The Advent Loudspeaker
- Thread starter Zilch
- Start date
chameloman72
Active Member
These must be played through a good amplifier that is for sure!! They sounded kinda crappy played through my SX 1250 but when hooked to the 9090DB they sang like canary!!
markus
Master Procrastinator
I like my original large advents off the floor when I listen to them, and somewhat away from the walls, so I guess thats a yes . . . :scratch2: I've also done away with the entire factory crossover, just using 16 uf of old power supply oli caps on the tweeter.
I am most definitely staying tuned :thmbsp:
legalalien
Well-Known Member
Kingbubba your description of what you're hearing from the NLA's is not something one would normally use. Though I have no reason to doubt you on this I wonder if there is something else amiss, have you checked the polarity on the internal wiring or are the fried egg tweeters in fact "fried"? Look I understand that all speakers are going to sound a little different from one person to another but the Advents 1# attribute is their smooth mellow sound and this is NOT something you seem to be experiencing. I run mine with a Marantz 2275 which is known to have a smooth and warm sound but I know of many people using a wide variety of amps with the Advents and having very good results. One last question, have been able to hear them in another setup to see how it compares to yours cause I think this will affirm or contradict what you are hearing with yours.
Had two pair of these, and wasn't particularly impressed. They are OK, but not great to my ears at least. I tried the recap and fiddled with placement, but sold both pair in the end. An interesting thread for sure -- very interesting the measured difference with grilles on/off, especially for those of us who run our speakers grilles off as the norm. I'm looking at my KEF 105s right now, wondering if I'm missing much by running them without the stock grilles in place... :scratch2:
I'm surprised to discover that the grille also masks upper midrange anomalies coming from the woofer, though I now see that opening is also "engineered." Look to the design of the grilles for clues.
There are certainly "issues" with playing these early Advents with the grilles off, and they're not trivial. Atkinson found the same with the later Smaller Advent.
Recap:
Crossovers in these The Advent Loudspeaker - Utility are Rev2, 16/8/3. The nonpolar electrolytic caps removed measure 17.68 and 9.02 uF for 16 and 8 uF respectively.
I replaced them with a 16 uF and 3.3 || 4.7 uF Solens. Did it make a difference in the measurements? Perhaps 1/2 - 1 whit worth of one:
Did I do it right? Here's the three switch adjustment levels:
Compare to the original measurements on this unit here:
http://audiokarma.org/forums/attachment.php?attachmentid=94449&d=1213056841
Does it sound different? We'll see in the A/B. I've got one stock and one recapped, now.... :yes:
Crossovers in these The Advent Loudspeaker - Utility are Rev2, 16/8/3. The nonpolar electrolytic caps removed measure 17.68 and 9.02 uF for 16 and 8 uF respectively.
I replaced them with a 16 uF and 3.3 || 4.7 uF Solens. Did it make a difference in the measurements? Perhaps 1/2 - 1 whit worth of one:
Did I do it right? Here's the three switch adjustment levels:
Compare to the original measurements on this unit here:
http://audiokarma.org/forums/attachment.php?attachmentid=94449&d=1213056841
Does it sound different? We'll see in the A/B. I've got one stock and one recapped, now.... :yes:
Attachments
asoundhound
Definitely Low-fi
almost everything+advent=ecstacy
superdog
AK Member
I found that they sound better with the grills on.The highs can be harsh if not tamed by the controls.I find that in my listening experience that they are a very good speaker but I wouldn't go so far as calling them a great speaker.Right now listening with Luxman R-117.
I have to agree that the horn just doesn't look right in the Advents! LOL!
But given the low crossover point it does make sense, and it is of the newer waveguide variety. I had the idea of using a waveguide type horn tweeter myself for the Large Advents as I stated here: http://www.classicspeakerpages.net/IP.Board/index.php?s=&showtopic=2767&view=findpost&p=66647
Zaph does a nice job here: http://www.zaphaudio.com/hornconversion.html
But your find of those fine performing low cost parts is excellent, saves some time over Zaph's design that requires modifications. I might try it sometime.
You're S'POSED to be running with the grilles on....
My first runs are somewhat higher than 1 kHz, more like New Advent. The original Advent woofer has some issues at 1 kHz, as I've shown. The glitch in the impedance curves may be from that; I need to investigate more. I'm using them primarily because they fit the hole in the cabinet, and because it's a rational "first order" mod, if it can be made to work.
JBL's been using waveguides on dome tweeters in their commercial product lines for quite some time. As you observe, though, the low-frequency capability has to be available from the driver to begin with. How effective "loading" with a fast flare waveguide might be to help in this regard is indefinite, and dubious.
There are more I haven't shown yet. I've found some surprises in working with JBL's latest PT designs; they're using them at lower frequencies than I would anticipate is possible with such small dimensions. I need to get the running active here and dial the frequency around to determine the practical limits.
The low frequency limit has several factors to consider as I'm sure you know, Fs, horn flare rate, and Xmax limits. We should keep in mind that the manufacture's suggested limit is usually for sound reinforcement in large halls where the SPL requirement is much higher making the Xmax limit a significant concern. This would be less of an issue in the home environment.
Distortion tests vs. SPL would help determine the real lower limit.
You mention issues with the woofer around 1 KHz, have you considered how the cavity formed between the grille frame and front baffle might be contributing? Poly fiber or wool in that space might help reduce the effect.
Pete B.
Distortion tests vs. SPL would help determine the real lower limit.
You mention issues with the woofer around 1 KHz, have you considered how the cavity formed between the grille frame and front baffle might be contributing? Poly fiber or wool in that space might help reduce the effect.
Pete B.
That is odd. You'd think that woofer coupling (from having them close together) would cause LESS cone motion, which would make for even LOWER impedance (less back EMF)...
It'd be interesting to find out WHY this is taking place. Zilch, I assume you're using reasonably heavy speaker wire, and not "angel hair" wire, right?
Regards,
Gordon.
It'd be interesting to find out WHY this is taking place. Zilch, I assume you're using reasonably heavy speaker wire, and not "angel hair" wire, right?
Regards,
Gordon.
14 or 16 Ga. in ZilchLab.It'd be interesting to find out WHY this is taking place. Zilch, I assume you're using reasonably heavy speaker wire, and not "angel hair" wire, right?
This is small-signal impedance; maybe I'll do it with CLIO and give them some "juice."
The resonance peaks are approximately halved, and primarily resistive, perhaps; the rest being dominated by inductance, in parallel?
Am I the first ever to actually MEASURE the impedance of two speakers connected in parallel?
