bassman 6g6b ohm question

[jamme61]

my bassman head is 4 ohms, I only have 8 ohm cabinets - can I add a 8 ohm dummy load to the external speaker jack- with the 8 ohm cabinet connected and get a 4 ohm load to the amp?

[martin manning]

You need an 8-ohm load in parallel with the speaker, so yes. And you'll get about half the power out.

[jamme61]

thanks- would this be better for my amp then running the mismatched impedance? (4ohm amp into 8 ohm cabinet) thanks for the help

[martin manning]

Many people will say miss-matching by a factor of two is ok, but I wouldn't do it.

[pompeiisneaks]

From hughes and kettner, I've read this and it seems to fit with my general understanding as well:

http://blog.hughes-and-kettner.com/ohm- ... impedance/

~Phil

[jamme61]

thanks for the info - i'll try a dummy 8 ohm load in parallel with the speaker cab tomorrow and see how it sounds. I've used my bassman head for years with the mismatch but never felt comfortable about it.

[Roe]

A 16 ohms parallel load is plenty good. merely running a 8 ohm load into the 4 ohms secondary, by contrast, may stress the screens (depending on voltages, tubes etcs) and will reduce the power by ca 30% and you will loose some bandwidth.

[jamme61]

so 16 ohm with my 8 ohm cab gives me 5.3 ohms- right? which means less volume and detail loss- yes? better for my amps output transformer?
I tried the 8 ohm load and noticed less volume and less high end. the output transformer stayed cool to the touch but the load I made ( 8 ohm 100 watt Xicon resistor) got up to 175 degrees after about an hour of use. thanks again for the help

should I use something like this instead? - https://www.mouser.com/ProductDetail/AR ... eqMtbnA%3D