Amp Question

[Sabresguy]

Running pre outs to stereo converter to amp to speakers. Question is I have an XLS 802D crown amp that pushes 800 per channel at 4 ohms. I get less hum when the level controls are down. Correct me if I am wrong cause I am new to pro audio. the level controls have nothing to do with wattage correct. For example if I have the level controls set to 1/4 with less hum that doesn't mean I am getting 1/4 the wattage right? Just don't wanna ruin the speakers!

 

[highfigh]

Why are you using a stereo converter and what brand is it? What speakers are you using?

If you hear hum, you have wiring issues, like a ground loop or an open ground.

The controls on an amp are for adjusting the input sensitivity and unless your input is extremely low voltage, you should be able to get full power at a lower setting but if you're using a consumer grade source, it's doubtful that it's providing the signal level the amp was designed for.

 

[markw]

huh???

What is a "stereo converter"?

 

[Sabresguy]

The stereo converter converts the unbalanced signal to a balanced signal. I only get a small hum when with a beginning of a track that doesn't have much audio to start. Think I found my answer. A hum eliminator they are called but if anyone has input to this I would appreciate it

 

[tcarcio]

Make sure you have everything plugged into the same circuit. It could cause a ground loop if you don't.

 

[highfigh]

The stereo converter converts the unbalanced signal to a balanced signal. I only get a small hum when with a beginning of a track that doesn't have much audio to start. Think I found my answer. A hum eliminator they are called but if anyone has input to this I would appreciate it

Calling that a 'stereo converter' isn't correct, although it may have two channels. It's an impedance-matching device. What is the brand and model of that?

You have a ground loop and several methods exist to eliminate it.

 

[WaynePflughaupt]

Running pre outs to stereo converter to amp to speakers.

You’re running pre-outs from what?

The stereo converter converts the unbalanced signal to a balanced signal.

What are you using to accomplish the conversion?

Regards,
Wayne A. Pflughaupt

 

[Sabresguy]

Hey guys sorry it took me awhile to get back to this. I am running a Yamaha 665 reciever. Pre outs to a ART CleanBOX Two Way Stereo Converter
I am then running XLR's to from the converter to a Crown XLS 802d Amp. Then from the Crown to (2) Harbinger HX152 Dual 15. I have PS3 and a CD player hooked up along with a a few HDMI fed outs. I have stripped the system apart and with no fed to the amp I still get a hum with just the amp and speakers connected. I was thinking I have a ground loop with the amp and need to get a power conditioner for it.

 

[TLS Guy]

Hey guys sorry it took me awhile to get back to this. I am running a Yamaha 665 reciever. Pre outs to a ART CleanBOX Two Way Stereo Converter
I am then running XLR's to from the converter to a Crown XLS 802d Amp. Then from the Crown to (2) Harbinger HX152 Dual 15. I have PS3 and a CD player hooked up along with a a few HDMI fed outs. I have stripped the system apart and with no fed to the amp I still get a hum with just the amp and speakers connected. I was thinking I have a ground loop with the amp and need to get a power conditioner for it.

A power conditioner will not stop a ground loop. If you have hum with just your speakers connected to the amp, and no input to the amp, then your amp is defective and has a major problem. You can not get a ground loop unless something else is plugged into the amp that is also grounded.

 

[Sabresguy]

The Amp is new and the hum or buzz is only present if I turn the gain up. No input connected

 

[markw]

The Amp is new and the hum or buzz is only present if I turn the gain up. No input connected

IF you're saying the only thing connected to the amp is the speakers, it's the amp.

Either it's part of the design and you learn to live with or it's a defect. If it's new, you have several options open to you.

It's your move.

 

[Sabresguy]

Just called Crown they were pretty cool. Got three years of coverage. I live in an apartment and just bought a house and move in next week. Just wanted to get this stuff and see how it sounded. The crown tech thinks it's the apartment. So when I move in I will see if I get the hum with nothing but the speakers hooked up. He brought up a good point that with apartments you never know how the wiring is configed. So will just have to wait and see.

 

[markw]

They may be "cool", but I don't buy his explanation.

 

[TLS Guy]

They may be "cool", but I don't buy his explanation.

Nor do I. He was blown off.

OP you can do a definitive test. Get a couple of input plugs and short the live to ground, so the inputs are grounded out. Then turn up the gain. If you hear any hum louder, than heard by putting your ear to the speaker, then that amp needs to go back.

If they all hum they are lousy. If yours is the only one that hums then it is defective.

You house AC will no interfere with this test. It is simple and for your protection you need to do it right away.

 

[Sabresguy]

Very odd. I turn the right gain all the way up and like you said I have to go up to the speaker to hear it. About half way on the left gain I can hear it in the left speaker.

 

[TLS Guy]

Very odd. I turn the right gain all the way up and like you said I have to go up to the speaker to hear it. About half way on the left gain I can hear it in the left speaker.

Then you almost certainly have a defective amp, but ground out the inputs to make sure.

 

[Sabresguy]

Same results. Music sounds freaking great on it but certain songs bring the hum if the song or movie is not very loud

 

[Sabresguy]

Kinda bummed cause it sounds great! stripped the system to see if I had a ground loop and it starts with the amp dam it!!!

 

[TLS Guy]

Kinda bummed cause it sounds great! stripped the system to see if I had a ground loop and it starts with the amp dam it!!!

An amp with a hum does not sound great. It is awful and annoying. Send the POS back now.

 

[Sabresguy]

I was just messing with somethings. I was playing a song that starts with guitar on the right main and when everything comes in, both speakers go. Meanwhile when the song starts you hear the hum in the left speaker until music comes in. I switched the speakers so the left would start off and right would have nothing. NO hum when I switch with the right now playing nothing to start. The left has hum over the guitar. So could I have a problem with the left speaker or you still think it would be the left channel of the amp?