[ThanatosVI]

I don't know of any crossfeed stand alone implementation.
The only implementation I know personally is the Meier Audio Corda Classic, which I don't use anymore but got lying around.

If searching for an endgame solution I'd probably go for an T+A Ha200 or dCS Bartok, they both got this "in their kit", I'm pretty sure there are some challenges as stand alone device, which are hard to overcome, therefore nobody cared to create such a niche product.

 

[Edric Li]

Some known commercial passive crossfeed:

1. Jensen Space Perspective CFN-I (1963)
Info: https://worldradiohistory.com/hd2/I...o-IDX/IDX/60s/Audio-1963-03-OCR-Page-0057.pdf
Ebay: https://www.ebay.com/itm/Vintage-CF...516395?hash=item23d57bcf6b:g:d4wAAOSw6nNemWBd

2. Meier Corda Cross-1 (2003)
Info: http://web.archive.org/web/20060425144205/http://www.meier-audio.homepage.t-online.de/cross.pdf

3. Xin Feng XinFeed (2003)
Info: http://web.archive.org/web/20030626153051/http://www.fixup.net/products/pktamp/xinaddon.htm

Headphones that put a secondary driver in each ear to reproduce the opposite channel:
1. Toshiba HR50 (1973)
2. Lear NSS-U1 (2015)
3. Crosszone CZ-1, CZ-10 (2017)

 

[piglet]

On the subject of crossfeed I'd like to mention the Meridian Audio Prime headphone amplifier which I use myself. This has crossfeed and I find this to be a very good implementation. Meridian have given it the rather grand name of "Analogue Spatial Processing" and there are two levels. It coheres the soundstage and seems to have little negative impact.

Some 60s recordings are extremely difficult to listen to without crossfeed because they put all of some instruments into each channel. One example of many is the album It's All Right by the Wynton Kelly Trio which I've just started listening to now, actually, as I am writing this. Without crossfeed it is unlistenable, then I press the button on the Meridian Prime and now it sounds beautiful, everything just shifts into place.

So, I do believe that crossfeed is an essential thing to have and yet so many headphone systems don't have it at all.

 

[Waddiewadkins]

iFi, et. al,


You should:
(a) Try to market/sell your x-feed as a STAND-ALONE product.
(b) Call it "crossfeed". Or "analog crossfeed". Don't call it call it "3D". This is confusing. I'm not too sure who iFi's prmary market is. However, most headphone enthusiasts know what x-feed (crossfeed), highly respect it for that, is and often buy products based on that familiarity. "3D" is confusing terminology -- it sounds like some sort of digital holographic simulator (like Hughes SRS, or other FAILED and long-abandoned concepts). Analog crossfeed is REAL, effective, TRUSTED and has been used for many decades in myriad headphone amps ... and the well-established terminology is very familiar to audiophiles.

I'm a lowly dongle dac/amp researcher led here because ifi have this fantastic function in their affordable portable dongle range. Specifically ifi go blu.. Now, when this is being compared to competitors Quedelix and Btr7, they fail to mention that the ifi has this fantastic analog feature that completely changes the soundstage of the headphone quality, and in a good way. Without it, you are just not going to mould mono panned jazz recordings from the 50s and 60s into a fundamentally different staging at all. So I'm trying to clear that up right now and I've found myself here.

 

[ExTubeGamer]

I do have to say that i like the software implementation of crossfeed in the linux software "easyeffects". if you know how to set it up it can be quite useful in cleaning up recordings made for speakers. To my ears it sounds like the stage is getting an inch smaller while low freq rumble gets toned down.

 

[Waddiewadkins]

I do have to say that i like the software implementation of crossfeed in the linux software "easyeffects". if you know how to set it up it can be quite useful in cleaning up recordings made for speakers. To my ears it sounds like the stage is getting an inch smaller while low freq rumble gets toned down.

Come across something called canopener, seems to be highly lauded..but I'm 10 years too late they don't offer it as a mobile app any more..have been looking at a thread from 2014 and they are all blown away by it.. kind of frustrating,, busy a company called goodhertz,, they still are flying for studio computer plugins but they gave up on iPhone ios app platform. You can get it for your desktop. Not sure about tablets..Didn't get enough support from Apple store or something... check it out.. Will that Linux thing work on my phone, I'm showing my cluelessness probably with that question

 

[ExTubeGamer]

Come across something called canopener, seems to be highly lauded..but I'm 10 years too late they don't offer it as a mobile app any more..have been looking at a thread from 2014 and they are all blown away by it.. kind of frustrating,, busy a company called goodhertz,, they still are flying for studio computer plugins but they gave up on iPhone ios app platform. You can get it for your desktop. Not sure about tablets..Didn't get enough support from Apple store or something... check it out.. Will that Linux thing work on my phone, I'm showing my cluelessness probably with that question

It will never work on your phone.

If you like using crossfeed on your phone I can recommend the neutron player. The built in crossfeed sounds good and you can set db and frequency. Available as demo version and for a small fee as full version. Best audio solution on Android imo.

 

[Thorsten Loesch]

ifi has this fantastic analog feature that completely changes the soundstage of the headphone quality, and in a good way.

Just a warning, non of the other current "Crossfeed" systems (minus SPL Phonitor AFAIK and what I designed for iFi) is based on the actual required generalised HRTF, causing them to function acoustically incorrectly.

They are all based on the transfer function from a single source, which was not measured and instead created at "green table" based on some theoretical assumptions (Bauer Crossfeed). Every single crossfeed since has tried to work based on this target (and lists it in references if honest). It looks like this:

Such crossfeed actually does not "work" correctly. They kinda work, with some recordings, but the target is wrong so it only works with recordings that also sound wrong on speakers.

What is actually required is shown above, crossfeed needs to replicate approximately the difference between L/R ear, to emulate a speaker placement of around 60 degrees ("standard speakers"). You can see the right signal is still present at left ear with about constant attenuation od ~ 8dB above ~ 1.5khz and no more than 12dB attenuation at 10kHz, while below 200Hz the difference is minimal.

Most of software are also based on the same reference as the hardware solutions and as a result have the same issues. You need something like Waves NX to get something based realistic targets.

And of course, whenever the people who think they "know" what crossfeed is like from all the wrong examples, they will state that this is not crossfeed, because it is not the same as all the other wrong cross feeds.

And most people do not like crossfeed and claim "it's only good for certain recordings" and "doesn't sound right with most recordings" and all that shapes both opinion and expectation.

Further, due to the limitations of most recordings, even a "correct" crossfeed will present a rather narrow soundstage, if forward from the head. In terms of perspective a midhall perspective recording would be presented more like listening from the boxes in the rear. So additional correction is required to move both listener and soundstage "forward" and give a more realistic soundstage width.

Thor

 

[ExTubeGamer]

I simply see it like this: Bauer Crossfeed is a useful tool to manipulate the soundstage of your headphone. Sometimes I use it to make the soundstage more focused. I enjoy using it on IEMs to manipulate the frequency response and stop audio from being too left or right panned.

 

[alphaman]

There seems to be a gazillion crossfeed implementations. Both hardware and software (digital domain). I'm only interested in the hardware. Not unless, say, a major player like TI or AD creates a dedicated chip (ASIC) for xfeed.
All that said, and of the ones I've heard, I think Tyll's Headroom ckt was the best sounding: The fidelity actually improved in addition to xfeed imaging HRTF benefits. In others' designs, like Meier and Modified Linkwitz Crossfeed [https://tangentsoft.com/audio/mlxfeed.html], fidelity always suffers with xfeed switched in.

 

[Edric Li]

Off-topic, but it is kinda nuts that neither the Sony DMP-Z1, Ibasso DX320MAX nor the Lotoo Mjolnir has crossfeed. None of the new Cayin, Mass Kobo or Brise Audio amps has it either. The high-end portable market is still void of a product with crossfeed since Hugo 2.

 

[Waddiewadkins]

It will never work on your phone.

If you like using crossfeed on your phone I can recommend the neutron player. The built in crossfeed sounds good and you can set db and frequency. Available as demo version and for a small fee as full version. Best audio solution on Android imo.

Thank you sir

 

[ExTubeGamer]

There seems to be a gazillion crossfeed implementations. Both hardware and software (digital domain). I'm only interested in the hardware. Not unless, say, a major player like TI or AD creates a dedicated chip (ASIC) for xfeed.
All that said, and of the ones I've heard, I think Tyll's Headroom ckt was the best sounding: The fidelity actually improved in addition to xfeed imaging HRTF benefits. In others' designs, like Meier and Modified Linkwitz Crossfeed [https://tangentsoft.com/audio/mlxfeed.html], fidelity always suffers with xfeed switched in.

Have you tried a Meier Audio amp already?

 

[Thorsten Loesch]

I simply see it like this: Bauer Crossfeed is a useful tool to manipulate the soundstage of your headphone.

Well, it doesn't create the correct transfer funtion required, so it is either an effect or band aid that doesn't work correctly.

There seems to be a gazillion crossfeed implementations.

Yes, but they mostly implement the incorrect acoustic behavior based on an early 1960's publication by Mr Bauer.

Both hardware and software (digital domain). I'm only interested in the hardware. Not unless, say, a major player like TI or AD creates a dedicated chip (ASIC) for xfeed.

Considering how few parts it takes, it just needs to be implemented. Here a slightly unusual implementation of Bauer Crossfeed. That is of course the one that doesn't work correctly, but it illustrates the relative simplicity:

All that said, and of the ones I've heard, I think Tyll's Headroom ckt was the best sounding: The fidelity actually improved in addition to xfeed imaging HRTF benefits.

That was a fairly complex circuit. It was a little different from generic Bauer Crossfeed but suffers similar problems (excessive HF Chanel Separation). More here:

https://www.stereophile.com/headphones/530/index.html

I the full circuit at hand, I have my doubt that in an absolute sense it improved FIDELITY (as opposed to perceived sound quality), compared to a bypass.

In others' designs, like Meier and Modified Linkwitz Crossfeed [https://tangentsoft.com/audio/mlxfeed.html], fidelity always suffers with xfeed switched in.

For a Crossfeed circuit, there should be no change to frequency response with a mono signal.

A stereo signal "hard panned" should not see the active Channel altered, only the inactive channel should have "signal leakage", like it would be with a real signal from a speaker.

Not many Crossfeed implentations comply. They are based on Bauer, which is inaccurate.

Even if adjustable for all parameters, like many DSP versions are, the fundamental problems remain.

Thor

 

[Waddiewadkins]

It will never work on your phone.

If you like using crossfeed on your phone I can recommend the neutron player. The built in crossfeed sounds good and you can set db and frequency. Available as demo version and for a small fee as full version. Best audio solution on Android imo.

Just bought Neutron. I've clicked the crossfeed presets on but not getting any results as yet. I'll have to.work on it.