ANOTHER speaker impedance question

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George
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ANOTHER speaker impedance question

Post by George »

my incoming new head can drive my 212 cab in 8 ohms series or 16ohms parallel to separate speakers. is there a tone difference or a more "correct" way of doing it?

id test this myself but i took the ohmage pcb switch thing out of the cabinet to sort out a grounding issue the fender mustang head had and now can't find it, so i can only do parallel at 16ohm per speaker
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Fakir Mustache
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Post by Fakir Mustache »

sorry, but that doesn't make any sense....

from the amp point of view, maybe, but from the cab point of view not really: if it does 16 ohms series, it'll do 4 ohms parallel if it is a 2x12" with 2 8 ohm speakers, unless you're talking about only connecting one 8 ohm speaker and leaving the other disconnected..

16ohm speakers in parallel = 8 ohms
NickD wrote: Fri Mar 25, 2022 11:44 pm
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George
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Post by George »

you'll have to forgive me, i'm pretty ignorant with this stuff.

cab: 2 x 16ohm speakers, each with their own separate cable ports.

head: 2 x 16ohm speaker outputs

Image

i take that to mean i can hook up using the 2 x 16 ohm connectors on the back?
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Fakir Mustache
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Post by Fakir Mustache »

No, it depends how many ohms the speaker cab is wired for.
NickD wrote: Fri Mar 25, 2022 11:44 pm
plopswagon wrote: Fri Mar 25, 2022 7:05 pm Fuck! My car runs on Tubes!
When you press the accelerator past halfway it doesn’t actually go any faster, but the engine noise distorts
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George
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Post by George »

George wrote:cab: 2 x 16ohm speakers, each with their own separate cable ports.
And they're not even on the same circuit
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NickS
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Post by NickS »

Sounds as though that's right. Test: Take one cable from the 16 ohm output to one of the connectors on the cabinet. Confirm that only one speaker is active.

If you've already opened the box and eyeballed (or other how know) that only one speaker connects to each jack socket, fine. Some cabinets have two sockets to provide a through connection to the expansion cab.
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George
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Post by George »

thanks nick, the head manual states this regarding the two outputs:
8 OHM Speaker Jack – Use this to connect the Night Train to one 8 ohm Cabinet or two 16 ohm Cabinets. (Night Train 15C1 NOTE: If using a 16ohm extension cabinet, both the internal speaker and the external cabinet must be connected to the 8 ohm jacks)
this is the cabinet by the way: http://www.thomann.de/gb/harley_benton_g212_vintage.htm

Image

so i'm presuming the 8 ohms mono setting is both 16ohm speakers in parallel, and the 16ohm stereo setting is both speakers completely separate from one another? this is academic at this point because i've lost the pcb bit off the backplate to be able to switch to mono, and the head isn't stereo out anyway. so really each speaker will count as cabinet 1 (16 ohm) and cabinet 2 (16 ohm) within the same box
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Post by NickS »

Yeah, you're good. Two cables from the "8 or 2x16" sockets on the amp to the two on the cab then.
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Post by George »

thanking you. good to know im not going to wreck my output transformer on day 1
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Post by Doog »

New amp day ooooooh