Connect Scarlett 2i2 to L30 ii amp

[RoyK]

Hi everyone!

Being new to the premise of audio technicalities, I thought it'd be a good idea to post this question to some more knowledgeable people

Recently, I got myself a pair of Hifiman Ananda Nano headphones to plug into my Scarlett (2i2, 3rd gen). I got recommended to buy a headphone amp (Topping L30 ii) to drive them instead, so I bit the bullet and went for it. Currently, from input to output, we have PC > 2i2 > L30 ii > Headphone. The connection between the 2i2 and the L30 ii is done via the 2i2 line outputs to L30 ii (RCA) inputs, through a dual 1/4 inch TS to dual RCA Stereo cable.

Now, I don't really hear a difference as to plugging my headphones into the 2i2 headphone jack. I was wondering whether anything is wrong in the system as I have it, and/or how the volume levels should be set on PC/DAC/AMP correspondingly? Thanks in advance!

 

[staticV3]

Hi @RoyK! Welcome to ASR.

Please read this post and the ones below it: https://www.audiosciencereview.com/...30-ii-review-headphone-amp.36027/post-2521893

A lot of similar ground is covered there.

 

[staticV3]

TL;DR

1/4" to RCA adapters are a bad idea.

A dedicated headphone Amp for the Ananda is unlikely to make a difference.

If the Scarlett plays loud enough for your needs and there's no audible distortion, then you're getting the full sound experience.

If you want to improve sound quality, consider frequency response correction and virtualization instead.

On Windows, Equalizer APO and HeSuVi is great freeware for this purpose.

 

[DVDdoug]

Now, I don't really hear a difference as to plugging my headphones into the 2i2 headphone jack.

That's not surprising unless your headphones weren't going loud enough and you needed more voltage. Some headphones are less sensitive than others, requiring more voltage to go as-loud. I don't know how the Scarlett's output compares to the Topping but the Topping probably goes louder.

An amplifier's job is simply to amplify (unless it's got tone controls, etc.). I assume the Scarlett's built-in headphone amp is perfectly adequate.

The output from your PC may be adequate too, unless you're using the Scarlett for something else. If you monitoring while recording, direct monitoring from the Scarlett without going through the PC avoids latency (delay) making it easier to "perform".

 

[AnalogSteph]

TL;DR

1/4" to RCA adapters are a bad idea.

At least the 1/4" TS to RCA (one per channel) variety, which shorts out half the output stage (which may be part of why output impedance is so high on those Scarletts to begin with, the designers wanted to keep things from going wrong too badly if people did plug in a TS). Use a stereo 1/4" TRS to 2x RCA cable to connect to the headphone output instead.

It's definitely a very good idea to add an external "afterburner" in this case, as the Ananda Nano is a very low-impedance (14 ohm) planar - if decently sensitive at 92 dB / mW - and the poor little NJM8065 opamp in the Scarlett is a very unhappy camper above ca. 1 mW into 33 ohms already, so I imagine that would be shifted to less than half a mW here. Muy potato.

Mind you, that's still decently loud in this case (about 88 dB), and the Scarlett's output has some extra headroom that would still cover peaks with adequate fidelity, so if you're not a loud listener in general you may not notice much of a difference. (The low 90s is about the maximum on dynamic classical records for me.)

I would still feel better using the L30 II, which should be capable of something like 3 W - over 126 dB SPL - peak without batting an eye, i.e. you're in hearing damage territory before it gives up. If I have my math right, the Scarlett's headphone out can't clip the amp's input even when using high gain (about 1.4 Vrms out vs. 2 Vrms in).