 
|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
|
|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
74.83.38.154
In Reply to: RE: Which is why listening is important... posted by Doug Schneider on February 09, 2023 at 19:53:35
At the risk of beating a dead horse, he wrote in his conclusion, after briefly discussing the speakers' reproduction of the specific frequency ranges, "the issue was in the midbass," and "Alta Audio has fulfilled the promised they made with their XTL bass loading," which I presume reflected his statement in the body of his review that "A positive for the Alecs was bass depth: the Altas did play lower in frequency and with more output in the very lowest registers." I don't know what he meant by "the very lowest registers," but I have an idea.
So, again, I think simply using the word "bass" implies an issue with the entire bass range, whereas I think Mr. Fritz's issue with the speaker, as he wrote in his review, was with the midbass.
Every speaker has colorations to one degree or another. We are blessed with an excellent small jazz club in our mid-size midwestern city, and so I spend two to three evenings a month listening to live acoustic jazz from some of the genre's top performers, as well as the occasional acoustic rock music in another small club. Consequently, I can generally pick up tonal colorations in a speaker fairly quickly. I did not hear any significant tonal aberrations or colorations in the Adam listening to Keb Mo playing acoustic blues at Axpona. But I agree that hearing one piece of music at a show is not enough to make a definitive conclusion. I can only say that the Adam tonally accurate on that one piece of music. On that piece of music I did not hear any unnatural glare which passes as detail for many audiophiles. Based upon my experience at Axpona, were I in the market for a speaker, the Adam would be on my list to further explore. Where my explorations would lead, I cannot say.
By the way, at the risk of demonstrating my laziness, did Alta Audio send another sample?
Follow Ups:
Well, like I said, there are some strange ideas in the ideas -- the strangest being choosing not to damp the internals of a transmission-line enclosure. People can decide for themselves if it works -- i.e., listen -- but it shows up problems in listening and measuring. Those upper bass resonances are exactly what you'd expect to hear.
About six months ago we published a video about transmission-line loading with Toby Ridley, one of the main acoustical engineers at PMC. He explains the concept behind TL loading.
Doug
Good point about damping a transmission line. In fact undamped transmission lines existed before transmission lines. They were called labyrinths. And when damping(long hair wool initially) was added to a labyrinth in the early 1960s it was called a transmission line.
At first the idea of a line sounds simple but there are problems with details. Folding lines causes resonances at the folds in classic designs. And in fact even a straight line also has resonances. This is why lines are often reduced in area as the line lengthens; it reduces the strength of the resonances. Adding damping makes the resonances less and by the way also increases the acoustic length of the line by reducing the speed of the wave lengths in the line.
Very good points!
And from what we can see in the measurements (and listening), these resonances are exactly what one would expect from such a design -- and what most try to avoid.
Doug Schneider
SoundStage!
By the way, I've never seen it done but the man credited with the transmission line said the end could just as well be closed as well as open. I knew Bud Fried well and his comment was lines were open to use the extra bass of an open port, essentially like a port does in a reflex box. I wonder what would happen with a closed line with the total volume chosen for a tight closed box(I'm a big fan of low Q closed box bass).
The nearest thing to a closed line I know(albeit not really a closed line was the D'Appolito SEAS Thor kit where the line was stuffed enough it was just a pressure release but not a bass source, effectively a combination of a transmission line and a variovent(aperiodic). Perhaps that is an interesting line to explore.
Hi Hahax, I think you just described in a scientific way,less the transmission line part, why the Dynaco A-25 morphed into the A-35 which had lower bass and the best of both worlds you described, a variovent or resistant port in a closed box...Mark K.
Great speakers but what you lose without the line is theenergy absorption of the line spread over a long distance instead of basically in one step as in a box with damping.
It is interesting that the variovent works both venting to the outside(A25) and also venting from one box(with the driver) into a second box.
By the way what a variovent does(at least if it only pressure releases with no sound getting out) is to lower the Q of the speaker. The driver/box resonance stays the same but the Q gets lower resulting in a bit less bass but tighter, more defined bass.
| FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
||||||||||||||
This post is made possible by the generous support of people like you and our sponsors:
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2025, Audio Asylum, all rights reserved ]
