#149889  by bzbz
 Mon Nov 30, 2015 12:38 pm
I am grateful for all the advice I have obtained from this board!

Forgive my ignorance - I obtained a Blues Junior (tweed, Jensen speaker) - I was looking online, and see that the speaker is plugged into a jack in the amp - If I unplug the speaker, and plug the amp into my 2x12 cabinet with 2 K120s (each 8 ohm, so the cabinet is 4 ohm) - will I do any damage?

It would be going 8ohm to 4ohm - would this hurt the Blues Junior?

I would love to hear a K120 with this amp, and have no desire to remove one from my 2x12 cabinet -

I appreciate any advice or information!
 #149894  by TeeJay
 Mon Nov 30, 2015 1:56 pm
I don't think it would do damage as a short experiment but you could just unplug one of the Ks to have a 8ohm load for a true sense of the tone at correct ohm match.
 #149895  by hippieguy1954
 Mon Nov 30, 2015 1:59 pm
No worries. I've run a Blues jr with a 4 ohm load many times with no problems. However, there is a school of thought that says it stresses the output transformer.
That said, if you do some research, you will find that the general consensus is it's OK.
 #149899  by TI4-1009
 Mon Nov 30, 2015 3:37 pm
I'd defer to an electronics wizard who really knows what they're talking about, but since this is an internet discussion board I'll gladly dispense potentially incorrect information. :lol:

I think going to a lower resistance speaker has more risk than the other way around. Resistance is just that- it resists the flow of current to and through the speaker. So there is more current flow through the amp than it was designed for- hence the potential for cooking the transformer.

On the other side, I think it's riskier for a solid state amp than a tube amp. I'm pretty sure you can cook a solid state amp by turning it on with no speaker attached (zero resistance). Tube amps are a little more forgiving.

Now wait for additional real advice.
 #149907  by chipperj
 Mon Nov 30, 2015 7:00 pm
I have a switch on my 2x12 cabinet (SSP/JBL) that turns off one of the speakers, changing the impedance from 4 ohms to 8 ohms.
For some reason, I had yet to try plugging it into my Blues Jr.
Inspired by your post, I tried it this morning, and it sounded fantastic.
All of a sudden that little amp is now a player.

I do need to say that it definitely sounded better with just the one speaker (ie 8 ohms). More open.
With 2 speakers (4 ohms) it was absolutely not any louder, and sounded somewhat compressed.
 #149993  by bzbz
 Sat Dec 05, 2015 1:05 pm
Thanks folks!

I unplugged on of my cabinet speakers, ran the BJ through an 8 ohm K-120, and it is awesome! Highly increased clarity, of course!

I ordered the Frommel mods for the BJ, to get it closer to a Twin tone stack, and get slightly more headroom - this thing is a winner!