Problems with the amp

[davidebond]

Hi. I purchased a JDS Atom Lab for a Sennheiser HD 650 and a Topping dx3 pro. I put the volume at its maximum in Foobar2000, in Windows 11, in the dac, I use the gain and put the volume at 40% in the amp and nevertheless the sound Is confuse and faible. If I plug the headphone directly in the dac the sound Is powerfull and the definition perfect. Any detail Is clear and audible.

Why do I experience this with the amp? A not good RCA cable?

Thanks and best,

Davide

 

[Leiker535]

Either a faulty RCA or a faulty connection at the Atom. Plug the headphones all the way in on the Atom and try moving the connector (jank it a bit) on the Atom and see if the sound changes. If it does, you have a faulty unit and should send it to JDS.

 

[solderdude]

At the same volume there should be no audible difference between the DX3Pro and Atom.

When there is either the amp (or the headphone connector inside) or the interlink cable is faulty somehow.

 

[Sokel]

What mode the DX3 is working at?

 

[DVDdoug]

If I plug the headphone directly in the dac the sound Is powerfull and the definition perfect. Any detail Is clear and audible.

So, you probably don't need the amp.

...Sorry if this is a dumb-obvious suggestion but make sure the DAC is plugged-into the amplifier input, not the output.

 

[bodhi]

So, you probably don't need the amp.

This would be the famous ticket.

The amp in DX3 Pro should sound just the same than Atom, it might even measure better but it doesn't matter of course.

 

[davidebond]

To @DVDdoug : I am sure to have plugged correctly the RCA cable. The mode Is line in order to listen to the amp and not to the dac. I am sure that the dac doesn't Need the amp at this point.

 

[JaMaSt]

I put the volume at its maximum in Foobar2000, in Windows 11,

Not necessarily going to answer your question, but are you feeing the Topping from your PC with USB?

 

[davidebond]

The dac Is connected via USB to the PC and via RCA with the amp. I listen from the amp.

Thanks.

 

[Sokel]

To @DVDdoug : I am sure to have plugged correctly the RCA cable. The mode Is line in order to listen to the amp and not to the dac. I am sure that the dac doesn't Need the amp at this point.

If you have plugged to right input (RCA in) and at the right mode on the DX3 and still don't work just pack it and send it back,something has gone wrong with it and there is danger for your headphones from now on.

 

[davidebond]

To @Sokel : thanks. I'll follow your suggestion.

Best,

Davide

 

[MAB]

The dac Is connected via USB to the PC and via RCA with the amp. I listen from the amp.

Thanks.

Do you have another source? A CD player, a tuner, a TV set with audio out, a phone or computer with a 3.5mm audio out:

Give it a try with a different source.
Try a different cable with that different source. Try the 3.5mm input.
Make sure to select the RCA vs. 3.5mm source using the switch on the front panel.

I will say, this was an unnecessary purchase unless you wanted another amp that sounded the same as the amp in the DX3 with almost exactly the same power. If you did want another amp, this seems like a good one and should work great and shouldn't be giving you such problems.

 

[JaMaSt]

in Foobar2000, in Windows 11, in the dac, I use the gain and put the volume at 40% in the amp

Not being very familiar with Foobar, but in this setup, you can adjust the volume at the PC, at the DAC and at the Amp?

 

[threni]

Not being very familiar with Foobar, but in this setup, you can adjust the volume at the PC, at the DAC and at the Amp?

Not too familiar with Windows but is it possible to alter the volume at both the app and the OS level? If so, check both are on max. If you're using a DAC via USB ideally you'd somehow tell foobar and/or windows "leave this signal alone - pass it to the USB as-is".

 

[Sokel]

Not too familiar with Windows but is it possible to alter the volume at both the app and the OS level? If so, check both are on max. If you're using a DAC via USB ideally you'd somehow tell foobar and/or windows "leave this signal alone - pass it to the USB as-is".

As long as the source is DX3 who is playing fine the problem is down the road,so...

 

[davidebond]

To @MAB : I'll test It. I set the volume at the maximum both in Foobar2000 and in Windows 11 via the audio preferences.

 

[davidebond]

I wrote to JDS Lab.

 

[JaMaSt]

I wrote to JDS Lab.

Maybe try and removing the DAC from the setup. Connect the Atom with a 3.5mm male-to-male directly from your computer's headphone port or rear port. If the Amp sounds good, straight from the computer, that should establish that the Amp is fine.

 

[davidebond]

I believe that the dac Is fine, but I thought It were more powerfull and the gain was more High.

 

[JaMaSt]

I believe that the dac Is fine, but I thought It were more powerfull and the gain was more High.

Maybe I'm confused what your exact issue is? Below you say the DAC sounds great when listened to directly.

If I plug the headphone directly in the dac the sound Is powerfull and the definition perfect. Any detail Is clear and audible.

Why do I experience this with the amp? A not good RCA cable?

My post suggested to run the Amp directly from the computer, to determine if it sounds as good (or the same) as the Amp when run through the DAC.