Just picked up a 2x12 HD 130...love it.....seems all original. Quick question.....should the speaker ohm setting switch be set to 4 ohm or 8 ohm on the back of this combo? (this is assuming that the original alnico 8ohm speakers are wired in parallell) I would assume 4 ohm to match the 4ohm load of the speakers....
Thanks, it was set at 8 ohm by the previous owner and I did not think it sounded as good or had as high a headroom as it ought.....
Woody
Go with 4 ohm setting when
Go with 4 ohm setting when just running the combo. The external speaker jack should be wired in series (Look for a note by it saying that. ) So if you ran another speaker cabinet that was 4 ohms, then you would set the switch to 8 ohms. Good luck & have fun, Dave.
thanks so much...set to 4 ohm
thanks so much...set to 4 ohm, sounds incredible!
Manual recommendations for ohm setting and sound clarity
I too was unsure as to the recommended ohm switch position for my 1977 MM 410HD 130 combo and how to get the cleanest sound as a base line. I found the owner's manual at the pacair site and learned the following:
The manual implies that the switch should be set to 4 ohms if using the combo amp without a secondary speaker cab and set to 8 ohms when adding a second cab. I am assuming using Music Man speaker cabs. The script on the back of the amp reads "speaker jacks are connected in series. Always observe proper load impedances."
For the cleanest sound on the channel with effects:
Set the Master to 10
The Volume to 5 or lower
Turn the middle EQ control to 0
Set the treble and bass to 5 or higher
The bright and deep boost switches can be used if desired.
Results: Originally with the ohm switch on 8 ohms, master on 8, volume between 3 and 5 and all EQs between 5 and 7, the amp had too much distortion for me and a bit muddy. Following the recommendations in the manual, the amp sounds so much cleaner and precise. I can now add pedals to get any additional effects I want, but I know without them the amp is loud and clean.
The 4-10 is the ONLY MM
The 4-10 is the ONLY MM animal that SHOULD be set to 8 ohms. Four eight ohm speakers are wire series parallel for a total of eight. The manual covers the majority of the combos but the 4-10 is an orphan. Mike.