Headphones preamp recommendation

[Shandar]

I'm an hobbyist electronic music producer and I've just bought a pair of Sennheiser HD 700. I will use them as my monitors since I don't have the space/money to properly setup a room just to make music.
Now I need to connect them to my pc. I asked Thomann customer service about suggestions in the 300 euros price range, and they proposed these
* https://www.thomann.de/gb/korg_ds_dac_100.htm
* https://www.thomann.de/gb/fostex_hp_a4.htm

Ideally I don't want to colour the audio. Do you have any experience / advice?

[Mister Natural]

this would be more more versatile for you than the two mentioned above : https://www.thomann.de/gb/tascam_us_2x2.htm

best of luck

[Shandar]

Well, I didn't considered an audio interface... interesting suggestion.
I'm not sure about it though, because
1) I don't have any hardware, except a midi keyboard, and I'm not planning to buy any
2) I think the output impedance is too low for the headphones: the latter have an impedance of 150 ohm, while the former is 32 (maybe) -> http://tascam.com/product/us-2x2/specifications/

Maximum output level
18mW+18mW or more
(THD+N 0.1% or less, 32ohms loaded)

[Shandar]

Reading the Korg DAC specifications I learned that I don't know anything about how impedance works

Load Impedance: More than 16Ω
Maximum Level: 85mW + 85mW @32Ω

[stratum]

If this was a valve amplifier you would care about impedance matching.
For solid state amplifiers one doesn't need to care to about impedance matching (especially if it is driving an headphone), other than the fact that the load just needs to have a higher or equal impedance to the one specified. The info you have posted also mentions this very briefly.
If the amplifier was driving a speaker instead of an headphone, a matched speaker gives you more power, but that's just it.
This is in contrast to the valve amplifiers for which an unmatched load can be dangerous in either way (high or low).

[Shandar]

Thanks for the clarification.
I'm starting to think if I need an amplifier at all, or it should suffice to connect the headphones directly to the notebook phones output?

[Shandar]

I ended up buying the Steinberg UR22 MKII.
I hope I'll be able to make it work with Bitwig without issues.

Thank you all for your help.

[Shandar]

I just tried the steinberg interface and I think I made a mistake buying it.
The output volume is more than enough, but there's no body in the sound: a solid drum loop turn almost into crackles.
It's not an asio issue, since I rendered the loop and I listened to the same audio file once with the interface, and once connecting directly the headphones to the audio output of the pc.
I already updated the drivers and the firmware with no avail. I'm powering it via usb.
Any suggestion before I send it back?

[t3toooo]

Reading about the UR22 MKII seems that using higher ohm headphones only suffer from lower volume but no crackles.Maybe it is defective?
The output should be the same or better than the PC on board output.
Does this happen with Youtube or soundcloud as well?

[Shandar]

I listened to a song on Soundcloud and I noticed the same behaviour: the sound was less full, as there were less low frequencies.
Since the low frequencies seem to be lost, the percussion transients are more prominent and that's why I compared them to crackles.
As i stated the max volume is enough to hurt my ears, so that's not the problem.

I'm not an expert, but knowing that low frequencies require more energy, couldn't it be a power issue? Maybe I should power the interface with the micro usb...
To be honest I don't want to buy another cable just to discover that that wasn't the issue.

[t3toooo]

You can try two things.
Find a cheap headphone,borrow it from a neighbor,best are those cheap bass-boomy ones because you can be sure that they have low impedance. InEar works as well.
If it is the same,the interface could be defective.

You can borrow a micro-USB cable from a neighbor,everybody has this kind of cable.

Did you turn the mix input knob to "DAW"?

[lfm]

I just tried the steinberg interface and I think I made a mistake buying it.
The output volume is more than enough, but there's no body in the sound: a solid drum loop turn almost into crackles.
It's not an asio issue, since I rendered the loop and I listened to the same audio file once with the interface, and once connecting directly the headphones to the audio output of the pc.
I already updated the drivers and the firmware with no avail. I'm powering it via usb.
Any suggestion before I send it back?

I had the same experience with Beier Dynamics, or what they are called.
It's about also being able to drive high end enough.

Later bought HD 650 though, and this preamp to go with it:
http://box-designs.com/main.php?prod=he ... er&lang=en

Setting output to -10dBV gets it ok.

Works fine for up to 300 ohm I think. 600 ohm might not be loud enough.
Then you get what phones deserve.

I usually run with knob on 1300-1400 hours and good volume. So can max out for shorter period.

Don't expect any standard headphones out to do the job. They put no money on that. Cheapest possible.

Possibly a Mackie mixer, which is really, really loud at least, but have not tested HD650 on them. Just do HD280 on that, and not for mixing.

[Shandar]

You can try two things.
Find a cheap headphone,borrow it from a neighbor,best are those cheap bass-boomy ones because you can be sure that they have low impedance. InEar works as well.
If it is the same,the interface could be defective.

You can borrow a micro-USB cable from a neighbor,everybody has this kind of cable.

Did you turn the mix input knob to "DAW"?

You're right: I was in panic mode and I didn't thought about changing the gear involved.

I tried all combinations with my 3 different computers:

1. My current pc, a custom built notebook made by Schenken with Windows 10
2. My old pc, a Dell notebook with Ubuntu
3. My wife's Mac Pro

my 2 headphones:

1. Current: Sennheiser HD700, 150 ohm
2. Old: Sennheiser HD595, 50 ohm

2 different output:

1. Direct from the headphone pc output
2. Steinberg interface powered by usb (I also tried to power it via micro usb but nothing changed)

The result left me surprised: everything sounded like the steinberg interface connected to my current pc, except the headphone output of my current pc, which sounded fuller and "better".

So my initial assumption was wrong: it's not the Steinberg interface lacking in the low frequencies, it's the audio card of my pc exagerating them.

Furthermore I noticed that also the mid frequencies are attenuated in the headphones output, so the standard consumer can benefit from a sound fuller and less mudded.

I immediately searched for some setting in the audio (windows 10) and the sound card, but nothing seemed to be activated. So I have to infer that this frequency response is something embedded in the sound card headphone output.

I'm definitely angry because everything I made in the last three years, since I changed pc, sounds wrong. Now I understand why my music mastering sounded always amateurish on my pc at work compared to what I usually listen to on spotify.
To be honest, having payed my current pc more than 2k euros, I didn't expect a behaviour like this. I will write to Schenken to find out more about it.

And yes, the output level of the interface could be a bit higher. Listening to some music on youtube or souncloud the level is more than enough, but the volume level in many synth presets is low and now I need to raise the volume of the track to get a decent level.
I used to mix at a lower level, and only in the mastering phase I raised the overall level. Now I need to get near the 0db peak from the start.
Switching headphones between 150 ohm (HD700) and 50 ohm (HD595) doesn't affect the volume perceived.

At the moment I'm thinking that I don't need an audio interface and a dedicated DAC like the Korg one would have been better because

1. More room to raise the volume level
2. My Panorama P6 is connected to my pc by usb, so I don't need any MIDI input

Furthermore I don't notice any difference in the audio between the headphones output and the Steinberg interface in my old pc or my wife's Mac, so I'm still wondering if I need an audio interface / headphone preamp at all.

But now I need to experiment some more to get used to the new setup and I hope I'll change my mind.

[mod slayer]

What are you talking about? There's more power in UR22 than is needed to blow your head off. Check your system volume.

[Shandar]

What are you talking about? There's more power in UR22 than is needed to blow your head off. Check your system volume.

I triple checked all knobs of the interface (yes, the input/daw knob is turned completely to daw) and all volume settings inside windows 10.
I experimented with WASAPI, FL Studio ASIO and Steinberg (Yamaha) ASIO interfaces inside Cubase 9.5 and Bitwig.

With the headphones direct output of the sound card I used to set the volume to 60% and in Bitwig the track fader at -10db.
With the interface I have to set the volume at 100% and the fader at -5db to get a similar result.

Furthermore I found out that with ASIO there's no software volume control.