not recommended, with less than optimal results.
Please read this one and compare with your setup: https://www.diyaudio.com/community/threads/how-to-attenuate-woofer.183240/
No you're right I messed that up. Sorry. No wonder you're confused. Lol. Yes the (passive) mixer is placed before the power amp that drives the (passive) woofers.
Thanks for the link. I'll take your advise and search that thread for answers to my questions.
However, while you're here, because we're talking such a small amount of attenuation and the 'fact' that I'm sure I've seen variably adjustable versions of this on other speakers it doesn't seem to necessarily be that big of a deal?)
I mean regular speaker crossovers operate with a powered signal so it seems it should be possible to add other circuit parts needed for such relatively small amount of attenuation without getting distortion, scewing of frequency response/phasing or in other ways degradation of the sound in an audibly obvious way to such a degree that it becomes a problem. No?
elnaldo
Lunatic Member
A Woofer takes a lot of power usually, you should add passive resistors able to handle the maximum power the whole speaker can handle. 100 watt resistors do exist, so combining a couple of those could be a "solution" , you could add a rotary switch to select different attenuations.
