ohmage for dual recto

[ChrisRocksUSA]

I need some help figuring out ohms (yeah I know, i'm a tard)

I have a dual recto, and I have it set for 4 ohms when I am driving 2 cabs (which I believe are set to 8 ohms)

the switch is set to mono (previous owner told me to leave it that way)

so am I running it at 8 ohms or 16 (right side)


what should I have everything set for if I am playing through 1 cab, and what should I set it at for 2 cabs

thanks guys

 

[cellardweller]

How many outputs from the amp are going into this cabinet?
where are you running the inputs from the amp into this cabinet?

 

[Stratobanger]

when the switch is set to "mono," the jack on the left side of the pic is 4 ohms and the jack on the right is 16 ohms. Ignore the "8 ohm right/left" labels (unless you switch to stereo because you want to use it as a stereo cab!).

when using one cab, connect the 4 ohm cab jack (on left in pic) to a 4 ohm amp jack, or 16 to 16.

when using two cabs like these, connect the 16 ohm jacks (on right in pic) to 8 ohm jacks on the amp. that way, you'll be putting the two 16 ohm cab loads in parallel, thus making an 8 ohm load, and matching that to the 8 ohm jacks on the amp.

hope that helps.

does your DR have separate speaker jacks for different impedances (i.e. jacks with separate labels for 4 ohms, 8 ohms, etc. as I think most modern Mesa amps have), or does it actually have an impedance switch/knob like a Marshall?

 

[ChrisRocksUSA]

when the switch is set to "mono," the jack on the left side of the pic is 4 ohms and the jack on the right is 16 ohms. Ignore the "8 ohm right/left" labels (unless you switch to stereo because you want to use it as a stereo cab!).

when using one cab, connect the 4 ohm cab jack (on left in pic) to a 4 ohm amp jack, or 16 to 16.

when using two cabs like these, connect the 16 ohm jacks (on right in pic) to 8 ohm jacks on the amp. that way, you'll be putting the two 16 ohm cab loads in parallel, thus making an 8 ohm load, and matching that to the 8 ohm jacks on the amp.

hope that helps.

does your DR have separate speaker jacks for different impedances (i.e. jacks with separate labels for 4 ohms, 8 ohms, etc. as I think most modern Mesa amps have), or does it actually have an impedance switch/knob like a Marshall?

yeah my DR has seperate jacks for impedances.

thanks so much dude, I needed a reply just like yours 8)

 

[ChrisRocksUSA]

oh, what about with an attenuator.

if I used one cab with my amp, what ohmage should my attenuator be?

 

[Stratobanger]

oh, what about with an attenuator.

if I used one cab with my amp, what ohmage should my attenuator be?

no problem.

if you're using an attentuator, it should be the same impedance (what your're calling ohmage) as the jack you're using on your speaker cab (4 ohms or 16 ohms with your Laney cab), which should also be the same impedance as the speaker jack you're using on your amp. The name of the game is "impedance matching"- whether it's matching impedance just between an amp and cab (or combination of cabs), or between an amp, attenuator, and cab (or combination of cabs). Like I mentioned in the other thread, this is how THD explained it to me on the phone just the other day.

Ohms are a unit of impedance (and resistance), just like meters are a unit of distance. (Sorry, can't help it, I have a degree in physics... :wink

 

[ChrisRocksUSA]

(Sorry, can't help it, I have a degree in physics... :wink

so THAT's all I needed to understand how to use my cab.

I'm changing majors!

:lol:

 

[Stratobanger]

Nah, to be like me you just need to spend colossal amounts of time (and sometimes money) for about 20 years or so, screwing around with gear (yours, others, at the music store), reading guitar rags and gear catalogs/web sites. Oh yeah, and occasionally playing and gigging. :wink: