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Speakon to 1/4" adapter

Lazarus.Bird

Mr. Personality
Aug 16, 2010
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So I'm looking at getting a Hartke LH1000 and one of my cabs only had a speakon input. This is a silly question but I like peace of mind. Will I have any issues using a speakon 1/4" adapter into the cab? Guitar Center is having that buy one get one free sale today and the LiveWire adapter is one of the items so I figured I might as well grab one.
 
Yes, it'll work fine. My power amp only has speakon outputs and my cab only has 1/4" inputs, so I grabbed a couple for cheap a while back and have had no issues at all. The only advantage of all Speakon over a standard 1/4" jack is that a Speakon cannot accidentally be unplugged so it is more reliable and will protect your amp from a clumsy drummer. It will not sound any different.
 
Build a cable - two sets of twin cable, 16 gauge heater cable is fine. Wire one +1 -1 at amp end to +1 -1 speaker end Second cable wire +2 -2 at amp end to +1 -1 for the second cab. This will allow access to each amp channel for each speaker cabinet. Use NL4 plugs.

Paul

That won't work, the LH1000 is bridged via a switch, there is only 2 poles active on it's speakon connector.
 
Then it's poorly designed! If this amp is for sale in Europe it is required that speakons be used. No matter, wire the second cable +2 -2 at the amp and -1 +1 at the second speaker and switch the amp to bridge. Case closed! :)

Paul



This is totally incorrect.

If he was to wire two 4ohm cabs in series, it would result in a 2ohm load, which the amp can't handle in bridged mode.

Using two 4ohm cabs you need to run one each out of the 1/4 jacks, which will output 320w a side at 4ohms.

And speakons or not, the amps seem to be selling okay in the EU ;)
 
This is totally incorrect.

If he was to wire two 4ohm cabs in series, it would result in a 2ohm load, which the amp can't handle in bridged mode.

Using two 4ohm cabs you need to run one each out of the 1/4 jacks, which will output 320w a side at 4ohms.

And speakons or not, the amps seem to be selling okay in the EU ;)

Wiring two 4Ω cabs in series results in 8Ω not two. For that they have to be wired in parallel. This is not what I was advocating.

Paul
 
So I'm looking at getting a Hartke LH1000 and one of my cabs only had a speakon input. This is a silly question but I like peace of mind. Will I have any issues using a speakon 1/4" adapter into the cab? Guitar Center is having that buy one get one free sale today and the LiveWire adapter is one of the items so I figured I might as well grab one.
I had a problem using a Speakon - 1/4" jack adapter with a bridged amplifier. I measured 24v from the un-insulated 1/4" jack input to the AC Ground. I measured after I saw the sparks. Fortunately there was no damage done. I have put a coat of nail polish on the bare metal & keep it as backup.
 
I'm a little confused as to what you are suggesting, BassmanPaul. Could you dumb it down for me a little? :)

Also, I was planning on getting the LH1000 to run two 4 ohm cabs, but now realize I'd only be getting 320 watts to each cab when I thought I'd be getting the 545... How would the amp even operate with 545W @ 2 ohms? The manual says if you're using two 4 ohm cabinets you have to use the amp in dual parallel mode which would only have a 4 ohm load on each channel...
 
I had a problem using a Speakon - 1/4" jack adapter with a bridged amplifier. I measured 24v from the un-insulated 1/4" jack input to the AC Ground. I measured after I saw the sparks. Fortunately there was no damage done. I have put a coat of nail polish on the bare metal & keep it as backup.

In bridge the tip and the sleeve of a phone plug are both electrically hot from ground connected to a different channels outputs. One channel is 180 degrees out of phase with the other. As an example if the amp is pushing 100W per channel each is putting out close to 30V AC. Because they are out of phase that voltage is essentially doubled. That's 60V and the amps barely idling. I'll let you do the math for what the amp will be putting out at its maximum. This is potentially dangerous to you personally and also to the amp. Speakons are the only way to go.

Paul
 
Many players don't understand how bridging an amp works. One channel connects to the speakers positive terminal and the other channel connects to the negative. Because the channels are out of phase by 180 degrees, as the speaker + is driven high the - swings low by the same amount. This translates to up to four times the amps individual channels capabilities. The caveat is that each channel "sees" half the load. For an amp the has a 4Ω minimum per channel you can only bridge into 8Ω or higher. 2Ω per channel you can bridge into 4Ω.

If you are using each channel separately to two cabs then you only get the regular individual power level. If you do this switched to bridge one cabinet will be out of phase with the other leading to severe cancellations.

Paul
 
I'm a little confused as to what you are suggesting, BassmanPaul. Could you dumb it down for me a little? :)

Also, I was planning on getting the LH1000 to run two 4 ohm cabs, but now realize I'd only be getting 320 watts to each cab when I thought I'd be getting the 545... How would the amp even operate with 545W @ 2 ohms? The manual says if you're using two 4 ohm cabinets you have to use the amp in dual parallel mode which would only have a 4 ohm load on each channel...

Isn't the LH1000 2 500w power amps running stereo? Wouldn't that give you 500w @ 4ohms into each 4ohm cab running in "Dual Parallel" mode? I think thats how I'm reading it off page 12 of the Invalid Link Removed.