If one runs one voice coil on a dual voice coil sub will that cause damage to the amp? My brother built a subwoofer enclosure with a tempest sub. He used a 350 Watt plate amp (from apex Jr). Initially he wired the voice coils in parallel to achieve a 4 ohm load. During normal bass passages at reference volume or lower is sub clipped bad. So I recommended that he run just one voice coil at 8 ohm to take the stress off the sub. Well that seemed to help. The sub clipped much less but still clipped. Well his amp developed a nasty hum some months later and then bit the dust. He talked to someone that told him that running the sub with one voice coil killed the amp.
What do you sub experts think? By the way he used the enclosures plans from adire audio, 214 L.
If anything you would damage the sub first. Running the amp only to one voice coil will do no damage to the amp. It sounds like the amp was over driven too much, or the amp was faulty in the first place.
Well, 300W at 4ohm into parallelled voice coils in the Adire Allignment is more than enough to drive the Tempest past it's linear limits. You'd have had to be at extremely high levels of bass (that would have sounded aweful) to clip a 350W amp on that sub.
Running one voice coil on a Tempest drops sensitivity a chunk, doubles Qes, changes it to an 8ohm load and halves the power handling.
Off that amp you should be running the coils in parallel. You also shouldn't have been having clipping problems. My guess would either be a defective driver or amp. Given what the amp is doing now I'd agree with JRace. Do you have access to any other amps to try on the Tempest?
Believe me the amount of volume need to clip the sub wasn't high at all. I have been into Home theater for 7 years and I know acceptable levels of volume. Put it this way. My klipsch KSW-15 kicks the crap out of his Adire setup (15 inch tempest sub) in terms of bass volume at reference volume on Star Wars EP1 . This should not be the case, the klipsch is good but not that good. Okay with all of his speakers including subwoofer calibrated at 75 db at lets say 0 on the master volume (THX setup) his sub would clip at -11 db on the pod race of EP1. Odd, very odd.
Sounds to me (even more now) that the amp fas faulty.
If the box was designed/constructed poorly you would damage the woofer.
If the Sub was defective, there would be little chance that the amp would toast and not the sub (except for maybe blowing the amp right-away).
Something is definately wrong. An Adire Allignment Tempest with 350W WILL utterly destroy a KSW15.
I have a 260L Tempest tuned to just over 16hz with a 6" port powered by an AVA250. At 10dB under reference with the sub a little hot I measured uncorrected peaks of 117dB in the opening battle scene in LOTR (with a rather large room considering how open the floor plan is).
At 10dB under reference on the THX intro to TPM the SPL meter breaks 110dB when the ball explodes.
My sub is pretty close to my DVD player, and when I started to turn the bass up way above the other speakers while listening to Lenny Kravitz's American Woman, the DVD player started to skip before I noticed any real strain on the Tempest.
Well this is all good to know. He returned the amp for a new one. His amp looks just like the ava250 but it's the 350 watt model http://www.apexjr.com/Apexsenior.htm I have the AVA250 running my bass shakers on my home system and I love it. Unfortunately the AVA250 has a smaller foot print so it won't fit the cutout in his enclosure. Also his enclosure was built by a packaging engineer friend of his who did an excellent job, heavy duty joineries and such.
He could build a baffle that attaches to the sub box, that fits the new amp.
Done right it could look great. Don't worry about using up more internal volume if necassary. You will be hard pressed to notice any differnce losing 5-10% internal volume.