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Posted By: colleen EP500 FM - 02/17/05 02:32 AM
I got my EP500 2 days ago. Sounds realy great, after getting rid of the 50 hz hum caused my ungrounded CD player. Sounds great, except with the radio. If the subwoofer is on with the radio, the sound is so muffled that we can't make out anything they say. Any ideas?

MI60
EP500
Denon DRA-685
Posted By: CosmicVoyager Re: EP500 FM - 02/17/05 02:45 AM
colleen,

How is the sub connected to the Denon DRA-685? The Denon is a stereo receiver without a sub ouput connection, or am I wrong ? I might need more info.
Posted By: JohnK Re: EP500 FM - 02/17/05 02:47 AM
Colleen, good to hear that you're enjoying your EP500. Just to clarify, are you saying that the FM tuner on your 685 works fine, but if you turn on the sub something happens to it?
Posted By: colleen Re: EP500 FM - 02/17/05 02:50 AM
After quite a lot of debate with Axiom people and other, I connected the sub to the receiver using A speaker outputs and then connected the 2 mains to the sub.
Posted By: colleen Re: EP500 FM - 02/17/05 02:54 AM
Well, everything sounds terrible, music, people talking. Can't make out anything out of the sound coming out of my main speakers. It happens even when the volume on the sub is turned way down. I just listen to the radio in my car, but it bothers my boyfrend...
Posted By: colleen Re: EP500 FM - 02/17/05 02:56 AM
Sorry, I guess I'm tired. If I turn the power off my sub, the sound is fine when listening to the radio.
Posted By: CosmicVoyager Re: EP500 FM - 02/17/05 03:06 AM
So from the Denon speaker terminals to the EP500 high level input and then out (which connectors on the sub?) to the speakers? Is this right?
Posted By: CosmicVoyager Re: EP500 FM - 02/17/05 03:10 AM
I'm trying to understand how by looking at this picture.


Posted By: Wid Re: EP500 FM - 02/17/05 03:15 AM

Did ya try as JohnK had suggested and run the mains off speaker A then run the sub off of the B.That might be worth a try.
Posted By: colleen Re: EP500 FM - 02/17/05 03:34 AM
There is no sub output on the receiver. I used the "A" speaker outputs on my receiver to go to the high level inputs on the sub. I then ran wires from the same high level inputs on the sub to the two MI60 using banana plugs. All the guys at Axiom told me not to use the "B" speaker outputs on my receiver to connect the sub. They say I would probably have an impedance problem.
Posted By: CosmicVoyager Re: EP500 FM - 02/17/05 03:42 AM
It should work fine. Very strange.
I would give Axiom a ring. If they can't figure it out then see what you think of this http://www.outlawaudio.com/products/icbm.html

The manual see fig 4.
http://pdf.outlawaudio.com/outlaw/docs/icbm_manual.pdf

A few of us around here have them and they work great.

Good Luck!


Posted By: Wid Re: EP500 FM - 02/17/05 03:49 AM
I use an Icbm in my 2 channel set up.I too don't have a sub out from my preamp.It is one of the best pieces of equipment I have ever bought for this application.It is also really easy to hook up.You can get them in B stock for $199.It is perfect for you situation.
Posted By: JohnK Re: EP500 FM - 02/17/05 04:07 AM
Colleen, it's unclear how the difference in connections would possibly affect just the FM tuner(is there no problem when you play a CD with the sub on?), but you should at least try the connection that I suggested to see if there's any difference. Disconnect the M60 wires from the EP500 terminals and instead connect them to the B terminals on the 685 and select both A and B on the 685. Despite what "all the guys" might have said, the input impedance of the sub amplifier is far too high to significantly change the overall impedance when the M60s and EP500 are connected in parallel.
Posted By: colleen Re: EP500 FM - 02/17/05 04:12 AM
There is no problem listening to CD's. I will try to connect my sub on the "B" and let you know what happens. The impedance on the sub is 4 ohms and on the MI60 it's 8 ohms. What would that amount to?
Posted By: JohnK Re: EP500 FM - 02/17/05 04:41 AM
No, Colleen, the impedance of the input to the sub amp is somewhere in the tens of thousands of ohms(the 4 ohm impedance of the sub driver itself isn't relevant). The net resulting impedance when two impedances are connected in parallel is calculated as the reciprocal of the sums of the reciprocals of the two impedances, i.e. 1/total=1/A+1/B. Using for example 16,000 ohms as the sub amp input inpedance, we get 1/8+ 1/16,000= 2001/16,000, the reciprocal of which is 7.996 ohms. Again though, the connections might have nothing to do with the FM problem.
Posted By: donjuanmiguel Re: EP500 FM - 02/17/05 02:41 PM
Hi Colleen,
A couple of us have had similar issues with the 500. In my case, it seemed like from one day to the next my FM reception for some stations weakened. I didn't think nothing of it until I came across a thread here that mentioned possible magnetic interference from the 500. I tested it out and sure enough my reception improved when I powered down the sub. I spoke with Axiom and they have an RF module to correct it. The sub should be arriving today and I'll post results after its been set up.

All-in-all, the folks at Axiom have been very supportive and their customer support is second to none. Keep them informed and they'll help you find the cause of reception problem.
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