Metric Halo review

[bordin]

Once I got my ULN-2, I have no more doubt in how high fidelity the MH ULN-2 is. It's changed my perception of audiophile gears. You might be surprised that your $$$$ CD transport and DAC don't produce "perfect" sounds.

 

The combination of OSX, Firewire and MH ULN's offers one of the best sounding systems you could ever find. This integrity must hold.

 

You would be disappointed when you play music through the S/PDIF or AES/EBU input of a ULN, even in the best configuration i.e. the AES/EBU interface card is slaved by the ULN (clock synchronization). Likewise, if you switch from AES/EBU-based audiophile equipments to a ULN-based setup, then you would find the same conclusion about the AES/EBU and S/PDIF.

 

If you already have a Firewire DAC, then you may already have a real audiophile player depending on the internal circuit of the Firewire DAC. IMHO, a ULN-based system is a benchmark for the audiophile community, sound-wise.

 

If you can't afford a ULN-8 or own a collection of standard resolution materials (like me), picking a ULN-2 wouldn't be a wrong decision. You may wait until MH releases its new audiophile versions of the ULNs, but I'm afraid they will sound the same, i.e. the best that MH folks can engineer, as Barry has mentioned.

 

Why wait ? Many people, including me, have searched for the best sounding player. But it seems that we pay a lot of our attention to the deminishing return, isn't it ?

 

Just audition a ULN unit and you would hear something you've never heard before. This may be something you have been finding for a long time. My music collection sounds never before, including Internet Radio (on OSX). Hehe...

 

[ackcheng]

Hello Bordin,

 

So you are saying that firewire connection for ULN is better than AES/EBU? I asked as I plann to use it as a 8 channels converter only!

 

 

 

[bordin]

ackcheng, I mean for 2-channel music playback, Firewire's clearly sounds better than AES/EBU's (using my Lynx AES16e). It was confirmed by my friends who were in the shootouts.

 

I have no experience with its 8 channels converter.

 

[Telstar]

...But I would like to see a DAC only MH unit with a proportionally reduced price and no compromise made on the sound. Maybe allowing DXD. And possibly with windows drivers too.

 

I know that the ULN-8 is a tremendous value in today's market, but it's still 6k$. The DAD is not priced very far from that.

 

[Telstar]

My educated opinion is that 176.4k/192k is the bare minimum NEEDED to appreciate a non "digital" sound.

How much more will be beneficial to our ears? Double that for sure. Possibly 768khz also would bring some improvement to our ears.

 

Not everybody in the industry thinks that 96k or even 192k are enough. Take Chord for instance, they have an interesting writeup on the matter that I have always considered realistic.

 

[Telstar]

Hi Barry,

 

I remember people that liked it on the DAD (which probably has a good enough clock).

Where this added noise come from? From the clock or the software, or PSU maybe...?

 

Back to the DAD, somebody i dont remember compared 192k vs DXD (whcih is pcm at 24/384khz btw) without antialiasing, and especially because of this, found the DXD a big improvement.

I can understand that since i'm sorta alergic to analog filters

 

[bdiament]

Hi Telstar,

 

"Where this added noise come from?"

 

With SACD? It is the noise shaping inherent in the format.

 

Its sounds to me like the dynamic range in the high treble seems to approach 1 dB. (!) In my experience, those parts of the frequency range where a component's (or format's) dynamics are not as wide as they are in others, tend to lend a "character" to the sound.

 

As I said, I know lots of folks who love it. It just isn't for me.

Neither is DXD as a recording/editing/mastering tool, unless and until I hear it outperform the ULN-8. (I'm always ready and willing to listen to anything but will admit I would not bet heavily on the prospect.)

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[Telstar]

No, Barry, I meant between 24/192 and 24/384. Can the latter have more noise, ceteris paribus?

 

Such comparison cannot (because the uln doesnt allow DXD) and shouldnt be done using two different converters. That's why I pointed to the DAD. Not meaning that it is a superior dac to the ULN, at all.

 

[bdiament]

Hi Telstar,

 

"I meant between 24/192 and 24/384. Can the latter have more noise, ceteris paribus?"

 

Oh. I thought you were referring to the rising noise floor of DSD.

 

Ceteris paribus, I don't see why a higher sampling rate would necessarily be noisier. I don't find 192k noisier than 96k or 44.1k. At least not with the MH boxes.

 

But higher sampling rates place greater demands on the clock, along with the other stages (e.g. slew rate in the analog sections, etc.).

 

I've heard many positive reviews of high sample rate devices I find uncomfortable to listen to, so it may be what a given listener hears or wants. (Same with DSD. I find the ULN-8 sounds relaxed and natural and does not engender the stress response I get from even the fine Meitner DSD gear. But some folks I know love the format.)

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

 

 

[ackcheng]

Hi Barry,

 

I wonder how you use your ULN-8? Do you use the firewire interface or do you use it as a AES - analog (DA) converter? A few thread before, someone mentioned that the AES input is not as good as the firewire input. Do you have the same experience?

 

Yours

 

Arthur

 

[bdiament]

Hi Arthur,

 

"I wonder how you use your ULN-8? Do you use the firewire interface or do you use it as a AES - analog (DA) converter? A few thread before, someone mentioned that the AES input is not as good as the firewire input. Do you have the same experience?"

 

I use the Firewire connection between the ULN-8 and my computer. This is the path I take for recording, from the microphone inputs of the '8 and for monitoring during mastering or just listening to music files. (Personally, I feel hard disk playback with good software will beat any optical disk transport at any price)

 

My CD/DVD player is connected to the ULN-8's AES input. This is the only way to get a signal from the player to the ULN-8.

 

In the mention earlier, of the user find Firewire preferrable to the AES input, there is the additional component of the Lynx card (not to mention the AES interconnect). I am sure these will both contribute to a difference, as will (what I believe is) the smaller bandwidth of AES (vs. Firewire).

 

It is also possible (and I have heard talk to this effect) the Firewire implementation in Windows is not as well done as it is in OS X. That user didn't say which OS they are using. If they're using OS X, then we're back to the Lynx itself (plus the added cable).

 

I don't have any issues with using the AES input from my CD/DVD player - especially since I don't know of any player with a Firewire output. ;-}

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[bordin]

Hi Barry,

 

We did A/B tests on the same tracks with Firewire against AES/EBU (from my slaved Lynx AES16e adapter) on the same OSX machine. Just select the audio device in the System Preferences and set the clock source in the MIO Console accordingly. Then, replay the music in iTunes.

 

On Windows, playback sonics using my AES16e has obviously lower quality, mainly compresed and unclear, than in OSX for every comparison.

 

[bdiament]

Hi bordin,

 

"We did A/B tests on the same tracks with Firewire against AES/EBU (from my slaved Lynx AES16e adapter) on the same OSX machine."

 

Understood.

So we (or at least I) still have the question of what the Lynx might be doing. And we have the AES interconnect.

 

Even if the Lynx was perfect, I'm not so sure it is a question of Firewire vs. AES on the ULN or simply Firewire vs. AES (SPDIF).

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[bordin]

Barry,

 

> Even if the Lynx was perfect, I'm not so sure it is a question of

> Firewire vs. AES on the ULN or simply Firewire vs. AES (SPDIF).

 

I bought a Lynx AES16e adapter because it was recommended in the computer audiophile community. The AES16e showed its strength over other AES/EBU interface when using with AES/EBU or S/PDIF DACs. That's what I learned.

 

When my ULN-2 arrived, I was so stunning with its performance, resulting from the Firewire and OSX combo. I believe this is the main benefit of asynchronous nature of the ULN. This can't be done in AES/EBU or SPDIF because the flow control of the AES/EBU standard isn't as rich as in the Firewire standard's.

 

We don't know how ULNs handle the AES/EBU input. It may be reclocked or resampled in order to achieve the lower jitter. IMBO, even there exists such processing inside the ULN, (async) Firewire is superior to the AES/EBU (SPDIF) from my subjective observation.

 

There is still another configuration that may produce better performance, on par with Firewire's. That is to use an external precision ("super") clock, such as Apogee's Big Ben etc, feeding to the master ULN.

 

IMHO, it is uncertain whether this would improve the performance of 2-channel music playback, using AES/EBU or S/PDIF, as it is said in some ads of $$$$$ audio gears. I know pro audio engineers won't believe this.

 

[bdiament]

Hi bordin,

 

"here is still another configuration that may produce better performance, on par with Firewire's. That is to use an external precision ("super") clock, such as Apogee's Big Ben etc, feeding to the master ULN.

 

IMHO, it is uncertain whether this would improve the performance of 2-channel music playback, using AES/EBU or S/PDIF, as it is said in some ads of $$$$$ audio gears. I know pro audio engineers won't believe this."

 

I never tried an external clock with my ULN-2, having great confidence in B.J.'s design (for those who don't know, B.J. Buchalter is the designer of the Metric Halo and Sonic interfaces). The ULN-2 clock was made even better with the 2D mod MH released a while ago.

 

I can say that the clocking in the ULN-8, like every other aspect of the '8, has not been beaten. Adding a Big Ben takes the performance down not up. (I would not be surprised if this turned out to be the case with the ULN-2 also.)

 

Regarding your experience with Firewire vs. AES, my belief is this is due to inherent differences between the formats and not because the ULN-2's AES is somehow "not as good". In other words, it isn't the ULN-2's AES, it is AES itself, when compared with Firewire. That's my take on it anyway.

 

It is wonderful to read of your experiences with the ULN-2. After I first heard Metric Halo's hardware (and software), I quickly became a fan as well as a customer (and shortly thereafter, a beta tester). I am still amazed at how much sonic goodness there is in that little box, not just as a DAC but for the many other wonderful capabilities it has.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[labjr]

I was thinking that someone would make AES/EBU or S/PDIF sound as good as asynchronous interfaces at some point and the sound would be the same regardless of the input. But what's the point really. S/PDIF or AES/EBU is inherently flawed. It just takes too much work to fix it. So why not just have one good interface?

 

Regards,

 

Larry

 

[bdiament]

Hi Larry,

 

"So why not just have one good interface?"

 

We already do. ;-}

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[labjr]

Hi Barry,

 

I guess maybe my point wasn't clear.

 

I don't see the point of needing every kind of input that exists to have a good product. AES/ EBU S/PDIF is always going to be flawed. Yeah there's probably a way to reclock it somehow and make it sound great, but it would be a huge effort so why not get rid of it and have just one interface like Firewire or USB. It's easier to make it work well and it helps keep the cost down. Charlie Hansen and Gordon Rankin have made similar statements before when criticized for not having multiple inputs on their DACs.

 

Regards,

 

Larry

 

[bordin]

Hi Larry,

 

I've pursued the same wish you mentioned above, but fortunately it turned out to be a happy ending, getting a ULN-2 !! After having direct observations and listening to engineer friends, it is impossible to make AES/EBU or S/PDIF to sound as good as what asynchronous Firewire (and USB) offers.

 

It could be 90+% approaching but never 100% equal performance, period IMBO. We've talked about this in New Dichotomy - Async vs. Non-async DACs

 

Some of my friends said to me "You distinguish 90+% from 100% sonic reproduction with 100+% biased mind of your musical preferences !!".

 

Regarding multiple inputs, it is in fact what the customers choose, not the designers or sale reps. :-) Flexibility v.s. Accuracy. ;-)

 

[bordin]

Hi guys,

 

I just had a chance to test my ULN-2's Analog outs connecting directly to my power amp. The Analog outs can be variable using the master volume control in the MIO Console's Mixer. This digital volume-control output stage has *higher* gain than other preamps, but surprisingly, the noise floor is *very* low. Thanks to MH's engineering "recipe".

 

So, a ULN can be used as a preamplifier . The performance is top-notched, IMHO !!

 

If you have a ULN, then you may try this. Don't forget to turn the master volume down first. Simply move the mouse pointer over the Master Volume and roll the mouse wheel.

 

[cfmsp]

 

"This digital volume-control output stage has *higher* gain than other preamps, but surprisingly, the noise floor is *very* low. Thanks to MH's engineering "recipe"."

 

I've been listening exclusively to my ULN-2 directly to my J2 all week. I agree that the quality of the MIO volume control is excellent, in spite of BJ's quite characteristic humility as displayed in his response to Barrows re use of volume control in MIO versus preamp.

 

I can agree with Barrows that for near perfect preamps - those that sound 'better' than a straight wire with gain - it might make sense to run the signal though a preamp and another pair of interconnects, but for pure value, I'm very happy with the ULN-2 in 'hot-rod' mode. I can double the price I spend on interconnects between the two.

 

Re your comment "This digital volume-control output stage has *higher* gain than other preamps" - what setting are you using in the "+4/-10" (pro/consumer) button on the rear?

 

clay

 

 

[Audio_ELF]

Larry commented... "I don't see the point of needing every kind of input that exists to have a good product. AES/ EBU S/PDIF is always going to be flawed. Yeah there's probably a way to reclock it somehow and make it sound great, but it would be a huge effort so why not get rid of it and have just one interface like Firewire or USB. It's easier to make it work well and it helps keep the cost down. Charlie Hansen and Gordon Rankin have made similar statements before when criticized for not having multiple inputs on their DACs."

I think one reason is that these days a lot of people (even audiophiles) have multiple sources. Apart from their computer, a lot of people will possibly have (even in a 2-channel system) a digital radio, a DVD player, a iPod dock, possibly a devices such as Apple TV or a Squeezebox or Airport Express. If you have a single input DAC, then only your computer can benefit from the DAC, but if you can connect all of them, then all have the better digital decoding. So yes, making a "one input" device may keep costs down, but if you want to enhance a number of devices, then if you have multi-inputs the costs are spread.

 

Personally I find devices such as the Ayon Skylla exciting as it offers the potential for a single box to combine DAC and high quality pre-amp. Whether it's any good is another question, but the potential is there.

 

Eloise

 

[cfmsp]

 

 

"So yes, making a "one input" device may keep costs down, but if you want to enhance a number of devices, then if you have multi-inputs the costs are spread."

 

Totally agreed, Eloise, as usual.

 

I'd also like to point out that for/at the highest quality levels, DACs that can feed power amps directly have an advantage (this is a strength of the Alpha). Given that, DACs that have multiple inputs become even more useful - for the reason you mentioned.

 

I'll go further and say that in my opinion the pro audio DACs (with ADCs and built-in preamps) become even more interesting to an open-minded audiophile. :0

 

clay

 

 

 

 

[bordin]

Hi Clay,

 

>what setting are you using in the "+4/-10" (pro/consumer) button on the rear?

 

It's +4 dB configuration so that the gain is high.

 

[ciamara]

I assume that if you are using +4dB on the outputs, you are sending the signal to an amplifier/receiving piece of gear designed to accept this level of gain. If you were to run +4dB into consumer RCA inputs (which expect signals in and around -10dB), you run the risk of overdriving the gain stage, which could in some cases cause distortion. Just checking ...