WGS Reaper Power Handling

[WaltK]

I tried posting this on the WGS forum but I think they may be having issues because it doesn't go through and they have had no new posts since 9/30. Sorry for the long post below but I'm trying to get all the info out there.

I have a 30 watt WGS Reaper paired with a 65 watt WGS ET-65 in a 2x12. They are both 8 ohm speakers wired in series for a total impedance of 16 ohms. This combo should give me a watt rating of 60 watts by multiplying the lowest speaker rating by the number of speakers, in this case 2x30 =60.

I've used this cab with 50 watt heads and my Class 5 without issue. I recently picked up a MOSFET 3210 with the matching 1966 cabinet. The amp works flawlessly through the 150 watt, 8 ohm cab. The MOSFET manual states that at 16 ohms the head will deliver 50 watts to the load (it is rated 100 watts into 4 ohms). My 2x12 is rated at 60 and is connected 16 ohm so I should be safe. It doesn't appear so. I hooked up the head and on the boost channel with the gain at about 7-8 and the master around 3, (loud but not house rattling)I started smelling something cooking. I shut down immediately and let things cool down. I did not detect the burn smell in the head so i assume it came from the cabinet. I hooked the 3210 to the 1966 and it worked fine. Then I hooked up my C5 to the WGS cab and both speakers are still working.
I've spoken with WGS and they think that the MOSFET might be delivering really high peak current and that is what caused the overload. I also emailed Marshall and they confirmed the output of the 3210 as 50w rms at 16 ohms. I really like the WGS combo with this amp but I'm afraid to connect back up to it. From the specs everything should be safe. Does anyone know of some checks I can do on the speakers? Am I missing something in my calcs? Any suggestions are appreciated.

[bluesson]

I belive you can have a fair amount of power peaks from such amplifier, more than two times the "musical" power rating. In such circumstances the Reaper is first to bite the dust due to lower power rating.

[WaltK]

Problem solved. I guess you could call it teacher error. Over the summer my nephew and I were running each speaker single just to hear difference between the ET-65 and Reaper with different amps. Well when buttoning the cab back up I had my nephew reconnect them in series, I was showing him how easy it was to change speakers for when he was back at home. I should have opened the back of the cab before posting my earlier question. Looks like when he connected up the ET65 he put both leads on the negative terminal, it has 2 spade connections for both positive and negative. So, the 65 was never in the circuit and I was running the Reaper alone at 8 ohms and 30 watts, way under the 80 watt spec of the amp (rated at 80 into 8 ohms). I moved the leads and it works like a champ. Moral of the story, never assume. I should have checked before closing up the cab. Great teacher huh?