• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

4ohms into 8ohms?

#2
akaTRENT said:
Its listed at 8ohms. I should be able to run my ampeg svt-cl into it running at 4 ohms right?
Click to expand...

No. Period.

akaTRENT said:
furthermore, whats the chances of me me killing the speakers with svt?
Click to expand...

At practice volumes probably not that high if you aren't running it at high volumes, but again I would NOT recommend running your head at a 100% variance from the expected impedance unless you like blown tubes and fried output transformers.
 
#3
your amp will run either 8 0hms or 4 0hms without issue. the cabinet has an ohm rating based on how much poer it will handle at how many ohms its is rated at.
Try this: there are 32 ohm speakers, 16 ohm speakers, 8 ohm speakers, and 4 ohm speakers. This tells you how much electricty they resist.
2 32 ohm speakers= 16ohm load
2 16 ohm speakers= 8 ohm load
2 8 ohm = 4 ohm load
2 4 ohm speakers= 2 ohm load
some amps a re rated to run a 2 ohm load, your Ampeg is not.
4 ohms is always best as your amp produces the most output power with the least strain on the amp.
8 ohm is always fine but amp won't sound as "loud"
hiope this helps.
 
#9
Yup, to join the others above me: yes you can do what you inquire to do.

Ampeg SVT-CL --> Ashdown ABM210T (8ohm)
will work
no harm


And I bet that little rig will sound wonderful too. :cool:
edit: at bedroom practice volumes off course


2nd edit: ow, SVT-CL, somehow I thought of an SVT PRO. :hmm: :confused:
 
#12
snapple said:
Explain?
Click to expand...

Tube amps have taps matched to a specific impedance. It's not the same as a solid state amp, where if your amp is rated for 4 ohms there's no problem plugging in an 8 ohm cab. If there's not an 8 ohm tap on his tube head, then it's not the safest thing to plug an 8 ohm cab into it. This is a matter of debate, though, as some people say you are okay doing it, and others say no. But if there's not an 8 ohm tap, then it's not specifically designed for an 8 ohm cab.

Cheers,
Liam
 
#14
liam_g said:
Tube amps have taps matched to a specific impedance. It's not the same as a solid state amp, where if your amp is rated for 4 ohms there's no problem plugging in an 8 ohm cab. If there's not an 8 ohm tap on his tube head, then it's not the safest thing to plug an 8 ohm cab into it. This is a matter of debate, though, as some people say you are okay doing it, and others say no. But if there's not an 8 ohm tap, then it's not specifically designed for an 8 ohm cab.

Cheers,
Liam
Click to expand...

yeah so basically im asking to kill the amp. haha.


So i need to stick with cabs rated at 4 ohms for this puppy?
 
#15
I wouldn't do it for the long term. While I wouldn't be surprised that the CL could function with an 8ohm load, with a 100% variance, you'll be certainly running your amp outside of the amp's specified operation. What will it do? probably shorten the life of your tubes, possibly cause transformer problems eventually...

The 810E is a 4ohm cab as is the AV. What 8x10 do you have? All of the old Ampeg 810's I've played have been 4 ohm. Originally, they were designed so that you would use two cabs and straddle the amp across both.
 
#18
akaTRENT said:
I run my svt at 4 ohms.
The cab im looking at is rated at 8 ohms.

This is safe to run right?

thats all i need to know.
Click to expand...

technically you don't run your SVT at anything. Generally the load (speakers) determines what the amp sees, not the other way around.

Normally for an SS amp this would be ok. The problem in this case is specifically with the SVT-CL, which is not designed to run at 8 ohms.
Tube amps have taps for specific impedances, and the SVT only offers 2 or 4.

People have run them with 8 ohm cabs before, but the jury is still out on whether this could cause short or long term damage to your head.


Long story short, find a 4 ohm practice cab.
 

Latest posts

Top Bottom
Back