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View Full Version : The 2.3TL eagle has landed!!


solidclub
12-24-2006, 07:43 PM
Gday Polkies from Australia,

Upon Darqueknight's excellent suggestion, I have recently acquired
a set of MINT (and I mean MINT, I cant believe these things)
SDA-SRS 2.3TL's. They arrived yesterday in fact, to my home town
of Sydney, AUSTRALIA, after travelling more than 16000 kilometres
from NEW HAMPSHIRE, US. Surely this would have to be the longest
distance that anyone has had these shipped? :)

Some of you guys probably spied these on ebay, and it didnt take
much to convince me to buy them after speaking with the seller.
I must say a word in support of Fedex on this one, as inconsistent
as they may be, they got it right.

Now onto a question. I am running these (at a friends place) at
the moment with a PA amp which is rated at 500W per channel
at 8 ohms. I havent had the dial past Midday at this point, but
when it was there, they were shaking the house.

Can someone explain the concept of tweeter protection, or direct
me to a relevant thread? I listened closely to each tweeter, and
it appeared to me that more volume was coming out of the top
tweeter than the lower two. How does the crossover distribute
signal to the tweeters? I noted that as I increased the volume,
the lower tweeters seemed to come to life a bit more.

Is there a way that I can determine that each speaker is working
properly, or is this simply done by ear?

Thanks and I look forward to hearing from you all!!

Alex.

DarqueKnight
12-24-2006, 09:11 PM
The tweeters of the SRS 2.3 TL (and the SRS 1.2TL) are arranged in a point source array where each tweeter plays a different part of the frequency spectrum. Therefore, the sound you hear from each tweeter will be different.

Here is a quote from a SRS TL series brochure:

"Additionally, the SRS 1.2TL and 2.3TL utilize Polk's Progressive Point Source technology to maintain constant vertical directivity of mid and high frequencies, which prevents undesirable beaming. As frequencies increase, the tweeter array adjusts its radiation area and eventually becomes an ideal point source at the very highest frequencies, eliminating frequency interactions and reflections between multiple drivers."

Most SDA's use a fast acting self-resetting semiconductor tweeter protection device (polyswitch) to prevent the tweeters from being damaged by a very high amplitude or distorted signal. I removed the polyswitches from all of my SDA's because I found that it diminished high frequency detail by a small amount.

If you are using a high quality amplifier of adequate power and will not be listening at excessive sound levels, you can safely remove the polyswitches. Later versions of the SDA SRS 3.1TL did not have a polyswitch or any other type of tweeter protection.

beardog03
12-24-2006, 09:46 PM
WOW !
Australia !

Way to go on getting some outstanding speaks !

DarqueKnight
12-24-2006, 09:48 PM
Is there a way that I can determine that each speaker is working properly, or is this simply done by ear?

Testing each individual driver is a time consuming, but worthwhile task. Here is what I do.

1. Push the passive radiator in and out several times and notice the motion of the mid-woofers. They should move in and out smoothly with no "scratchy" sound. If you hear a scratchy sound or if a driver is not moving or moving much differently than the others, it should be replaced.

2. For sound testing of mid-woofers, I use a two conductor cable with banana plugs on one end and insulated alligator clips on the other end. I use this cable to connect to the output of a small amp in my test rig (amp/preamp/CD player). After connecting a driver to the amp, I turn up the volume on the preamp just enough to hear the sound clearly.

3. For sound testing of tweeters, I use the same two conductor cable with banana plugs on one end and insulated alligator clips on the other end. This time I attach a 7.5 ohm resistor to the positive terminal of the tweeter and then attach the positive lead of the cable to the other end of the resistor. Then, test as in part 2.

I use this cable to connect to the output of a small amp in my test rig (amp/preamp/CD player). After connecting a driver to the amp, I turn up the volume on the preamp just enough to hear the sound clearly.

For test purposes, I use music CD's as well as "test" CD's that contain frequency sweep signals and other test signals.

Have fun and congrats on your purchase and their safe arrival.:)

riglehart
12-25-2006, 12:24 AM
You might laugh at this, but it will work if you are concerned a tweeter isn't working.

Take a roll of toilet paper and put the tweeter on one side and your ear on the other (listen through the hole). You will hear the tweeter in question without interference from any of the other tweeters or drivers. It's a quick and dirty way to tell you if it is working.

I used this method when I was also wondering if the tweeters where working correctly on my 2.3TL. Found two where bad.

I had the same questions about my 2.3 when I get them. The top tweeter seems to pull most of the load, at least at low/moderate listening levels.

Ricardo
12-25-2006, 12:56 AM
Alex,

Congratulations on your new pair of SDA's; that's definitely a long way from NH to Sidney.

schwarcw
12-25-2006, 01:21 AM
Congrats on your new 2.3TL's! The pro amp is okay to get acquanited with the 2.3TL's, but eventually you're going to want something smoother. Per the PM you sent me, if there is anything I can do please let me know.

I would suggest buying a copy of the "SDA Compendium" from Darqueknight. It has a wealth of information about SDAs small and large. Kind of the Bible for SDA owners. Maybe Raige will send you some information.

Enjoy your speakers and please post any questions you have!

minipete
12-25-2006, 01:48 AM
Hey guys!

Thanks for your replies. Here are some photos for your amusement.

And I think I will invest in the SDA compendium from Darqueknight.

Enjoy!

ps the room that you see the speakers in is not the room that
they will end up in. The room belongs to my friend who owns the
RTA 12B's in the centre (oh, arent they cute? :) ). Clearly
the room is not big enough for the SDA's. I had to set them
up somewhere. Hell, I couldnt let them sit in those boxes over
Xmas!

solidclub
12-25-2006, 01:53 AM
Hey guys,

That last post with the username minipete was actually me.
Im on my friends computer and he was signed in. DANG!

Anyhow, he is a Polk owner (the pair you see in the pics),
who lives in Sydney right near me.

Thanks!

Alex.

F1nut
12-25-2006, 02:16 AM
Nice Christmas gift to yourself. As Raife pointed out, your tweeters are working as they should be, enjoy!!!

SCompRacer
12-25-2006, 03:18 AM
That last post with the username minipete was actually me.




Congratulations on your well traveled speaker acquisition and welcome to the forum!

BTW, Nice shirt!

solidclub
12-25-2006, 07:21 AM
Hey guys,

After a long period of listening, I noticed that the top tweeter in the
left speaker is cutting out, and a crackling/static noise
can be heard at times coming from the tweeter. I heard this yesterday,
but the speakers worked fine today, up until now. I have determined
that it is coming from the speaker somewhere, by checking each of
the components for a bad connection/fault. Could this problem be a
polyswitch which is on the way out? When the tweeter works it sings
like a bird and sounds fanatastic.

Thanks, Alex.

amulford
12-25-2006, 09:07 AM
I don't think that would be a poly switch. It would just cut out. It could be a loose connection to that tweeter. I would check those first.

I concur with Carl about the amp. It'll work for now, though.

Welcome to the Club, and congratulations.

F1nut
12-25-2006, 01:55 PM
Agreed, not the polyswitch as all the tweeters in that speaker would go out. As Anthony stated, it could be a loose wire, but I think the tweeter is bad. If they are the original SL3000's that's very possible.

DarqueKnight
12-25-2006, 04:02 PM
After a long period of listening, I noticed that the top tweeter in the left speaker is cutting out, and a crackling/static noise can be heard at times coming from the tweeter.

As you noticed, the top tweeter does most of the work. It is also the one out of the three that does not have a resistor in series with it. Therefore, if some electrical abuse occured in the past, the top tweeter is going to take the brunt of the hit. If it is the tweeter, what you describe sounds like the tweeter voice coil has been slightly damaged so that it can't reproduce certain frequencies properly. Damage to the tweeter voice coil could also have been caused by a direct impact during packing or shipping. Everything wears out in time, and it could also simply be a case of a tweeter that has reached the end of its life, although, there isn't any hard data on the life expectancy of those tweeters because it depends on how and how much they have been used.

You can always try switching tweeters around to see if the problem remains in the same place or if it follows the tweeter. If you switch the positions of the top and bottom tweeter and you still hear the noise at the top, and loose connections and amplifier problems have been ruled out, something is wrong with the crossover.

schwarcw
12-25-2006, 08:23 PM
I agree with Raife, swap the tweeter and see if the crackling follows the tweeter.

Great picture! Congrats on your new 2.3TL's!!

Carl

Refefer
12-25-2006, 09:17 PM
Excellent purchase! You have made more than one music lover envious today ;)

Dare I ask how much shipping was from literally half way around the world?

Mike Reeter
12-25-2006, 09:18 PM
Congrats on your new 2.3TL's... they are a hellofa speaker...

Welcome to Club Polk..You have come to the right place,there are many SDA authorities here that are "full of" information:D

solidclub
12-26-2006, 04:48 AM
Hey guys,

I tried the speakers and they did the same thing again today.

I removed the "problem" tweeter and checked the connections.
They seem fine. I tried them again and the same thing occured.

I then removed the "problem" tweeter and swapped it with the
tweeter directly below it. The same problem occured, which
by Darqueknight's logic tells me that the problem is not with
the tweeter itself.

I guess the next option is the crossover. I mean, what else could it
be? When operating, even at low volumes, the tweeter signal is
intermittent, and comes through with a static/crackle noise like
its struggling to break through.

Are there any other internal connections that I should check
which relate to that particular tweeter position? Also where is
the crossover located and how do I access it?

Thanks SO MUCH guys for all your help!

Alex.

danger boy
12-26-2006, 04:53 AM
Alex.. it could also be a problem with you amp/receiver. when it cuts out and crackles like that.. a common problem of intermittent audio. Especially noticed at low volume, "punches through" as volume is increased.

DarqueKnight
12-26-2006, 05:38 AM
Here are some things to check:

1. Is your amplifier a "common ground" design? SDA's require common ground amps. If you are unfamiliar with the term "common ground", there are many references here on the forum and on the Internet.

2. Are the connection straps (wires) between the upper binding posts (high frequency) and lower binding posts (low frequency) clean, securely attached to the upper binding posts, and free of any corrosion?

3. The crossover is accessed by removing the passive radiator. After the screws are removed, you may need to gently pry the rim of the passive radiator away from the front of the speaker. Sometimes they fit tightly in the recessed cutout. The individual driver wires are attached to the crossover circuit board by plug-in wiring harnesses. Make sure these are fitting securely.

solidclub
12-26-2006, 07:05 AM
Hey guys,

Thankyou Darqueknight once again for your suggestions. Ill set the
scene for you.

Firstly I checked the links between the wiring posts and confirmed
that they were clean and making a tight connection.

The amp with which my friend "minipete" runs his RTA 12C's with is
an Adcom GFA-585. I have primarily run the speakers thus far with
this amp. Last nite we had my PA amp hooked up to the
speakers and they ran without a problem. Come to think of it,
I may have only encountered the problem when running the Adcom.

I have since reconnected the speakers to the PA amp, and from what
I can hear the tweeter is back to working again. I listened closely
at moderate volume and believe I heard a tiny amount of static or
crackling noise in the tweeter but I cant hear it now. Im probably
just imagining it anyway, being a pessimist. Im crossing my
fingers, as Im anticipating it dropping out at any second.

Is the Adcom a non-common grounded amp? Or is it an inconsitent
amp with which to run 2.3 TLs?

I will continue to run the speakers with the PA amp and let you
know how it goes.

Thanks again!

Alex.

solidclub
12-26-2006, 08:03 AM
In answer to Refefer's question about shipping cost.

I have a sweet deal with a mate who works for Fedex.

I was able to ship these at 25% of the regular price.

That worked out to be $430 US all up.

You probably couldnt get them from New Hampshire to
New York for that much (maybe thats an exaggeration?).

I also managed to evade any duties from Customs at this end,
as they were all in holiday mode and refused to start up their
work stations! (so I'm told). Gotta love the festive season!

Well, lucky me, and as you can see in the photo, Im
extremely pleased with my acquisition!

Cheers,

Alex.

amulford
12-26-2006, 08:46 AM
If the problem did not follow the tweeter, you are having an issue at the crossover.

Alex, did you check the wire connections at the crossover? There are a products out call DeOxit (http://store.caig.com/s.nl;jsessionid=ac112b1e1f43009bbc4b38a34a01861892 f9be39ce7c.e3eTaxaQbxmTe3uTbhmSa3yNby1ynknvrkLOlQz Np65In0?sc=2&category=188) and DeOxit Gold (http://store.caig.com/s.nl/sc.2/category.292/.f). I'm not sure if you can get it "Down Under", but you may want to treat all of your connections with a similar product. Chances are this has never been done, and given the age of your speakers, some of the connections may have oxidized and perhaps come a little loose. It would be a good idea to go over all of you connections to clean them and make sure they are all nice, snug fits.

bert26
12-26-2006, 10:55 AM
Hey Solid -

So THAT's what Australia looks like? Care to hold the next PolkFest? :p

Congratulations on the purchase - once you get these little things ironed out you will be happy for a very long time!

Welcome to the forums - I may not have anything technical to add to your troubleshooting you can rest easy that guys like Raife and Anthony will help you out.

Cheers!
Chris

DarqueKnight
12-26-2006, 03:06 PM
Is the Adcom a non-common grounded amp? Or is it an inconsitent amp with which to run 2.3 TLs?

I do not know if the GFA-585 is common ground or not. I do know that it is the sterophonic version of the GFA-565 mono block amps, and was described by Adcom as a "dual mono" design. As a dual mono design, the grounds of the left and right channels are most likely not connected together. A continuity check between the negative output terminals with a multimeter would tell for sure.

The negative terminals of the GFA-565 mono amps could be connected together with a wire for a common ground configuration. Since the GFA-585 uses basically the same amplification circuitry as the GFA-565, the GFA-585's grounds could probably be connected together in a similar fashion. Send an email to info@adcom.com to be sure.

solidclub
12-27-2006, 07:19 PM
Hey guys,

Well we seem to have a resolution.

I ran the speakers for a few hours at varying volumes last
night and the "problem" tweeter sang loudly and clearly.

So I guess the answer was that the Adcom was probably
non common-grounded and the PA amp is.

As for the next Polkfest, Ill be glad to have it at my place!

You guys just gotta get yourselves down under, but I'd like
to see you get on a plane with your 1.2TL's and your amps!

Thanks so much!!

Alex.

ps Darqueknight standby for a Compendium order!

Refefer
12-27-2006, 08:04 PM
Mmm, there's nothing like getting a "new" set of speakers, having a problem, and then resolving it. It makes them sound all the more sweeter knowing that they are truly ok and ready to rock.

For the second time, congrats on the pick up!

You'll have to post pics when it's setup to your liking in it's final resting spot!

schwarcw
12-27-2006, 11:28 PM
Glad the problem got solved for you Alex. You may want to use the "Search" tool to find out about mods and upgrades that will make your 2.3TL's sound even better. Darqueknights Compendium has a lot of this information also. Tweeter upgrades are probably the easiest, although it will cost about $400 US. I highly recommend it.

What kind of music are you listening to?

Congrats again and welcome to the Club Polk Forums!

Carl:)

Poee7R
12-28-2006, 08:34 PM
Congrats on the TL's.

Ive just recently bought a pair for a member here and im absolutely in love withem. Even though the top tweeter on the left channel is dead they still sound great.

My wife is from brisbane and it looks like we might be moving there in Sep 07. I wonder if the 2.3's can be considered carry on's. ;)

Dave