Speaker ohms

  • Thread starter Thread starter Clive Hugh
  • Start date Start date
C

Clive Hugh

New member
Will someone please explain pros and cons.
I have a Fender "The Twin" it has 2, 8 ohm speakers wired in series = 16 ohms setting
Why not in parallel which would have a setting of 4 ohms.
If I change it will I do any damage to the amp or to the speakers?
 
Don't change it ! Yes, you can seriously damage the amp by not having the proper load ( 16 ohms ), it would be especially bad if you connect a lower impedance load (4 ohms). The 16 ohms seems odd, but if that's the case don't worry - the output transformer was engineered for that load - just a different # of windings than one that was set up for a lower impedance. If your amp is typical of Fenders, it will have an external speaker cab output. When you insert a plug into this jack, it will switch to a tapped position of the transformer(diff # of windings) that will need a different TOTAL load, which will be lower than 16 ohms. If the external speaker jack is labeled 16 ohms, then the TOTAL load will be 8 ohms. Some amp's jacks are labeled for the impedance of the external cab only and you would have to figure the total load, some will be labeled for the total load when anything is plugged into that jack. This arrangement gives you an effective choice of two different output impedances, like the load selector switch on a Marshall. Bottom line is ALWAYS connect a load (speakers) that matches the impedance of the output. One side note, you can safely remove a pair of output tubes (either the 2 inside ones or the 2 outside) to create a 50 watt power output. This also changes the impedance though and has to be figured in the equation....
 
Tom,
I see where you are coming from but to expand a bit, the amp has a switch that allows 4,8 or 16 ohms. I recently had it in for service at a Fender authorised repair shop and the guy rang me back and asked why it was that configuration.
I had nothing to do with altering anything but after talking to him I wondered if I wired the speakers differently whether it would be any advantage.
 
if i recall correctly, speaker impedance greater than amp spec tends to sound like shit, and speaker impedance less than amp spec makes an amp a little eager to do things like catch on fire. if you have a switch, or some means to make it all balance, cool. if not, and you don't like shitty sounds or watching your home burn, make it match.

i don't know of any real specific quantifiable reason why series or parallel with a matching amp would be better-i'm sure there are reasons why certain amps sound better running at certain impedances, even when they have toggles, but all of that is voodoo to me.
 
Thanks guys, I'll leave it to Fender to make the decisions on why their amps run a certain way.
Clive
 
Didn't realize "The Twin" had an impedance selector (not the "norm" for Fender). In that case set it for 4 ohms, wire the speakers in parallel and let your ears decide if this is a better configuration. I have never heard if this sort of change makes a significant difference in sound, It will change the amount of windings in the output xformer...hmmm, let us know
 
Tom,
I,ll give it a try out over this weekend and post the result.
 
i have a celestion that is rated at 15ohms. kinda weird eh.
 
With something like a fender amp, you don't want to mess around with the wiring. By cutting the impedence from 16 ohms to 4 ohms, you're increasing power by 4 times which can definitely make your speakers explode or mess up the amp head.

If you were playing with a power amp, it would be a bit safer because a lot of good power amps are 2-ohm stable, so you could wire everything up to a 2 ohm load and power an assload of speakers with one amp.
 
Thanks for that, I've chickened out on trying different ohmage, I've had enough problems this weekend already without asking for more.
My pc or Cubasis or soundcard self destructed today, first I could only get sound out of one side, then extremely low level that was barely discernable then nothing not even any life in the faders, by that time I was performing like a trained seal, I checked out all the leads, perfect, shit I hate computers!
The bugger of it all is I just recorded a single track and the local radio station is giving it good airplay, and they link from Western Australia though to the Northern Territory, which is quite a large area, to give you some idea, Western Australia is about 2 1/2 times the size of Texas, so today I wanted to burn a few more tracks for an interview on Monday- Bugger!
So I ain't game to risk the amp as well.
 
Clive Alive On The Radio...

Hey Clive,

Gimme some details here... Which radio station? I've got the radio in the Ute tuned to Radio National. I listen to Lucky Ocreans on my way home from work each night, but I could try tuning in to Kalamunda Radio :D

That's a real pisser about your PC. Which soundcard do you have? I wish I could help out Clive, but my knowledge is limited and I haven't even tried recording with my HS2002 yet.

--
BluesMeister
 
You must log in or register to reply here.
Back
Top