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Sunn Musical Equipment => Q & A => Topic started by: BASSPLAYER on December 04, 2020, 11:20:34 am

Title: New Sunn Coliseum Slave Amplifier- what speaker cabs can I use ?
Post by: BASSPLAYER on December 04, 2020, 11:20:34 am
Hello fellow forum members. I am a new member, that just took ownership of a Coliseum Slave amplifier. It was given away free, and nothing known of working condition.I know it is a power amp that can be used to power more speakers, but I want to use it with a pre-amp to play my bass guitar. I tried out the amp after bringing it  home. I powered it up on a dim bulb tester, and everything was good. Then plugged my bass into a Sansamp pre and plugged  a 1x10- 8 ohm speaker cabinet into one of the 1/4" jacks on the back. It played fine, but had a scratchy pot. It didn't seem very loud to me, but I thought it was because of the 8 ohm cab. I didn't want to plug into a 4 ohm cab without knowing the speaker output layout. As it looked like there was a extra jack that was added. And the last time I plugged a 4 ohm cab into a new to me solid state amplifier, I let out the magic smoke. I took the case cover off, cleaned the pot and jacks and took a few pictures of the speaker output jacks. It looks like all the speaker outputs are wired in parallel. But the one jack that looks like it was added, looks to have a coil and resistor /cap ??? I have enclosed pictures, and hope somebody will set me straight on what size cabs I can safely use with this amplifier.
Title: Re: New Sunn Coliseum Slave Amplifier- what speaker cabs can I use ?
Post by: loudthud on December 05, 2020, 12:05:37 am
The Coliseum power amps can drive a 2 Ohm load. That's four 8 Ohm or two 4 Ohm cabinets. The coil and resistor combo is a standard part of the power amp. It prevents oscillation with a capacitive load like a piezo tweeter or long coax speaker cables.
Title: Re: New Sunn Coliseum Slave Amplifier- what speaker cabs can I use ?
Post by: BASSPLAYER on December 21, 2020, 08:55:24 pm
Just got back in town. Thank you LOUDTHUD  for your reply. I will now plug into a 4 ohm cab, and see if I can get more volume from this amplifier. Wasn't very loud with a 8 ohm cab. And by that, I mean it never got stupid loud. Not that I play at stupid loud volumes, but would like to know that I could if I wanted.
Title: Re: New Sunn Coliseum Slave Amplifier- what speaker cabs can I use ?
Post by: BASSPLAYER on December 21, 2020, 09:06:49 pm
Another question from a inexperienced Sunn Slave owner. There are five - 1/4" jacks on the back of the amplifier. Three in the center area of the amp, and two to the far right of the amplifier[ as you are looking at the back of the amp]. If I can only use a maximum of four 8 ohm cabs, why are there five speaker output jacks ????
Title: Re: New Sunn Coliseum Slave Amplifier- what speaker cabs can I use ?
Post by: loudthud on December 31, 2020, 05:49:00 pm
Compare the attached photo to your amp. The red arrows point to text on the back of the amp that explains the function of the jacks that are the subject of your question. If that piece is missing from your amp, look around on the internet for a clearer picture.
Title: Re: New Sunn Coliseum Slave Amplifier- what speaker cabs can I use ?
Post by: BASSPLAYER on January 07, 2021, 11:53:21 am
Thank you, again, Loudthud. Hope your holidays were nice. Happy New Year !