Gedlee on distortion

[fpitas]

Re: Gedlee on distortion

At the risk of inciting flames, it seems we can all agree that intermodulation performance is a much better predictor of audible differences than THD alone.

[rickcraig]

Re: Gedlee on distortion

Not surptised at all that the two you got along well together.

Thanks for your kind comment.

In regards to Earl I'm sure we would've disagreed if the conversation went long enough.

[Face]

Re: Gedlee on distortion

At the risk of inciting flames, it seems we can all agree that intermodulation performance is a much better predictor of audible differences than THD alone.

http://www.aes.org/e-lib/browse.cfm?elib=2962

[Deward Hastings]

Re: Gedlee on distortion

it seems we can all agree that intermodulation performance is a much better predictor of audible differences than THD alone.

They are different views of the same thing . . . there is no intermodulation without the same non-linearity that also produces harmonic distortion of a single tone. Where they differ (in a complex music signal) is that the harmonics tend to be "euphonic", and blend in with or be masked by the desired sound (except the higher order ones, as from zero-crossing distortion), while intermodulation products tend to be more broadband and unmasked, so we hear them as a background "grunge" and "harshness". This is why the Phi-tone test (mentioned upthread) is so much more visually revealing of what we actually hear, even though it is hard to quantify the result in a single number.

[craigk]

Re: Gedlee on distortion

so back to the phi multi tone testing for a moment. how do you determine that the cable used to transmit the the test tones is not the issue ? do you measure the cable then use tones that are not creating issues in the cables and then not use tones that are harmonics of those tones that cause issues ?

[Bob Brines]

Re: Gedlee on distortion

Cables will only be an issue if magic pebbles are set on the speakers.

Bob

[Deward Hastings]

Re: Gedlee on distortion

so back to the phi multi tone testing for a moment. how do you determine that the cable used to transmit the the test tones is not the issue ?

The cable is not the issue. Look at the signal at the generator and then at the input of the dut. Then look at the output of the dut.

When testing a driver there's always the question whether one is seeing the driver or the microphone . . . but that question applies to any distortion or frequency response measurement.

[craigk]

Re: Gedlee on distortion

The cable is not the issue. Look at the signal at the generator and then at the input of the dut. Then look at the output of the dut.

When testing a driver there's always the question whether one is seeing the driver or the microphone . . . but that question applies to any distortion or frequency response measurement.

I was curious because looking on the phi tone website he also tested cables with this method and I was just curious how you sorted the distortion information between the cables and the speakers.

[carlspeak]

Re: Gedlee on distortion

It's too bad you're so far away. Ever since I heard Mundorfs, my dream is to use them in a "end all, be all" design, but I'm afraid to drop the money. If only I could hear yours

Well, you could call me when I'm sitting in the sweet spot and listening to some tunes and I'll point the phone toward the speakers! :rolleyes:

If the cost of the Mundorf AMT's is an issue, have you considered getting a pair of the B652 AIR's. There is a small AMT tweeter in them that's quite amazing but probably not a Mundorf. In any case, the tweeter is a good starting place for modding that speaker into a very nice sounding mini-monitor. See the the link I provided in the first post of the this thread.

[Deward Hastings]

Re: Gedlee on distortion

I was just curious how you sorted the distortion information between the cables and the speakers.

For a start there is a difference of several orders of magnitude. You have to work at it (or have VERY bad cable) to see cable effect at all (and I obviously disagree with Risch about the importance, and even the meaning, of those measurements).

[mattsk8]

Re: Gedlee on distortion

Well, you could call me when I'm sitting in the sweet spot and listening to some tunes and I'll point the phone toward the speakers! :rolleyes:

lol! "These don't sound quite the way I remember them sounding" :p

If the cost of the Mundorf AMT's is an issue, have you considered getting a pair of the B652 AIR's. There is a small AMT tweeter in them that's quite amazing but probably not a Mundorf. In any case, the tweeter is a good starting place for modding that speaker into a very nice sounding mini-monitor. See the the link I provided in the first post of the this thread.

I know there are plenty of options, but I'm pretty picky and the only AMTs I've heard that had everything and still sounded natural were the Mundorfs; I was told they invented the AMT (not sure if that's true?). From what I remember, they had amazing clarity without sounding too thin, and they still had great body everywhere while maintaining that glow I look for in a tweeter. From what I've heard in a lot of tweeters, you either get great body but sacrifice the glow and distinction, or you get great distinction but they tend to be a tad thin; those seem to give everything and sacrifice nothing. But, my opinion is from a brief listen, so I'd love to spend more time listening. What are your impressions on how they sound?

As far as cost goes; it isn't as much about whether the cost is an issue, it's more about whether it's the best choice when I'm going for the ultimate speaker if that makes sense. If or when I do it, I don't want regrets, so which one and where it's implemented is definitely key ;).

[carlspeak]

Re: Gedlee on distortion

lol! "These don't sound quite the way I remember them sounding" :p



I know there are plenty of options, but I'm pretty picky and the only AMTs I've heard that had everything and still sounded natural were the Mundorfs; I was told they invented the AMT (not sure if that's true?). From what I remember, they had amazing clarity without sounding too thin, and they still had great body everywhere while maintaining that glow I look for in a tweeter. From what I've heard in a lot of tweeters, you either get great body but sacrifice the glow and distinction, or you get great distinction but they tend to be a tad thin; those seem to give everything and sacrifice nothing. But, my opinion is from a brief listen, so I'd love to spend more time listening. What are your impressions on how they sound?

As far as cost goes; it isn't as much about whether the cost is an issue, it's more about whether it's the best choice when I'm going for the ultimate speaker if that makes sense. If or when I do it, I don't want regrets, so which one and where it's implemented is definitely key ;).

Hey, don't worry about regrets. Just go for it. Look at my signature line. 3 iterations of the Intimates before I was satisfied.

[SpeakerScott]

Re: Gedlee on distortion

Geddes is a smart guy with a lot of knowledge in this field, and a lot of good information on acoustics. He is also quite prone to playing semantics games and spinning information to precisely fit his "highly acclaimed Gedlee loudspeakers". When he is wrong, don't expect an admission, which is just silly. (I was in a discussion with him on another forum on modeling diffraction and he was just wrong about the importance of modeling the first baffle peak in a simulation, which his model leaves out. The rest of us moved on.)

Regarding his comments on distortion; I don't know if he is just being very precise and narrow in his statement (but he doesn't really infer this), if he's just mistaken in his views, or if he is purposely spinning information to suit his needs at the expense of a larger truth. Whatever it may be, he knows exactly how he wants his comments to be interpreted.

As for me, after taking lots of distortion measurements on a range of different drivers, and then playing and listening to these drivers under different conditions, I am sufficiently satisfied that higher distortion components produce easily audible effects and I can hear very quickly what it is and what it sounds like. Consequently, very low distortion drivers actually do sound better in a number of ways to me, but it does depend on drive level and where that audibility enters the picture for that particular driver and crossover combination. Still, for some drivers, this threshold is quite low. I am satisfied enough based on my own testing that it wouldn't really matter to me if someone else stated something otherwise.

Jeff B.

My interactions with him have been very similar. We had quite the discussion over my DIY Synergy horns. His take was that it can't possibly sound good. I still don't know if he's heard a quality Synergy horn (real or DIY) or has any interest in having his ideas/models challenged. I hope I'm wrong, as a researcher you *always* want to find the flaws in your theories.

Scott

[mattsk8]

Re: Gedlee on distortion

*Warning* Thread deralement

Hey, don't worry about regrets. Just go for it. Look at my signature line. 3 iterations of the Intimates before I was satisfied.

Looking at your links I just saw that you replaced the XT25 with those Mundorfs, and IMO beating that XT25 in terms of SQ is a pretty tall order. I love the XT25, the only area I would complain (and this is a stretch) is that it has a kind of "fuzz" in the upper frequencies, other than that it's nearly perfect. In your opinion, how do those Mundorfs compare to the XT?

[carlspeak]

Re: Gedlee on distortion

*Warning* Thread deralement



Looking at your links I just saw that you replaced the XT25 with those Mundorfs, and IMO beating that XT25 in terms of SQ is a pretty tall order. I love the XT25, the only area I would complain (and this is a stretch) is that it has a kind of "fuzz" in the upper frequencies, other than that it's nearly perfect. In your opinion, how do those Mundorfs compare to the XT?

I think the intimates have a little more life. In my little 13X13 room and sitting in the sweet spot approach the mids and highs of a good electrostatic. The Vifa's measured and sounded very good though. It's there in the link I provided. I'm probably going to put them up for sale in the PE classified in a bit.