Crosstalk in Analogue Amplifier?

aldente

Hi, I have a question on analogue amplifiers, which seems rather strange to me, and I would like to find out whether it is common or normal among them.

There is a crosstalk you can hear on an analogue amplifier which I bought recently as brand-new. It has input connectors for phono, tuner, CD, CDR, and DVD/Aux. When a music source is connected to the CD input, and no other input is used, the sound of the CD input is heard on the other inputs at a high volume.

Does anyone have any idea of whether this is common?

kao123

aldente wrote: »

Hi, I have a question on analogue amplifiers, which seems rather strange to me, and I would like to find out whether it is common or normal among them.

There is a crosstalk you can hear on an analogue amplifier which I bought recently as brand-new. It has input connectors for phono, tuner, CD, CDR, and DVD/Aux. When a music source is connected to the CD input, and no other input is used, the sound of the CD input is heard on the other inputs at a high volume.

Does anyone have any idea of whether this is normal?

Hi aldente,
I did have this issue years ago when plugging a philips CD player into an AUX port on an old sony amp (can't remember the model) but it turned out to be the philips cd player causing the issue in the end.

Are you connecting a CD player to the CD input or another device?,
might be worth trying another source into the CD input to see if it is the actual input that is the problem....

Hope this issue isn't on the PM6003 .... I'm still planning on buying one soon!

cheers

aldente

This happens on PM6003...:eek:

iTunes music is streamed via DacMagic to the CD port of PM6003, and there is no input coming or no cable connected from any other source. Now, if you switch to another input channel and turn up the volume, you hear the sound of the iTunes music on the CD port. The crosstalk level is largest on the tuner port.

The same problem occurs with a Blu-ray player connected to the DVD/Aux port of PM6003, again, no input or no cable from any other source. If you switch to another input channel and turn up the volume, you hear the sound from the BD player.

I reckon this is a fault. To explore further, a search on the web brought me to an excerpt from a book titled "Audio Power Amplifier Design Handbook, Fourth Edition", which goes like this:

Crosstalk in Amplifier Output Inductors

When designing a stereo power amplifier, the issue of interchannel crosstalk is always a concern. Now that amplifiers with up to seven channels for home theatre are becoming more common, the crosstalk issue is that much more important, if only because the channels are likely to be more closely packed.

http://www.globalspec.com/reference/22139/203279/Crosstalk-in-Amplifier-Output-Inductors

kao123

I have to say I've never heard of it being that bad.

There's actually a hifi shop here in Limerick that stock them if I am in going into town this weekend I'll bring my iphone and a lead and I'll plug it and see if I notice anything.

Another thing to try would be another power source, i.e. plug the amp in in another room, or dare I say it, try a mains conditioner, I know Maplins do one for about €40. - I am not convinced about this but it can't hurt to try if you can get a mains conditioner that is, some people swear by them so maybe there is something in it.


I am surprised that the PM6003 is doing this after the glowing review it got in WHF and on a few other sites.

If you got it from RS then am fairly sure they could try to replicate the problem with one instore.

Then again it might be a plain and simple faulty unit.

Let us know how you get on with it.

Kao123

aldente

kao123 wrote: »

I have to say I've never heard of it being that bad.
There's actually a hifi shop here in Limerick that stock them if I am in going into town this weekend I'll bring my iphone and a lead and I'll plug it and see if I notice anything.

Hi kao123,
That is interesting, please let me know what you get from auditioning it in your local shop.

aldente

kao123

Hi aldente, I was in the shop on Saturday but could only get a quick listen to the PM6003, I couldn't try any fancy testing, it was connected to a CD6003 and I flicked through the other inputs while it was playing and I didn't notice any crosstalk from the cd player.

I couldn't really put it through it's paces though, but I can say I didn't hear any cross talk at all.

Think you might need to call RS and see what they can do about it?
Did you try any other power sources?

Am very interested to see how you get this resolved

aldente

To summarise, I have had to swap all my Marantz units out due to audio crosstalk on SR6004 and PM6003 and a scar on the front panel of BD7004 that they arrived with.

Richer Sounds were very swift to arrange for a swap-out, professionally and apologetically. So I am happy and hopefully the replacement will arrive in 2 to 3 weeks.

I understand that things like this can take place. However, I am a bit concerned about quality control or design management that Marantz put in place. I hope that they will not be risking the good reputation they have earned over the years. I want companies that produce products with a vision to survive !!

kao123

Wow I have to say I'm a bit shocked to hear that, I am a big Marantz fan and have had a few of their amps over the years and my current SR6003 is running absolutley top notch. Although I think I'll have to give it a good test tomorrow when the kids aren't in bed.

At least you know that the guys in RS will take care of you.

It is a bit concerning that it is happening on both the SR6004 and the PM6003, one amp you could understand but two models is a bit worrying.

I'd like to think that the fact the PM6003 got 5 stars from whf and lots of other good reviews means that it is a top of the range model (for it's class) and that the build quality will be sustained to keep it on top.

Hope you can survive the 2 to 3 weeks with your kit....

kao123

kao123

Hey aldente, just curious if you got your replacement kit? if you have is the crosstalk issue gone now, I've been randomly checking my SR6003 ever since you highlighted the issue and so far I haven't had any problems.

aldente

I'm still waiting for PM6003 to arrive. Well, if no crosstalk is encountered after several checks on your unit, I reckon it's good.

ZENER

Hi all ! A bit of perspective is needed here I think and a correction in terms !!

Firstly, You say you can hear the audio from the CD when another input is selected. I'm assuming this is when you crank the volume control all the way up ? This isn't unusual in an amplifier. My Denon does this as does an AudioLab amplifier I own. With only a cd player connected this means all the other inputs are open and floating ant therefore susceptible picking up stray signals - perform your test again with say the Aux input except use 2 phono plugs shorted. This will ground the inputs minimising the effect. Do this for all unused inputs if you like ! Or better still any other sources to the amp should be stopped or turned off when not in use !

Secondly, Crosstalk refers to signals from the channels of a single source - for example the signal from the Left channel of the CD Player being heard in the Right channel. Plug just the Left connector from your CD Player into its connector on the amp but leave the Right connector unconnected. Now turn the Balance control all the way to the Right - any signal you hear is called crosstalk.

Hope this helps.

Ken

aldente

ZENER wrote: »

Hi all ! A bit of perspective is needed here I think and a correction in terms !!

Firstly, You say you can hear the audio from the CD when another input is selected. I'm assuming this is when you crank the volume control all the way up ? This isn't unusual in an amplifier. My Denon does this as does an AudioLab amplifier I own. With only a cd player connected this means all the other inputs are open and floating ant therefore susceptible picking up stray signals - perform your test again with say the Aux input except use 2 phono plugs shorted. This will ground the inputs minimising the effect. Do this for all unused inputs if you like ! Or better still any other sources to the amp should be stopped or turned off when not in use !

Secondly, Crosstalk refers to signals from the channels of a single source - for example the signal from the Left channel of the CD Player being heard in the Right channel. Plug just the Left connector from your CD Player into its connector on the amp but leave the Right connector unconnected. Now turn the Balance control all the way to the Right - any signal you hear is called crosstalk.

Hope this helps.

Ken

Zener, thank you for your comment.

This problem was not experienced by my old analogue amp and others in the 90's. It may be up to the owner how to interprete this problem since they can avoid it if they keep the volume lower. Nowadays, however, it is common to have multiple media sources on simultaneously in a house, which is an attractive feature of yokes like AV receivers and streamers. Therefore, being confined to a single source only, and also because of my experience above mentioned, I would only feel miffed. I suppose that the "low cost, low quality standards" phenomenon in the economy allowed it to occur.

Regarding the terminology, do you have any idea of an expression that describes this problem in hifi audio systems? I may be wrong but quoted "crosstalk" because the symptom is equivalent to what crosstalk means in the telecommunications in which I have been working. That is a signal floating from one circuit to another - not about the same source, obviously. This crosstalk manifests itself for example in a telephone conversation, where you can hear a conversation of another caller whilst you are on to your person. It could be caused on the transmission cable but also on the printed circuit board. So similar.

I am not dismissing your reply, but just wanted you to know why I referred the problem to "crosstalk".

aldente