Review: Portable amp roundup! 56 portable amps reviewed and compared - FINAL update 12-20-10... - Page 129  

As a beginner, I am not very happy with this compilation as it provides too much info. A poor beginner in this hobby can get overwhelmed. How I wish that"product A is slightly different than product B, and they are both outdone by product C to thrice the price"
Anyhow, I guess based on what I have read here, going for a Meier 2Move or an Ibasso D1/D2 or a Tomahawk, one does not go very wrong.
I do appreciate someone taking the time and effort to create a thread like this. Thanks :-)

keep up the good work SKY!!

You're absolutely correct: I own the 2Move and the Tomahawk and have heard the iBasso D2 thanks to Mrarroyo and can tell you for the money, any of these three would be a wise purchase. Check the F/S forums and buy used or go for new. Any one of the three will serve you well.

Level-matching for listenings tests

[QUOTE= ...Listening was done with the levels matched to within 1db using a RS SPL meter, so that the listening volume level was identical with each amp....QUOTE]

Level-matching ¡¡¡ 1 db !!!, please Skylab more technical seriousness. Ideally, playback level is 0.1 or max. 0.2 db. Level-matching is crucial. Slight level differences between products can lead to the wrong conclusion. The ear's sensitivity to bass and treble increases disproportionately with volume. It is to say, we hear more bass and treble when the music is loud. If amp A is played louder than amp B, amp A may sound brighter, more detailed, more forward, more dynamic, and have more bass. If amp A has a soft treble, lacks detail and has a lean bass balance. if the level is not exact, these differences we will not be able to detect them.

[QUOTE=Jaume;4197835] As another voice of defense, the fact that he level matches at all is commendable, and above and beyond what most do. If everyone level matched to that extent, reviews here in general would be a lot more credible.

I do use a dB meter to match when I review. I find that using my ears gets me almost as close as the meter does.

But it really does not matter what each person does or does not, there will be some who do not want to believe and attack. Sometimes because they do not have anything to say.

I use a cheap SPL meter also to level match, and mostly to confirm to myself that I'm not listening too loud.

I find reviews or comparisons between items that aren't level matched are highly unreliable, because in my experience even a relatively small increase of 2-3 dB drastically changes the sound.
I always wonder when people compare gear if they aren't just hearing the difference in volume, and not actual sound quality, especially when there are those mythical "night and day differences".
For this reason alone, I wish I had a stepped attenuator on my amp instead, but oh well.

Since Skylab is doing fairly accurate level matching when reviewing, I don't see what the big deal is.

Off with his head!!! Let it be known throughout all the Head-Fi Kingdom that Skylab doesnt keep matching below 0.0001db!

Jude call the gaurds!

Personally i think he reviews well, and pretty neutral for a ((((BASSHEAD))))

Have to agree. The variety of reviewers all do a very good job and approach it as professionally as possible given what time they have and the ability of the SPL meters to level match.

Keep up the good (very good IMHO) work, portable amp reviewers.

This is the meter I use RadioShack.com - Home Entertainment: Accessories: Audio accessories: Sound meters: Digital-Display Sound-Level Meter

I bought it originally to test the volume levels of different suppressed firearms, to verify they were hearing safe - I would velcro it to my rt shoulder, so I knew what the SPL was at the ear, but I don't think it was particularly well suited to that endeavor.

I looked up my specs, and my meter is only a +/- 2db at 114 db spl. So I could repeat the test producing a consistent 114db noise each time and get anything between 112-116 on the readout.

I don't know if it is better or the same at 80db, but that means it "could" read 80 when it is as low as 78 or as high as 82db.

However, If I have two amps reading 80, but they are really 4db apart, I KNOW I CAN hear the difference, and typically I can hear a 1-2db difference. So, my ears tell me if works better than the specs say it does.

Battery.........................................9-volt Alkaline
Microphone.........................Electret Condenser
Range......................................50 dB to 126 dB
Accuracy............................± 2 dB at 114 dB SPL
Reference...................0 dB = 0.0002 Micro Bar
Weighting......................................... ....A and C
Display Response......................Fast and Slow
Signal Output:
Voltage...................1 Volt Peak-Peak Min.
(Open Circuit, Full Scale at 1 kHz)
Impedance..............10 Kilohms Min. Load
Distortion..............Less than 2% at 1 kHz.
0.5 V p-p Output
(Input: Mic Out, Output: 10 Kohm)