Axiom Home Page Forums General Discussion Technical Questions EP subs sucking life (gain) out of the 350's....

I know mojo talked about this a long time ago, but today I noticed this to be a fact.

If I have the EP600 either daisy chained with my 350's, or if I use a splitter at the receiver it does not seem to matter, the 600 is dropping the dB's by about 6-7dB for each 350.

I thought the Line In and Line Out jacks were just a "pass through" type of connection, but this does not appear to be the case for the EP subs.

I found this out because I tried hooking up just 1 or 2 350s (daisy chained) with the 600 not in the loop. If I calibrate each sub to 75dB's individually, then turn them both on, I get about a 3dB+ increase, which makes sense. However, as soon as I incorporate the 600 into the daisy chain, or have it on its own line split at the receiver, the dB's for the 350's drop about 6-7dB's per the meter.

This explains why I have to have my 600 volume knob so lowwwwwwww (about 6 o'clock) and my 350's about 3/4 cranked to achieve the same dB reading on my SPL meter.

This seems crazy, and is causing habic with me setting up Audyssey. I may call Axiom to see what they have to say..

Randy

I don't see what the big deal is. That is what the gain knobs on the subwoofer are for.

If you run out of gain, it is a big deal. The 350's have to be pretty much maxed out to achieve the same SPL. It is pretty much impossible to calibrate to 75dB's with the 600 in the loop.

Do you frequently change the receivers trim for different sources?

I just talked to Axiom, it appears the output of the EP600 (and I assume 500/800) are great enough that other subs in the mix will require lots of gain to be equal. This can be a bit tricky. As most of you EP owners have realized, you have to keep the gain almost all the way down as a higher setting will require the receiver to be set down as low as -10to-12dB to compensate.

Then, to get the other subs at the same SPL, you have to almost max them out. You can't raise the receiver level to help, becauese this would require the 600 to be lower, and your out of room.

Maybe some day receiver manufacturers will figure out that independent multiple sub preouts are required.

I'm not as educated as others on this forum, but that doesn't seem right to me and would be frustrating.

In order to have seamless bass, you would need three EP600s. Jason, do you think this would apply when adding any other sub i.e. another brand?

No Dr, if you read what I've posted, the problem lies when trying to calibrate multiple subs, to the same SPL as your speakers. I never said that I change levels for different situations. Even the Audyssey setup guy recommends calibrating each sub independantly to 80dB's prior to combining theme and running Audyssey. Currently, this is not possible for me, so I have to use something lower like 70dB's. Anyway, Axiom confirmed my thoughts.

There are a lot of subs on the market Cam, lots with great output ability. I've never heard anyone on other forums having this issue, many people daisy chain subs. Maybe it is just the Axiom design, not sure.

I wonder if it would happen when daisychaining an Axiom sub that you mention with another brand.

The response from Axiom makes sense to me. The EP350 and EP600 will have different input sensitivity ( one will need more gain than the other) due to the amp design. Using them together in a multiple subwoofer setup will ultimately make calibrating more difficult. This is one of the advantages of using identical subwoofers.