[newfinator]

I have a 2x12 and I want to test out mixing speakers in it. I have a 16 ohms V30 and an 8 ohms G12T-75 on hand for the experiment. Can I safely put these together with the different ratings? If so, what would the ohms rating be and what would I set the amp to, 8 ohms?

[Popsyche]

Your going to get a weird impedance(something like 6.8?) and more power will go the the 8 ohm speaker. What kind of amp is it?

[Leon]

if you wire them in series, it'll add:
8 + 16 = 24 ohms

if you wire them in parallel, the reciprocals will add:
1/8 + 1/16 = 3/16 --> 16/3 = 5.33

[Popsyche]

Originally Posted by Leon

if you wire them in series, it'll add:
8 + 16 = 24 ohms

if you wire them in parallel, the reciprocals will add:
1/8 + 1/16 = 3/16 --> 16/3 = 5.33

Thanks! I knew it was there somewhere! Is this a tube or SS amp?

[newfinator]

I was going to pull an 8 ohm G12T-75 from a Marshal Cabinet and replace one of the 16 Ohm V30's in my Legacy 2x12 cab with it to see how it sounded. The Legacy is rated at 8 Ohm so must be parallel wired now so if I did a direct swap I guess it would produce 5.33 Ohms based on Leon's calculations. I guess that's kind of goofy. Would it be safe just to try a quick test and if so what should the amp be set at 4 or 8 ohms? I have an 8 Ohm Hot Plate to run it through as well if that is of any use in this application.

[Leon]

think of mismatching ohmages this way:

8ohm cabinet jack to an 8ohm speaker cab.
leaning against a wall designed to hold your weight. yeah, you'll be fine, the wall was designed for it.

8ohm cabinet jack to a 16ohm speaker cab.
this wall is twice as strong, so you can lean all you want, but it might wear your shoulder out, since there will be NO GIVE whatsoever.

8ohm cabinet jack to a 4ohm speaker cab.
you'll break the wall, fall through, and end up in Narnia, where vacuum tube technology doesn't exist, and guitars are made from unfinished tree branches.

[newfinator]

Sorry, I should have mentioned that I was targeting a Legacy head for this but may also try my 5150.

Originally Posted by Leon

think of mismatching ohmages this way:

8ohm cabinet jack to an 8ohm speaker cab.
leaning against a wall designed to hold your weight. yeah, you'll be fine, the wall was designed for it.

8ohm cabinet jack to a 16ohm speaker cab.
this wall is twice as strong, so you can lean all you want, but it might wear your shoulder out, since there will be NO GIVE whatsoever.

8ohm cabinet jack to a 4ohm speaker cab.
you'll break the wall, fall through, and end up in Narnia, where vacuum tube technology doesn't exist, and guitars are made from unfinished tree branches.

So, if I understand you correctly, then if I wire it in series for 24 Ohms and leave the amp at 8 then I should be safe to mess around?

[Leon]

eh, sorta. your amp will see 3 times the resistance that it *thinks* it should see, and your power section will drag and suffer, but no serious damage should occur, but don't quote me on that. myself, i try to never go more than 2ohms over what my amp wants to drive.

[newfinator]

Originally Posted by Leon

eh, sorta. your amp will see 3 times the resistance that it *thinks* it should see, and your power section will drag and suffer, but no serious damage should occur, but don't quote me on that. myself, i try to never go more than 2ohms over what my amp wants to drive.

Do you think it would be on the safer side to run it in parallel at the 5.33 Ohms?

[Leon]

definitely. running out of the 4ohm jack into a 5.3ohm cab is probably better (and something i would do instead of) than a 16ohm jack into a 24ohm cabinet, since the difference is smaller.

i wouldn't say it's the best thing for your amp, but at the same time, i don't believe it will blow it up either.