Member
Joined 2003
-RT60 is about 400ms
-They were ~80 degree constant directivity. New WGs are more narrow up top.
-ULF not entirely settled, but it will likely be 7-10 db rise from 50Hz-10Hz.
-Still working on this because of the new WGs. Harmon shows about 7db tilt between 100Hz and 10k...with this setup, I've now tried 0 tilt and 6db tilt and the answer (for me) lies between those extremes. Yesterday, I adjusted to 3db tilt, today (etc) I listen.
-Straight line from 100Hz-10k.
I highly doubt my results would be applicable to different speakers in another room so do what suits you, your speakers and your room.
Fortunately my system and room are crap so I can enjoy music almost constantly.
I haven't used my EQ in several months, but I only listen to music at least 3 hrs a day and occasionally 8 or 10. It's strange b/c they measure so well. Dan
but we all have biases, Q.E.D. no one can recognize accutate sound.
hey john k! with all due respect - write to uncle Siegfried for explanation of this quote, or check the context at His website
As I see it He doesn't mean bias...
rather something different
certainly (allmost) all pro/semi pro designers are biased in that significant way - biased towards
and all pro sellers and most audiophiles as well
but there is a lot of people not biased in this particular way at all - common people eg. our wifes in most cases (and they typically even have much better hearing), so I say ask Your wife or even better Your Mom (even if She already uses hearing aids)
most of pro musicians (especially "classical") is not biased in that way - biased towards - either. They are rather biased against such thing as specialty HiFi equipment as such and I do not wonder why...
best regards,
graaf
but there is a lot of people not biased in this particular way at all - common people eg. our wifes in most cases (and they typically even have much better hearing), so I say ask Your wife or even better Your Mom (even if She already uses hearing aids)
most of pro musicians (especially "classical") is not biased in that way - biased towards - either. They are rather biased against such thing as specialty HiFi equipment as such and I do not wonder why...
best regards,
graaf
I gather then that you disagree with what I said earlier, the people who think they are not subject to bias are the biggest fools of all, present company excepted, of course?
not sure why you would insist on trying to prove someone else a fool.
Last edited:
Thank you. Yes, tried to make is not personal and offer it as an empirical observation that the kinds of people who think they aren't influenced (like everybody else), think that because they have poor self-perception. And the more they believe it, the more they are fooled. Perhaps it is nothing more than a tautology, but a useful reminder that we are all blinkered.
Some might say you are wasting your time with listening tests unless they are done blind and ABBA.
Last edited:
I totally agree that audio insiders (that is designers, sellers and audiophiles) who think they are not subject to bias are the biggest fools of all
but outsiders are not biased in that sense because to be biassed it's first necessary to have background upon which particular bias can develop
basically this is how I understand uncle Siegfried's position and I concur
best,
graaf
I listen to ABBA a lot! Actually my kids love ABBA and we always listen to ABBA's "best of" in our car when doing long distances, but of course not only ABBA, also Beatles, Bowie and so on
"ABBA" means you play Sample A, then B, then B again, then A again. That helps control for sequence artifacts.
Sorry.
BTW, who is this ABBA person?*
And double-blind does not mean you close one eye at a time until both are closed.
*kidding
Last edited:
in case someone missed that fact - me was kidding as well
sense of humour is not against audio! great example is John Watkinson -what a great guy!
I was measuring where I listen....at the same off axis point that resembles the power response. I was dual gating with the tweeter region clean and the 400-1k region distinguishable.
I aspire to Geddes but I'm not there yet, I can relate to what Dave is saying.
Hi AllenB
It was mentioned in another thread.
Get the response 'ruler flat'.
Realise it's 'too bright'.
And
Fix it, by bubbleguming a single ply of toilet paper over the tweeter.
Been doing it in recording studios for years.
Quick cheap fix for a scientificaly 'correct', but unlistenable system.
If you want it to look 'pretty' use foam, it kinda looks better.
Simon
Hmm.
What's the rough size of your room and how far is the listening distance from the speakers ? The problem with attempting to take a gated measurement at a far distance like the listening position is that the further away you get the less the time delay between the direct and first reflected signal, and the shorter your gate has to be to avoid room contamination.
For example if we assume that the floor is the nearest boundary to the driver, the floor bounce calculator I've linked to before will work out the time delay of the first reflection:
Floor/Ceiling Reflection Calculator
An example - pretend the driver is 90cm off the floor as is the listener/microphone. With the microphone only 1 metre away from the speaker the time delay of the first reflection is 3.08ms, so maximum gate time is limited to 3ms.
However at a listening distance of 3 metres the delay becomes only 1.45ms, so at this distance you're either limited to a 1.4ms gate time - which won't go anywhere near as low as 400Hz with any accuracy, or a much longer gate time which is contaminated with boundary reflections - and then you're basically measuring the room response, or at least the early reflection parts of the room response.
Dual gate measurement won't really help either - because it uses a much longer gate time for the low frequency part of the measurement this section will be completely contaminated with room response, whilst a 1.4ms gate for the high frequency section of the response wont go nearly low enough in frequency with any accuracy to "join" the low frequency section of the measurement.
Basically what you're trying to measure (on axis balance from 20Khz right down to 400Hz) isn't possible with any accuracy from a typical listening position and distance...
If your high frequency gate time was any longer than ~1.4ms (depending on your listening distance) your tweeter response is still contaminated with at least one major room reflection, so equalizing this measurement flat would more than likely result in a boosted on axis treble response due to the fall in high frequency energy in the off axis response reflecting from the floor...
Last edited:
No worries, I was taking liberties. For a more palatable demonstration of my comment:
Agreeing to disagree
With a bit of what follows my sig below, this thread might just get places.
FWIW, as I expressed at the start of the thread, I also take Dave's design approach, and John's. I target a specific on axis (usually close to flat but with some tilt) try and tune the off axis to be smooth without deviating from on axis targets and then only add on axis deviations if the design isn't still "right".
However I don't use a fixed reference to compare against as Dave does when making the last very fine tweaks. I'll throw a new idea into the conversation: I minimize how annoying the speaker is.
We haven't talked about this yet, but there are two types of valid DBT audio quality scales: mean opinion scores (typical preference testing) and annoyance testing (usually relative). The ITU-T recognizes both and has published test methodologies for both. These scores often track with each other (higher preference usually results in lower annoyance) however it's not a perfect correlation. We all know that aspeaker may sound great in short to medium term listening but less so after extended listening. I design to minimize this annoyance.
The end result is a design where the flaws are more subtractive than additive. I'll give an example. I recently heard the RBR kit and it did many things right, but I instantly heard an 800Hz peak. I called it, there's an 800Hz peak there. And its a bit bright. Low and behold, we measured it and there was an 800Hz peak and the top end was a very small bit elevated from flat. I can see many liking this but it annoyed me.
So, designing to an annoyance scale would remove all these peaks and tilt the top end down a bit. Is it less accurate? Technically, if we just assigned an "error function" against flat, yes. Realistically, I certainly don't think so since listening to live music is never annoying for me. Is the less bright speaker with even no small peaks perhaps a bit less resolving, and would some people "prefer" it less for those reasons? Maybe. Probably.
In summary, I design to minimize annoyance, not maximize preference. They are usually one in the same, but not always and especially so at the end of the tweaking stage. If the design handles diffraction properly and is resonant free, minimizing annoyance happens through subtle alteration of on and off axis frequency response.
Dave
"The first step is recognizing the problem. We are biased. I am. You are. Everybody is.
The next is to get out of the warm bath. Look for information that contradicts your views and give it real consideration -- while remaining aware that the brain that is doing the considering is biased against it.""
Edit: I love my children. I never play Abba.
Last edited:
Oh, you had to go and mention that, Mr. Wise Guy.
It was NOT a success.
Family trip, my mother's idea.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.