Amp Question

[jeffsg4mac]

Did you say that you disconnected the ART clean box and still had the hum? I tried using one of those and it was very noisy. If your amp has 1/4 inch then just go to radio shack and get some RCA to 1/4in adapters and skip the clean box.

Edit: just looked at your manual. You don't have 1/4 in. If you want to skip the clean box then go to your local music store and get some XLR to RCA cables. I am using just that for all my behringers.

These are what I use.

http://www.sweetwater.com/store/detail/XRM305/

 

[Sabresguy]

Thanks for the post but read back a few. The Art box is not the issue. I have it narrowed down to the amp it self(left channel) or the Left main speaker. With no signal going to the amp I shouldn't be getting a hum out of one speaker and not the other unless the one speaker is defect or the amp channel.

 

[jeffsg4mac]

Thanks for the post but read back a few. The Art box is not the issue. I have it narrowed down to the amp it self(left channel) or the Left main speaker. With no signal going to the amp I shouldn't be getting a hum out of one speaker and not the other unless the one speaker is defect or the amp channel.

OK then easy, swap the speakers. If the hum follows then its the speaker, if not then its the amp. Glad you narrowed it down.

 

[Sabresguy]

The left speaker is the problem. The hum did not follow. Brand new speakers, atleast I can return them. I wonder if that would be a tweeter or magnate problem, hum is coming from the left horn.

 

[jeffsg4mac]

The left speaker is the problem. The hum did not follow. Brand new speakers, atleast I can return them. I wonder if that would be a tweeter or magnate problem, hum is coming from the left horn.

If you swapped the speakers and the hum stayed left then it is the amp not the speaker. If the speaker was bad then it would make the right side hum.

 

[Sabresguy]

Freaking confusing. Sorry man just worked an overnight and tired as hell. I get what your saying but I switched the speaker outputs, didn't swap the speakers. So if it was the amp...when I switched the outputs the hum would have followed. If it was the left speaker at default then the hum would stay with that speaker. Correct me if I am wrong on that. And it stayed in the left!

 

[jeffsg4mac]

Freaking confusing. Sorry man just worked an overnight and tired as hell. I get what your saying but I switched the speaker outputs, didn't swap the speakers. So if it was the amp...when I switched the outputs the hum would have followed. If it was the left speaker at default then the hum would stay with that speaker. Correct me if I am wrong on that. And it stayed in the left!

Yes if you just swapped the wires and the speakers stayed put, and the hum stayed left then it is the speaker. And yes it is confusing.

 

[TLS Guy]

Freaking confusing. Sorry man just worked an overnight and tired as hell. I get what your saying but I switched the speaker outputs, didn't swap the speakers. So if it was the amp...when I switched the outputs the hum would have followed. If it was the left speaker at default then the hum would stay with that speaker. Correct me if I am wrong on that. And it stayed in the left!

A passive speaker can not generate hum.

However it may be that the speaker lead, because of length and direction is picking up radio frequency interference.

The reason speaker leads can pick up interference that is played back by the amp, is that the speaker leads feed back the RF into the high gain stages of the amp via the negative feedback circuit. The base emitter junction in a less then stellar amp design can rectify this RF and then it is amplified and sent to the speakers as hum.

Now take one of your speakers put it as close to the amp as possible and connect it with a very short speaker cable and see if that stops the hum. If it does, then your problem is RF interference from the speaker leads amplified via the negative feedback of the amp.

If this is the problem I will tell you how to fix it.

 

[jeffsg4mac]

TLS is right, I did not have time to elaborate because I had to get to work. Is it a hum exactly like an electrical hum or a buzzing or vibration sound. If it is an electrical hum then TLS may have it exactly correct. However, sometimes when a speaker part is failing they can make some strange noises and they can sort of make sounds that sound like a hum but are not. I had a speaker where the spider came unglued and it sounded like an electrical problem but it was the driver. It was not until I pulled out the driver and examined it I found the problem. You could simply have a bad driver in the speaker that is starting to fail.

 

[Sabresguy]

You were right earlier today. The hum switches or follows the left side of the amp. So its either an amp defect or the RF interference. I do not have shorter cables to test that theory. So Friday I move into my house and I will see how things sound there.

 

[jeffsg4mac]

You were right earlier today. The hum switches or follows the left side of the amp. So its either an amp defect or the RF interference. I do not have shorter cables to test that theory. So Friday I move into my house and I will see how things sound there.

Well, that sucks

 

[Sabresguy]

Sending the amp back today!(Tested and has a defect). Since I need to replace the amp I figure why not spend more money lol and go with my original ideal. Any input would be good.
Yamaha 665 receiver (main preouts) to Line Conversion(Art Clean box) to

Yamaha P7000S Dual-Channel Power Amp to

(2) Yamaha S215V Club Series V Speaker

I would just run 2 Channel for Music and Blu ray/DVD.

Any ideals or recommendations would be appreciated!!!

Thanks for all the help Jeff, you seem pretty knowledgeable! Could you take a look at this setup for me and see if it would work.
I could always get rid of the Art box and run Monster Cable DJ Cable Dual RCA to 1/4 from the Receiver to the amp. From looking at the specs on the Dual channel power amp, I believe this would be possible!

 

[TLS Guy]

You were right earlier today. The hum switches or follows the left side of the amp. So its either an amp defect or the RF interference. I do not have shorter cables to test that theory. So Friday I move into my house and I will see how things sound there.

Its the amp then. Case closed. You gave us quite a red herring with your previous few posts!

 

[Sabresguy]

Thanks for your input. It was just really frustrating to have a professional amp for the first time and have a problem. Have heard nothing but good things about Crown. Sucks but I think it's time to go with Yamaha. I have always trusted Yamaha just wanted to save some cash with the Crown.

 

[TLS Guy]

Sending the amp back today!(Tested and has a defect). Since I need to replace the amp I figure why not spend more money lol and go with my original ideal. Any input would be good.
Yamaha 665 receiver (main preouts) to Line Conversion(Art Clean box) to

Yamaha P7000S Dual-Channel Power Amp to

(2) Yamaha S215V Club Series V Speaker

I would just run 2 Channel for Music and Blu ray/DVD.

Any ideals or recommendations would be appreciated!!!

Thanks for all the help Jeff, you seem pretty knowledgeable! Could you take a look at this setup for me and see if it would work.
I could always get rid of the Art box and run Monster Cable DJ Cable Dual RCA to 1/4 from the Receiver to the amp. From looking at the specs on the Dual channel power amp, I believe this would be possible!

May I ask, but why are you using PA speakers, and by the looks of them really dreadful ones to boot?

This is the Harbinger site.

It has the feel of a really Slick Willy site.

Here are your speakers.

There are no meaningful specs given, except that the sensitivity is 100 db, presumably 2.83 volt 1 meter as they are four ohm. So if this is for home use you don't need and amp more powerful then 5 to 10 watts per channel.

They don't quote the 3db point, but typically 15" speakers of that sensitivity, with rolled paper surrounds, roll off around 60 Hz, so I can be certain they are well rolled off by 40 Hz.

The next issue is that the horn is small so you know those 15" speakers are handling the mid range. So there will be multiple cone break up modes, coupled with reflections from the hard surround termination. That will add up to a frequency response that looks like the Rocky Mountains!

Unless you are a a weekend DJ then these speakers are highly unsuitable for listening in the home. If you are a DJ, I would buy different speakers for the home.

Honestly you would be further ahead putting your money into decent speakers and using the amps in your receiver.

 

[Sabresguy]

Take a look at a few posts above. Taking these back and going with my original ideal of Yamaha. As far as why I am going this route. I love music and use to have a pair of yamaha 15's years ago. Music sounded great and 2 channel movies weren't bad. Moreless I wanna have the option to still have the av reciever to connect hdmi and ps3 but connect pro audio. As far as amps...you can't power a speaker that has 600 watt rms with anything less then that power. You can blow the speakers.

 

[markw]

Omg!!!

As far as amps...you can't power a speaker that has 600 watt rms with anything less then that power. You can blow the speakers.

Kid, you've got a LOT to learn. But, by arguing, rationalizing, and disputing every answer you're given isn't the way to go about it. You just waste the respondents time and, after a while, they stop.

But ultimately, what you're heading for is loud, not musical.

Read threads on subjects similar to your issues, other than those you initiate. That's a good way to learn things you didnt even think you needed to learn.

 

[TLS Guy]

Take a look at a few posts above. Taking these back and going with my original ideal of Yamaha. As far as why I am going this route. I love music and use to have a pair of yamaha 15's years ago. Music sounded great and 2 channel movies weren't bad. Moreless I wanna have the option to still have the av reciever to connect hdmi and ps3 but connect pro audio. As far as amps...you can't power a speaker that has 600 watt rms with anything less then that power. You can blow the speakers.

You won't blow the speakers, because with 100 db sensitivity yours ears would be blown long before your speakers in any domestic room, with even a 10 watt per channel amp.

 

[Sabresguy]

Hey I appreciate the help, I don't recall ever disagreeing that I had a problem. I was getting a few different feedbacks and was merely trying to figure it out. As far as I have a lot to learn, I don't disagree with that...but I think we all do lol. Case in point, why be on a forum if you know everything! Wouldn't be on here if I did!

 

[markw]

Hey I appreciate the help, I don't recall ever disagreeing that I had a problem. I was getting a few different feedbacks and was merely trying to figure it out.

No, you were looking for a convenient answer you wanted to hear. Reality doesn't always work like that.

As far as I have a lot to learn, I don't disagree with that...but I think we all do lol.

Yes, but some have more to learn than others.

Case in point, why be on a forum if you know everything!

Two part answer here.

First part: Well, I doubt any of us claim to know everything, but as an aggregate we have many, many years of experience and have picked up quite a bit.

Second part: Dunno why you would want to stay, but maybe we like to help those who truly want to learn?

Wouldn't be on here if I did!

Well, reflecting on the second part of the above answer, I guess we can see what your contributions will be here.