Help re different methods of driving and EQ-ing headphones?

[ADUHF]

The combo jacks are normally used on audio interfaces so you can run 1/4 inch TRS plugs at line level or XLR microphone cables for mic level.

I am not sure what the use case is on a headamp.

They just offer different connection options for +4 dBu line-level balanced inputs, so you don't have to use 1/4" TRS to XLR cables or adapters if you're coming from a balanced source that only has 1/4" TRS outputs (like on the Mackie Mix8, for example). It just makes the cabling a little easier.

Anyway, I hope you will be happy with the Rolls unit.

Me too. And thank you for the well wishes.

If not though, then I'll just send it back, and maybe try somethin else.

 

[ADUHF]

And I meant to say you got a nice choice in the dbx eq unit. They make great stuff.

They are not strictly speaking "audiophile grade". But I have used DBX graphic EQs in my headphone audio chains before. And they work ok. They are a little cumbersome though, and seem to play a little nicer with +4 dBu balanced pro audio. So I'd probably still want to keep a mixer (or some other type of line-level converter) in the pipeline to provide them a decent signal. And I'm not sure I'll really need that level of precision for most of my uses with this setup.

I think the 3-band EQ controls on the mixers will be fine for most stuff with the DT-770 and M50x. As others have pointed out, these are both fairly easy headphones to EQ (though the FR on the M50x is a bit rougher than the DT-770). And if I need a bit more precision for listening to YouTube videos or music off the web (which is where I get most of my music now), I can always add a digital EQ on my computer for that.

 

[gimmeheadroom]

They are not strictly speaking "audiophile grade". But I have used DBX graphic EQs in my headphone audio chains before. And they work ok. They are a little cumbersome though, and seem to play a little nicer with +4 dBu balanced pro audio. So I'd probably still have to keep a mixer (or some other type of line-level converter) in the pipeline to provide them a decent signal. And I'm not sure I'll really need that level of precision for most of my uses with this setup.

I think the 3-band EQ controls on the mixers will be fine for most stuff with the DT-770 and M50x. As others have pointed out, these are both fairly easy headphones to EQ (though the FR on the M50x is a bit rougher than the DT-770). And if I need a bit more precision for listening to YouTube videos or music off the web (which is where I get most of my music now), I can always add a digital EQ on my computer for that.

I really like parametric EQ and I don't use graphic EQ. But dbx is good stuff. They used to have some audiophile gear but I think they're completely into pro gear and have little consumer market nowadays.

 

[gimmeheadroom]

They just offer different connection options for +4 dBu line-level balanced inputs, so you don't have to use 1/4" TRS to XLR cables or adapters if you're coming from a balanced source that only has 1/4" TRS outputs (like on the Mackie Mix8, for example). It just makes the cabling a little easier.

Well I find it confusing since most of the time the combos are for different signal levels. What you said makese sense but I can also imagine sombody blowing up it or some other piece of gear when they get confused.

 

[ADUHF]

Well I find it confusing since most of the time the combos are for different signal levels. What you said makese sense but I can also imagine sombody blowing up it or some other piece of gear when they get confused.

I am not an expert in pro audio. So take most of what I say on the subject with a grain of salt.

I've done a fair amount of "dabbling" in the medium though. And a good rule of thumb that I learned fairly early on is don't stick anything into anything else if you don't know what it is. Because bad things can potentially happen. There is a reason it's called "pro". And it does require a little knowledge and training to understand and use well.

Another rule of thumb I like to follow is don't adapt, unless it's absolutely necessary. This applies mainly to cabling. I don't really like going from RCA to 1/4", or 1/4" to XLR, for example, unless there's no other option. Because the specs on the cables are different. And sometimes the results can be unpredictable.

If you're going balanced to balanced. Or unbalanced to unbalanced. Then it may be ok... sometimes. But I still try to avoid it, whenever possible.

A third good rule of thumb is never assume. Like never assume that because one thing has a connector that looks like another thing that it's ok to connect the two together. If you don't know what you're connecting, then it's probably better not to connect them.

 

[ADUHF]

I got a call back today from a Yamaha tech about the impedance rating on their AVRs. And have removed the impedance and damping factors on those from the previous chart for now.

The 470 ohm "output impedance" on the Yamaha AVRs' headphone amp appears to be the load impedance, rather than the source impedance. So based on the spec, they output 470 millivolts (which is different than milliwatts) with a 470 ohm load or headphone.

https://usa.yamaha.com/files/download/other_assets/2/794512/web_ZU46020_R-S202_om_UA_En.pdf

The tech had no further info on the actual source impedance of the headamps on the AVRs. Maybe there's some way to calculate that, and also the power in milliwatts, from the above info though. The 470 millivolt rating above is for a 1 kHz signal on the CD input btw.

 

[ADUHF]

Listening to some Sade, Little Big Town, Madilyn, etc. on my used 250 ohm DT-770's with my new Bellari HA543 headamp. Super clear, super flat sound! Wow!

https://www.head-fi.org/threads/youtube-music-clips-for-testing-audio-gear.939698/

I don't really have a good basis for comparison, but this sounds just crazy good for $99. I've bypassed the mixers and EQs for the moment, and just went straight from the Insignia DAC into the amp via RCAs to see how the unit sounds by itself. And so far, it sounds just great without any EQ! Also tried the "Enhance" button, and it does indeed seem to dial down the mids, and dial up the ends, adding a Fletcher-Munson effect. It is overkill imo for the 250 ohm DT-770's though, which already have excellent extension in both the bass and treble. And don't really need any more emphasis in those areas. The 250-ohm DT-770 also has luscious mids, and you definitely want to hear that,... along with the excellent bass and treble.

This HA543 is quite compact btw, and takes up very little space for a desktop amp. It's about 4.5" wide, 2.75" deep, and a little over 1.5" tall. Not super heavy. But heavy enough to stay put, as long as you don't yank on the headphone cable too much. The rubber non-skid feet also help with that. Connectors are all gold-plated. Blue LED power light. Matte black metal case. Lovingly built in Utah, by Rolls-Bellari elves I assume. (Hence, the small size.)

Total expense for all the above was $263 + tax. ($139 for the HPs. $99 for the amp. $20 for the DAC with a $10 BB cert. applied, and $5 for the optical cable). Not too shabby.

I should perhaps mention again that one of the reasons I chose this particular model is because it has the balanced XLR inputs, as well as the usual RCAs. I wanted that for broader compatibility with both consumer and pro audio gear. Other factors that weighed in the decision were the comparatively low price. And the familiarity I have with this brand. (I'm glad to support some Utah elves as well, when it's possible.)

 

[ADUHF]

Tried the XLR inputs on the Bellari HA543, using the balanced outputs on a couple of my mixers. And they also seem to work fine. I had a couple minor issues getting the power connector properly attached. That seems to be one of the cheaper and less impressive parts of the amp. But aside from that, it has pretty much been smooth sailing so far. And seems to have a pretty good sound for the price.

I wish the elves had made it maybe a little bit bigger and heavier. But the size and weight haven't been a major issue so far, especially after cables are connected. And I could always try putting it inside a somewhat larger heavier case, if need be.

 

[ADUHF]

Finally decided to give a digital EQ a try with my setup. Wish I'd done this sooner.

At the moment, I'm just using a very basic 10-band graphic EQ that works as an extension in my browser with YouTube. It doesn't seem to work with the video clips posted on Head-Fi though. Just on YouTube, so far. Not sure why. But in the description, it says the extension does not work with sites that use Flash or Silverlight. So maybe that's the issue.

There are other EQ extensions I can use with parametric controls as well. But I'm tryin to keep things simple right now. And just glad to have some ability to tweak the bass and treble again, when watching videos on YouTube. I had sort of gotten used to the sound of my Beyer DT-770's without an EQ. But I missed that capability. And I think the bright treble on these HPs was probably fatiguing my ears too much.

Still usin the little Rolls-Bellari HA543 as my amp. And so far, it seems to be workin just fine (knock wood). I keep it on the floor now though, because it kept falling off my desk.