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Meridian Explorer DAC/Amp Stream of Consciousness Review (WARNING: Not Good) - Page 3

post #31 of 105
2/26/13 at 12:20pm

Wow, no wonder you totally screwed up the FR. I'm not sure if even 300Ω would be safe from that thing.

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post #32 of 105
2/26/13 at 12:23pm
Thread Starter 
Quote:
Originally Posted by Tyll Hertsens View Post

Wow.

 

You sure you were measuring the headphone jack?  tongue_smile.gif

 

I'll have one soon to confirm, but that's a spectacular error.

 

Yeah, I used the jack with the headphone symbol. The other jack has an input symbol and a red light thing-a-ma-jig (optical doodad.)

 

I still can't but feel that I screwed up somewhere. It was the reason I took output Z measurements from two other devices - as a control to make sure my measurement methodology was not erroneous. I've made measurement mistakes before, so its up to you guys to keep me honest and provide peer review.


Edited by purrin - 2/26/13 at 12:25pm
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post #33 of 105
2/26/13 at 12:25pm
Quote:
Originally Posted by purrin View Post

 

OUTPUT IMPEDANCE

 

Objective2 amp: 1.46 ohms

UHA-6HS: 0.95 ohms

Meridian Explorer: 47.95 ohms

 

 

Are you yanking our chain!?! LOL!

47.95?!!?!?

 

Quick question, have you ever seen something like that coming from an amp?!?! I think the highest I saw was from a NuForce amp and it even reached 15 or so (if I'm not mistaken...)

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post #34 of 105
2/26/13 at 12:28pm
Quote:
Originally Posted by purrin View Post

 

OUTPUT IMPEDANCE

 

Objective2 amp: 1.46 ohms

UHA-6HS: 0.95 ohms

Meridian Explorer: 47.95 ohms

 

 

Holey buckets. Assuming this measurement is reasonably accurate, then it would behoove Meridian to disclose it, or at least allude to the potential performance impact. I would not be pleased if I sourced this as a sole driver of headgear that is adversely affected by high output impedance. It's one thing to make a product decision that cuts away a portion of the market; it's another thing to make them find out the hard way.

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post #35 of 105
2/26/13 at 12:30pm
Thread Starter 
Quote:
Originally Posted by gelocks View Post

 

Are you yanking our chain!?! LOL!

47.95?!!?!?

 

Quick question, have you ever seen something like that coming from an amp?!?! I think the highest I saw was from a NuForce amp and it even reached 15 or so (if I'm not mistaken...)

 

This is why I asked if anyone has seen published specs from Meridian on this.

 

As to your question: Only from tube amps with switches between low and high output Z. And even then, nothing that high! (The Schiit Lyr output Z is 25ohms, but Schiit does warn you not to use it with certain headphones.) High output Z comes in handy with HD800s, which some people do understandably prefer.

 

 

Quote:
Originally Posted by Aerocraft67 View Post

Holey buckets. Assuming this measurement is reasonably accurate, then it would behoove Meridian to disclose it, or at least allude to the potential performance impact. I would not be pleased if I sourced this as a sole driver of headgear that is adversely affected by high output impedance. It's one thing to make a product decision that cuts away a portion of the market; it's another thing to make them find out the hard way.

 

Given, the HF hype train, and the way Meridian seems to have handed off samples to various publications with a wink-wink, I gather Meridian will have no issues selling a ton of these. Besides, the extremely high output Z does provide a pleasant, forgiving, musical, organic sound which many people like. I wouldn't consider it high-fidelity sound though. I was actually serious when I said my VAIO out (which is actually not bad) sounded better than the Meridian.


Edited by purrin - 2/26/13 at 12:35pm
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post #36 of 105
2/26/13 at 12:32pm
Has it occurred to anyone that perhaps purrin just has a faulty unit?

Listening to Abbey Road just singing here on mine.
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post #37 of 105
2/26/13 at 12:37pm
Thread Starter 
Quote:
Originally Posted by netdog View Post

Has it occurred to anyone that perhaps purrin just has a faulty unit?

 

It's possible. I tend to be a magnet for defective gear. Or at least gear which does not pass QA. About 90% of stuff I don't like or measures badly happens to be defective.


Edited by purrin - 2/26/13 at 12:41pm
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post #38 of 105
2/26/13 at 1:17pm
Quote:
Originally Posted by gelocks View Post

 

Are you yanking our chain!?! LOL!

47.95?!!?!?

 

Quick question, have you ever seen something like that coming from an amp?!?! I think the highest I saw was from a NuForce amp and it even reached 15 or so (if I'm not mistaken...)

 

~$30 Behringer UCA202.
 

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post #39 of 105
2/26/13 at 1:51pm
Quote:
Originally Posted by purrin View Post

 

 

Meridian seems to have handed off samples to various publications with a wink-wink

 

Besides, the extremely high output Z does provide a pleasant, forgiving, musical, organic sound which many people like. I wouldn't consider it high-fidelity sound though. I was actually serious when I said my VAIO out (which is actually not bad) sounded better than the Meridian.

 

What do you mean by handed off with a "wink-wink?" Sounds so nefarious.

 

Clearly high output Z is an issue (apparently), but the Explorer may be very high fidelity indeed when not driving headphones that are adversely affected by high output Z, not to mention when used only as a DAC. Not that Meridian shouldn't be forthright about its performance and design choices regarding the amp section, or that we shouldn't hold the amp performance into account. But there is listening beyond IEMs, and many IEMers probably have picked suitable amps accordingly, and may still benefit from the Explorers DAC. I do use the amp, but found DAC-only reviews most compelling, and also plan add an outboard amp myself. 

 

But dang, 50Ω. If we accept 1/8th of headphone impedance as a guideline for when output impedance becomes an issue, that even brings 300Ω headphones into question. Like my HD-650. I'm willing to accept the possibility that I was charmed by high frequency rolloff induced "pleasant, forgiving, musical, organic sound," but I listened to highs pretty closely, and loud (including the Pixies), and still liked the timbre and decay of the Explorer better than Dragonfly, on cymbals for instance, which isn't precisely an affect induced by lowering highs, I reckon. 

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post #40 of 105
2/26/13 at 2:24pm

Todd from TTVJ has a unit and will be bringing it over tomorrow.  I'll make a measurement and post results.

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post #41 of 105
2/26/13 at 3:34pm
Quote:
Originally Posted by purrin View Post

This is why I asked if anyone has seen published specs from Meridian on this.

 

As to your question: Only from tube amps with switches between low and high output Z. And even then, nothing that high! (The Schiit Lyr output Z is 25ohms, but Schiit does warn you not to use it with certain headphones.) High output Z comes in handy with HD800s, which some people do understandably prefer.

 

I think you got the Schiit amps mixed up.  The spec for the Lyr says that the output Z is 1 olm.  The Valhalla is the tube output one with 25 ohms output Z.

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post #42 of 105
2/26/13 at 5:19pm
Quote:
Originally Posted by Tyll Hertsens View Post

Todd from TTVJ has a unit and will be bringing it over tomorrow.  I'll make a measurement and post results.

 

Man, looking forward for yours as a comparison. 2 samples are better than 1.

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post #43 of 105
2/27/13 at 12:38am
Quote:
Originally Posted by purrin View Post

On a more serious note. The only reason I even bothered with measurements is because this thing sounded so off, at least with the HE500 and UERM. Measurements are a nice way to confirm subjective impressions. Here are some interesting results:

 

OUTPUT IMPEDANCE

 

Objective2 amp: 1.46 ohms

UHA-6HS: 0.95 ohms

Meridian Explorer: 47.95 ohms

 

The output impedance was measured with a DMM and a resistor (used both 50 and 100ohm for two sets to confirm), not with lab grade stuff. Nevertheless, the results should be a good indicator of the actual output impedance.

 

Yup. 47.95 ohms. I measured it again. I couldn't believe it myself. Well, not really. I expected it given the how the ME fubar'd the UERM's frequency response and turned it into an improperly driven LCD2/3. The ME would not be ideal with the HE500 or UERM. The HE500 having lowish impedance (~35-47 ohms), and the UERM ~16 ohms? with uneven impedance throughout the audio band. Maybe the HD800 would fair better...

 

Thanks for your review purrin, I´ve always enjoyed your posts here. Honest and not afraid to go against the mainstream opinion. Exactly what´s needed in this business. I´ve lost respect for most audio review sites a long time ago. Just can´t seem to shake the feeling so many reviews are bought/sponsored. There´s always a new FOTM that´s better than products 5x the price. There must be some hidden warehouse with thousands and thousands of these crappy audio products as according to the press every new product competes with gear 5-10 times its price...

 

Wow... If your measurements are even remotely accurate (even 50% off is not good!), this thing is designed to be used with 300+ ohm gear only and even then is most likely seriously colored. Not even taking into account the coloration (which can be pleasurable, I´m not even in the "all gear has to be neutral" camp), the high output impedance makes this a product fully unsuitable for driving low impedance headphones. I was considering buying one for IEM use, which obviously seems out of the window now. There´s just absolutely nothing even remotely subjective about output impedance: it will lead to higher distortion and mess up the frequency response entirely on certain headphones. I hold a deep dislike for manufactures that don´t disclose their specs - Meridian currently tells pretty much nothing: no crosstalk, no SNR, no power specifications at different headphone ohm levels, no output impedance and the list goes on. Troubling to say the least. I´m still in the market for a portable DAC/amp, but I guess I´ll take a look at HRT Microstreamer instead. They publish the most important specs, in particular the output impedance is 0.5 making is very nice for IEM use. It uses less power and can even be used with a Galaxy S3 for example.

 

PS: This explains why Meridian hasn´t replied to either of my emails I sent to them asking for more detailed specs, in particular output impedance. I even asked a local Meridian dealer who contacted them directly on my request asking for the same thing. No reply yet, this would explain why!

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post #44 of 105
2/27/13 at 1:30pm

No iPad compatibility and high output impedance....doh, it was so promising!  Unless we get further data to prove these two observations incorrect.

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post #45 of 105
2/27/13 at 3:04pm

Got one from Todd the Vinyl Junkie too measure the output impedance----Thanks Todd!

Using a 1kHz tone with 0.410 Vrms output into an open circuit

With 32 Ohm lod voltage dropped to 0.167 Vrms for a 46.56 Ohm calculated output Z

With 150 Ohm load voltage dropped to 0.312 Vrms for a calculated 47.12 Ohm output Z

 

eek.gif

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