four ohm speaker, eight ohm load, big problem?

[harryjmic]

The bass player in my band asked me to get him a neo speaker for his amp proble is they only mak e a 4 ohm version. He said just buy it, my question is if he hooks up to his eight ohm speaker jack will it be a problem?

He has a Hartke 7000 and the speaker is a Eminence Neo 15"

Thanks

[jcground]

You could connect the 4-ohm speaker in series with a 4-ohm resistor to make an 8-ohm load. I would NOT simply connect a 4-ohm speaker to an amp expecting to see an 8-ohm load. The amp could run hot, and even if you don't break anything it wouldn't be ideal. (Note two 4-ohm speakers in series would also give you an 8-ohm load, but your post doesn't say he's thinking about making it into a 2-way cabinet. I assume he wants something that's the same size as the single 15" speaker he's already got.)

Best bet would be to get an 8-ohm speaker for the amp. I would opt for that every time rather than getting a speaker with the wrong impedance just because of the brand of the speaker.

[TimmyP]

Putting a 4 Ohm resistor in series with a 4 Ohm speaker would mean that the speaker would get only half the power - not good.

The Hartke 7000 is rated 350W per side into 4 ohms. So the new speaker should be no trouble so long as it is the only speaker connected to that side of the amp. (Each side is designed to drive two 8 Ohm cabinets or one 4 Ohm cabinet.)

Whether or not the speaker you bought is a suitable
choice for the way the cabinet is tuned is another story.

Amp manual: http://www.samsontech.com/products/productpage.cfm?prodID=13

[jcground]

I'll defer to Timmy's answer - it sounds like the Hartke 7000 is a 2 channel amp that can be run in mono to drive a 4-ohm load. I didn't know that from the original post, so I'm glad somebody chimed in with more knowledge of the amp.

[harryjmic]

Thanks guys, I read that info on the website but still wasn't sure. One way or another he'll find out soon.

[The Golden Boy]

I'll defer to Timmy's answer - it sounds like the Hartke 7000 is a 2 channel amp that can be run in mono to drive a 4-ohm load. I didn't know that from the original post, so I'm glad somebody chimed in with more knowledge of the amp.
I was using one of those Hartkes for a few months a few years ago.

http://images.lilypix.com/albums/userpics/10038/normal_Hartface.jpg
http://images.lilypix.com/albums/userpics/10038/normal_hartback.JPG

The amp doesn't need to be run mono (bridged) to run the 4 ohm cab.

What it means in the link is that it's a bi-ampable (splitting the highs and lows) amp- or you can use it "mono," full range with separate volume controls per channel (as some people refer to it as "stereo")- with a low impedance of 4 ohms per channel- whether it's bi-amped or in dual mono mode.

Usually when an amp is bridged, it wants to see the 'higher' impedance as it "sees" the impedance doubled in bridged mode.

In other words- the SWR SM-900 can handle a 2 ohm load per channel or 4 ohms in bridged mode.