Peavey VK 100 need less on 1 cabinet

[elwoodm]

hello to all new to the forum searched for this problem i am having but did not find solution. vk 100 head powering a b52 at-412a 480 watt rms top and line 6 240 watt rms bottom can run at 4 ohms or 16 on both. i need to lower the volume on the b52 top cabinet because it is soooo much louder than the line 6. the outs from the amp are paralleled and 100 watts/40 volts rms. anything that i could put in the line going from amp to speaker that would not effect impedance and bring the power down so i can hear my line 6 bottom cab

[The Dude]

Firstly, welcome to the place!

My first question would be, "How are you running it now?". At what impedance are you running the cabinets and head. Are you running both cabinets at the same impedance and is that matched to the head? Cabinets should be 16 ohms and head should be set to 8.

[elwoodm]

the top and bottom cabinets have been run at 16 and 4 ohms they can be set to either. i was under the impression that the amp would need to be set at the ohms the cabinets were set at. my amp the peavey can be set at 4 8 or 16 ohms the speakers can only be set at 4 or 16 ohms mono. do not know how running amp at 8 ohms with cabinets set at 16 would lower volume on top cabinet so i could hear the bottom cabinet better?? just need less juice going to top cabinet without doing anything that would effect the sound or the amp thanks for your reply glad to be here and learn from all of you hope i can contribute to this great forum

[The Dude]

The two cabinets are paralleled, so the amp will need to be set at the equivalent of the paralleled load. Two 16 ohm cabinets in parallel = an 8 ohm load.

If one cabinet is substantially more efficient than the other, you could run the less efficient cabinet at 4 ohms and the other at 16 for a total load of 3.2 ohms, which is close enough to 4 ohms on a tube amp(so you would run the amp at 4 ohms). This might take you too far the opposite direction, but you can certainly try it. The 4 ohm cabinet will draw more current since its impedance is lower.

[elwoodm]

this something i can try i have the amp open now trying new pre amp tubes will be able to see if the power tubes start to get too hot. i will use my meter to see what i get with the cabinets set to 4 and 16 ohms. i was so hoping to just put a volume knob in the line but of course that would be dreaming ha ha. going to give this a try let as we say in the south yall know how it turns out thanks again

[elwoodm]

well the line 6 cabinet is set at 4 ohms and B52 set at 16 ohms VK 100 set at 4 ohms everything is running cool. the B52 is not over powering the stack anymore but you can tell the line 6 is getting more of the power now. the low notes are sounding a lot more powerful through the line 6 and the B52 has less mid range. this test has been on clean channel with the texture set on class a low power next test will be lead channel hope all goes well. thanks the dude it is working just wish i could make a volume knob to stick between the amp and speaker to simmer the B52 down back to playing yall

[g1]

You would need a power attenuator to do that. It should be rated for at least as much power as the cabinet is rated for.

[elwoodm]

that could be put in the line from the amp to the speaker but would not change the impedance of the cabinet and have a pot to take away or give what you need to just that cabinet. is this also called a power soak or is that something different i have seen negative things about attenuators saying they are hard on your amp just to control volume to the cabinets and keep the amp wide open. i will look into this thanks

[The Dude]

There are a couple of other possibilities here.

1) One of the cabinets has a blown speaker. If this were to happen 2 of the speakers wouldn't work in 16 ohm mode. Any non working speakers will function as passive radiators. They might sound like they are working, because of air movement in the cabinet, but they will be out of phase with the working speakers.
2) Somebody replaced some speakers with speakers of the wrong impedance.

I would first use a meter to check the actual impedance of the cabinets to make sure all of the speakers are hooked up and impedance is correct. I might also battery test the speakers and visually make sure they are all moving the same direction.

[elwoodm]

have been inside of both cabinets all speakers check out its just the B52s were made to peel paint off the walls and the line 6 are more for normal good sounding on clean and mid gain. what you said to do works great on the clean channel with lower power on texture but if i were to go to lead and full power ab on texture the line 6 is going to get too much on the low notes. the amp has been on for maybe 5 hours in 4 years bought brand new line 6 is new just bought B52 is 3 years old not played much. just need a volume knob on the B52 or some pillows in front of it now that is an idea that take's me back to college day's playing in the dorm late at night