How to level match when comparing components?


Simple question-

When you are trying to compare components, say two CD players, it is often difficult to evaluate them effectively unless you can level match the volume levels pretty closely while A-B'ing them back and forth.

What is the simplest way to do this with a reasonable level of accuracy?
mekong56
Go to Radio Shack & get a DB meter.
I have an older one, with analog VU meters.
You might have to get a digital one now....
db meter
Comparing A-B is not very useful. I would listen to several items with A for at least 20 minutes to an hour, then the same items with B... and afterwards consider my feelings about the sound. then perhaps doing them again, in reverse order. A=B in fast flipping back and forth is (IMO) totally useless for a serious evaluation, but if all you want to spend is ten/twenty minutes on a multi-thousand dollar eval... go for it.
I agree with Elizabeth and would take it one step further. Leave A in for a week or a month, then replace with B. Limit music during that time to that which you are intimately familiar with and best represents the range of your musical preferences with some emphasis of material that is demanding of the system. Otherwise A/B is useful on in knee-jerk evaluations of spot differences. How those differences actually play out in the long run enjoyment of your system are not fully understood in a quick A/B comparison, IMO, though some really blatant ones might be easy to eliminate some components from consideration entirely.

As far as matching levels, the original question, you can also get level meter apps for an iPhone and probably other similar devices that would be useful for such a simple task. I think the iPhone app that I have is by Studio Six Digital. One other note, it would be useful to have a recording of white noise (or pink noise) to actually use in association with the meter in order to match the level. It will be easier to use that then a recording of music that is probably changing rapidly. You can probably download something by doing a google search.
In addition to an SPL meter, you will need a pink noise signal. As Jax2 mentioned, using music to level match is nearly impossible.

I agree it takes time to fully evaluate a single component. For comparisons between two or more, direct A/B is necessary. You can't rely on memory, not even for seconds, because the differences are usually very slight. A selection of least 10 to 12 completely different styles of music and recording techniques is helpful. You might notice something different on one recording, yet nothing noticeable on another.

Then you have the real problem. Which do I *like* better, which *is* better?
Then you have the real problem. Which do I *like* better, which *is* better

I hope you are joking. If those two are different in your mind, then you do have a real problem. If you start trying to please someone else, or second guess some "absolute" or objective then you will never be happy with what you choose. The only thing that should be of concern is what sounds best to you, assuming you are going to be paying for it and living with it and enjoying your music through it. I guess if you are buying as a gift for say, Micheal Fremmer, then you should probably be concerned with what he thinks....otherwise it's up to you.
Listening in your home listening room is the best way, and as already suggested, at least a week of each player is best. All else is guessing.
I diagree with ojgalli as to the reasoning.
He is doing an immediate and sudden comparison. relying on attempting to remember a snippet of sound. My (and others) rely on long passages, and NOT so much on memory of the actual sound, but on how the sound made you feel. That feeling is easy to remember. And if it is repeated, the collected feelings of each product with the different music can give one a clear preference, which will last when actually owning the product.
One will remember some of the highlights of the sound, but the meat of the comparison is the emotional response.
An additional thought:
we judge with the thinking side of our brain. We enjoy with the feeling side. (yes this is simplistic, but forgive me)
When we are auditioning, and just using the thinking side, we skip the part of our mind which will be the part that enjoys or dislikes the sound, in the long run.
So by including the feeling side in the process of auditioning, we can fufill the need of our whole mind.
The feeling side needs time to form it's 'opinions' the feelings. Then WITH the feelings included in our decision, we will be happier with our choices.
The OP asked a simple question. The answer pink noise and a db meter.
He/she is not asking whether one should be analytic or emotional regarding component comparisons or what the requisite period of time for a valid comparison.
The OP asked a simple question. The answer pink noise and a db meter.
He/she is not asking whether one should be analytic or emotional regarding component comparisons or what the requisite period of time for a valid comparison.

And (s)he was answered, and it turned into a more interesting discussion. The direction of the discussion is entirely pertinent to the direction of his question. What's the problem?
You cannot level match, unless you are picking a specific frequency, typically 1000 HZ. Music is not so simple. I use a verity of equalizations which are stored in memory and the perceived level changes with each one. Therefore, I agree that long term listening is essential to "evaluate them correctly", which was in fact the original posters declared goal.
Sorry, I misquoted, he said "evaluate them effectively".
All good discussion!

While I would agree that maybe it is not the most effective way to judge on the whole the difference between components, quick a/b'ing can clearly demonstrate differences in frequency extension at both extremes, imaging, and tonality. Also agreed that more thorough conclusions can be drawn by living with a component for several weeks and then switching components in a non A/B manner.

Is there a good pink noise generating test disc out there to help with this?
Is there a good pink noise generating test disc out there to help with this?

Stereophile's test discs have pink noise.

You can also download a file from the Internet for free like those available here and other places. If you only have a CD player, download it and rip a CD from the file.
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If the object is to listen to music, who needs test equipment. There is no better test equipment than two good ears. You will need to compare the two players one at a time, playing your favorite music, in your listening room.
pink noise