Direct D50s RCA to 3.5mm advisable?

[lecter255]

Some context
Headphones: HD6xx and Sundara
DAC: Topping D50s
Amp: JDS Atom
Pre-amp: JDS Subjective 3 (Usually in bypass mode)
Genre: Mainly Classical Music
Goal: outputting at the most accurate quality. Volume not a limiting factor

Hi folks,

There is a lot of talk about needing an Amp to get the full benefit out of headphones like HD6xx and Sundara (I have these two). However, I can easily reach comfortable listening level without maxing out the output of the Topping D50s using a RCA to 3.5mm short cable. I have never listened to a whole classical piece on max D50s volume because it's too loud for me, on both headphones.

My question is, is there measurable improvement in signal/sound quality if I add JDS Atom to the chain? My first thought would be no, because that would be adding an extra hop and potential distortion. If there is any noticeable distortion from D50s it would just get amplified by the amp. But I haven't come across a single audiophile who doesn't say something along the lines of "o you need a good amp to open up these headphones". Is there any measurable data to back this up?

TLDR: If the DAC is outputting a volume that is more than enough for me, can there be any objective/measurable improvement by adding an Amp to the chain? I can't say I have heard a definitive difference, but maybe the difference needs to be highlighted to me so I notice. Also hard to volume-match without specific equipment.

 

[Jimbob54]

I can't find them but this has been asked before. The RCA have far higher output impedance than a modern headamp. Such that, depending on the nature and impedance of the 'phones used, might cause undesirable frequency response.

 

[Cahudson42]

there be any objective/measurable improvement by adding an Amp to the chain

Yes.

As mentioned, the Line Out of the D50 is designed to drive a high impedance input, not a low impedance headphone.

Now it so happens that your headphones are planar magnetic, which are relatively insensitive to modified frequency response when connected to a high impedance source.

Nonetheless, think of your connection as a voltage divider, with the headphones getting 'the short end of the stick' with the D50 getting the bulk. At the very least, you are missing out on headroom and dynamic range.

I have HE400i. While they 'work' on low power dongle and phone devices, there is a very noticeable lack of bass and bass 'punch', as well as dynamic range - when compared connected to my Liquid Spark. So much so that I returned ES100 and BTR3 because of it.

 

[Vincent Kars]

I can't find them

Probably this one: https://www.audiosciencereview.com/...adphone-to-the-rca-output-of-a-pre-amp.11707/

Impedance of the amp should be substantially lower than the impedance of the headphone.

 

[Jimbob54]

Probably this one: https://www.audiosciencereview.com/...adphone-to-the-rca-output-of-a-pre-amp.11707/

Impedance of the amp should be substantially lower than the impedance of the headphone.

Cheers

 

[lecter255]

Ok. I guess one of the benefit of having high impedance headphones and low sensitivity planars is so they are less susceptible to distortion, but of course also means they are harder to drive, but that isn't an issue for me because I don't listen at very loud levels.

Concerning lack of bass when connected through a dongle to the phone or driven by a phone headphone jack, I can understand the tiny amp/dac in there may not be great and will thus have high noise floor or distortions at various frequencies, even if the level isn't maxed out.

Ok, now I have my D50s going to JDS Atom. Now, should I 1) keep the volume on the JDS Atom at/close to max on low gain (for least distortion) and adjust the volume using the D50s? Or should I 2) max out the volume level coming out of the D50s and adjust volume on the JDS Atom? I would think it's better to let the dedicated Amp do most of the amplifying, so probably option 1?

 

[Cahudson42]

I would try option 1 first. Seems the D50 may have have a pretty high output capability. No need to chance overdriving the Atom..

 

[Jimbob54]

Ok. I guess one of the benefit of having high impedance headphones and low sensitivity planars is so they are less susceptible to distortion, but of course also means they are harder to drive, but that isn't an issue for me because I don't listen at very loud levels.

Concerning lack of bass when connected through a dongle to the phone or driven by a phone headphone jack, I can understand the tiny amp/dac in there may not be great and will thus have high noise floor or distortions at various frequencies, even if the level isn't maxed out.

Ok, now I have my D50s going to JDS Atom. Now, should I 1) keep the volume on the JDS Atom at/close to max on low gain (for least distortion) and adjust the volume using the D50s? Or should I 2) max out the volume level coming out of the D50s and adjust volume on the JDS Atom? I would think it's better to let the dedicated Amp do most of the amplifying, so probably option 1?

Personal preference is: Set DAC to full output, turn Atom up to loudest you would ever want to go in a listening session then back the D50 down to comfortable level. Does it have a remote? If so, even better as you can then easily nudge volume up and down to taste during your session.

 

[Jimbob54]

I would try option 1 first. Seems the D50 may have have a pretty high output capability. No need to chance overdriving the Atom..

I cant see what the original D50 was but I think the D50s is 2v nominal so shouldnt clip the Atom.

 

[VintageFlanker]

However, I can easily reach comfortable listening level without maxing out the output of the Topping D50s using a RCA to 3.5mm short cable.

You should not do that. As some already said, line out output impedance is far higher than headphone outputs (sometimes kilo ohms) and will mess with frequency response of any headphones at this level...

Atom will bring not only more power (needed or not) but near-1ohms output impedance needed for any headphones or IEM.

 

[lecter255]

Personal preference is: Set DAC to full output, turn Atom up to loudest you would ever want to go in a listening session then back the D50 down to comfortable level. Does it have a remote? If so, even better as you can then easily nudge volume up and down to taste during your session.

Yea it comes with a remote Yea this seems reasonable. Not maxing out any one component, where distortions usually happen.

Ok one last thing. I can choose the output rate and bit depth on my Macbook Pro. Should I set it to match the source or just max it out at 32-bit at 768kHz?

 

[Jimbob54]

Yea it comes with a remote Yea this seems reasonable. Not maxing out any one component, where distortions usually happen.

Ok one last thing. I can choose the output rate and bit depth on my Macbook Pro. Should I set it to match the source or just max it out at 32-bit at 768kHz?

I only do simple questions

If there is a match source button may as well go with that. not sure many round here put much stock in upsampling. Have a search, that's been asked and answered a few times.