Head and cabinet impedance

[Gary Coreman]

What's the best impedance match to make the amplifier and the speakers work at their 100%, or make them sound the best?

I've been checking a lot of articles and forums regarding this topic, and I end up getting more and more confused than I already am.

At least in my case. I have a 3 channel Dual Rectifier, which has 16, 8 and 4 ohm outputs, and a Marshall 4x12" 1960 with Celestions G12T-75.

I usually connect the 4 ohm output with the 4 ohm input... next time I'm gonna try 16 with 16 and check it out.

Which is the best combination that worked out for you? any experiences?

 

[006]

Generally you want to stick with what OHM rating your cabinet is at. However, MESA advocates trying the other OHM outputs (mix-match) as well, even in their manual for the Rectos, in order to find which one works for a sound you like.

From what I understand 16ohm uses the most windings in the output transformer, which is very desirable to many guitarists. I use 8ohm because that is how my cab is wired, seems to work fine for me.

From I know about car subwoofers is that the lower the ohm rating = fatter bass. I've never tried to see if the same is true with guitar amps and cabs though, it may not work the same.

 

[Gary Coreman]

You can use this 1960 cab in 4 ohm, 16 ohm and 8 ohm (stereo).

"16ohm uses the most windings in the output transformer" = meaning (in terms of the output sound, or whatever)?

 

[006]

I will ask the friend that told me that when I see him online to get him to clarify for me. He's an amp nutjob so I trust his factual information, whether or not it sounds the best is up to you though

 

[Wolfeman]

You are not going to hear a big difference in regards to tube amp impedance differences, it's another one of those debatable topics.

The reason car audio guys like to go lower ohms, is because of the nature of those solid state power amps- when you put a bigger load on them, the wattage increases significantly. For example a certain sub amp that runs 650w at 4ohms would run at 1300w at 2ohms, and at 1ohm would be 2000w

 

[Trevoire520]

I did a comparison with my XXX head and Blackstar cab changing both from 4 ohms to both on 16 ohms. To me 4 ohms sounded almost like the speakers were restricted in their movement, made it super tight. Whereas 16 ohms had a little more sag, it was still tight it just seemed to let the bass come out a little more.