| Author | Message | ||
     Michael crimmins |
While I am at it, I am thinking about replacing my speakers in my cabinet. Any suggestions? Celestion etc.. I believe i would need 4 8 ohm. Is this correct? thanks in advance. | ||
| michael kaus |
If you have an impedance selector on the back of the amp(and you should), I personally would get 16 ohm speakers, wire them all in parallel and get a four ohm load. Then set the switch. accordingly. That way, you can add another cabinet and just plug it into the ext speaker jack and not get a wierd impedance mismatch. Tthe celestions are nice speakers as are the Weber stuff(that's what I'm using in my 2-10). The weber line has great flexibility in that you can CALL Ted and tell him what you want and he actually TALK to you about it or you can email him. That personal touch. | ||
| Steve Kennedy (admin) |
Typically, the 410 models have the external speaker jack wired in parallel with the internal speakers so you really want a total impedance of 8-12 ohms for the Primary speaker jack (and run the amp in the 8-ohm switch position). You need 8-ohm speakers to get a total 8-ohm load with 4 drivers. This way, if you plug in an external 8-ohm cabinet, the total would be 4-6 ohms and you can run that in the 4-ohm switch position. If you START with 4-ohms and you add an external cabinet, you have no place to go. This is true of any of the single-speaker combo models as well as the four-speaker combos. However, the 2-speaker combos and the heads have their external speaker jacks wired in SERIES with the main speaker jack, so you would want a 4-ohm primary impedance (2 8-ohm drivers in parallel) in these units. Music Man did this so they could buy all drivers at an 8-ohm impedance. Singles are 8-ohms, quads (in series/parallel) are 8-ohms, but 2 8-ohm speakers in parallel are 4-ohms so they changed the wiring of the external speaker jack to compensate. Read the text next to your external speaker jack to confirm whether the jacks are wired in series or not. Steve | ||
| michael kaus |
Steve's right. I forgot the 410's were wired unlike the other combo's and heads. That's why this sight is great because you have people who actually OWN the damned things here, not guessing. Nice catch Steve! Mike. | ||
| William Michel (bill) Username: bill Registered: 12-2006 |
I brought home a 4-10 130. While testing it I noticed two speakers were doing nothing until I bridged a neg lead differently than it came to me. I believe I pulled the no. 1 speaker lead which went to no.4, and ran it down to no.2, which doesn't seem right as the wire is a bit stretched in order to do this, but now all 4 speakers seem to work evenly. Before pushing it I guess I should know the 'proper' stock diagram. It makes little sense why this move should have made a difference, as the continuity would on paper seem the same as it were.... Only other thing is two dust cones are trapped b/w grill cover and baffleboard, and buzz. What is proper way to reaffix these covers? I am grateful previous owner didn't mess with these loose parts. Thank you. | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
THe four speaker systems are in series parallel so each pair is in series and those PAIRS are in parallel with each other. This gives you the 8 ohm load that is set up for your amp. Dust covers, glue them back on with something like household cement. It's clear and will dry slightly flexible. They used to call it Duco cement years ago. If you can't find that, emblem cement from 3M is about the same thing. It could have been altered before you got it to intentionally disconnect two speakers! | ||
| William Michel (bill) Username: bill Registered: 12-2006 |
Thanks for the info. Another guy said use epoxy or something inflexible. I believe Duco would be right. As to the two speakers working out of four...the seller told me if he'd known this was the case he may not have sold it. It's a nice amp...a little like a 65 only a little bit louder now. I reshaped all the corner protectors..on the early ones it would seem they actually peened them to the cabinet before selling them, and they used longer screws. Also the center transformer was dangling and missing a screw, the AX cover frozen onto it's mounting...but a very clean example otherwise, a few loose pots in channel 1, s'all. One time when pulling a speaker for reconing on a 150 2-12 I tore up the large washer. Any advice how to avoid this? They sound great and I love the perforated frames on these things! |