RT 12 Speakers Rebuild

fatpiggy

Importing a set of LSi15's would cost me around $2135 US plus import tax of around 5%.Which works out to a saving of around $1100 US for the pair.Even if I didnt get warranty by importing I would still be better off ,$1100 US would buy a new set of drivers and crossovers worse case situation.You would have to be very unlucky to need warranty on a set of Polk speakers.Every set I have owned have been rock solid.If you dont overload them and not be stupid by using the wrong amp, they should last a life time. $3,299.00 for a pair of LSi15"s is way too much for most people.When you consider you also will need a centre and a couple of rears for a basic home theater set up.

Fat Piggy

fatpiggy

Greyford,
The reason why I ask what driver as I see parts express have a special on a Peerless XLS 12" for $139 which includes free shipping for you guys.The XLS Peerless is a nice driver might be worth having alook at.You will need to run its specs through WinSD to see if it will fit your table size but I think it has a small VAS 4.91 cu/ft 12mm excursion frequency range from 19hz to 500hz.Great price if you can make it fit the space.You might even have some cash left over to buy one of those precision flaired ports they sell.

Fat Piggy

cheif pontiac

I'll ship you monitor 10's for a grand whenever you want! let me know! LOL

You did buy the Trilaminate tweeters right? I've thought of putting some Tri's in my RT12's I have a set of RT7's I am not using right now. I was thinking of swapping the tweeters in the two sets.

fatpiggy

Hi Cheif,
Thanks for the offer but I dont have that kind of cash to spend on another set on Polk at the moment.If I did have the cash I would go for a new pair of LSi's , but like I said I can only dream.I will get my RT 12's going and save up to buy another amp.

Yes I am changing the tweeters in the RT12's to SL6001 tweeters, they are Tri Lamanites, I have also purchased a pair of SL 5001 tweeters they are silk domes.The original tweeters in the RT 12's wee SL 5501's also silk domes.

Heres some spec information I have on these tweeters if your intrested.I think the SL 6001's are probally the best tweeters to use.

Polk Audio 6.5" Woofer - Audiophile Quality
Polk Part number MW 7010

Specifications

Size / Type = 6.50" Dynamic Balance®
SPL = 90 db @ 1w/1m Wattage = 125 Watts RMS / 250 Watts Peak
Polymer cone woofer, rubber surround
Response = 40 Hz. to 10 kHz.
Weight = Right a 4 pound ea.
Magnet = Shielded VC = 1" ( 25 mm)

Ohms = 8 ohms

TS Measurements

f(s) - 40 Hz.
Q(ms) - 3.821
V(as) - 7.62 liters ( 0.269 cf. )
n(0) - 0.05%
M(ms) - 55.89 grams
R(e) - 0.62 Ohms
Q(es) - 0.870
SPL - 90 dB @ 1W/1m
C(ms) - 0.28 mm/N
Z(max) - 3.36 Ohms
Q(ts) - 0.709
L(e) - 0.07 mH


New version Tweeter SL6001 Tri Lamanite Dome

Specifications

* Size / Type = 3.75" Tweeter Dynamic Balance® Trilaminate Dome
* SPL = 91 db @ 1w/1m
* Wattage = 45 Watts RMS / 90 Watts Peak
* TriLaminte Dome Tweeter
* Response = 1600 Hz. to 25 kHz.
* Weight = 1 pound ea.
* Magnet = Un-Shielded
* VC = 1"
* Ohms = 8 ohms
* Markings both the SL6001 and BD0113-A part numbers are on the tweeter.

---

RT 12 SL5501 orignal tweeter

* Size / Type = 3.750" Dynamic Balance® polymer dome tweeter
* SPL = 90 db @ 1w/1m
* Wattage = 45 Watts RMS / 90 Watts Peak
* Polymer dome tweeter
* Response = 2.5 kHz. to 20 kHz.
* Weight = 1 pound ea.
* Magnet = Shielded
* VC = 1" ( 25 mm)
* Ohms = 8 ohms



RT 12 First original tweeter SL5001

Specifications

* Size / Type = 3.750" Dynamic Balance® poly dome tweeter
* SPL = 92 db @ 1w/1m
* Wattage = 40 Watts RMS / 80 Watts Peak
* Polymer dome tweeter
* Response = 1.5 kHz. to 21 kHz.
* Weight = 1 pound ea.
* Magnet = UnShielded
* VC = 1" ( 25 mm)
* Ohms = 8 ohms

fatpiggy

I also believe you dont need to change the crossover capacitor for any of these tweeters all should work fine and be a direct replacement.Im going to do a few mods upgrades to my crossovers lat some point later on.

Fatpiggy

ben62670

BASH amps suck.

fatpiggy

Ben,
Bash amps suck what, the cash out of your pocket, excessive power out of the grid....Kind of an opened end statement dont your think.

Id say more than 50% of the amps in subs these days use bash amps, thier cheap and do the job.Its only for a sub.

If you really wanted to get crazy you could spend $500 on a nice mono amp and build a passive sub.But where do you draw the line.A $100 amp or a $500 amp.

Fatpiggy

ben62670

I have worked on plety of bash amps. They suck. You can get better for the same coin. I had a $1000 Infinity sub with a bash amp. It died too. Kinda embarrassing for a top of the line model to die like that. The output chips are over stressed and the PS is weak. Look at Dayton plates for a reliable amp.
http://www.parts-express.com/wizards/searchResults.cfm?srchExt=CAT&srchCat=505
Not trying to come off as a smart a$$, but I have opened a few of the dead ones up. Sub par parts and design.
Ben

[Deleted User]

In the years I got to work with the BASH amp guys, I found their amps to have a high level of quality. Let's face it electronics fail in anybody's product.
The BASH designs incorporate numerous protection schemes and it is up to the customer (i.e. - Polk, Infinity, et al) to select the protection thresholds they are confortable with. Their amps do a really go job of producing lots of power and being energy efficient. :cool:

ben62670

Take apart a BASH amp and take apart a Dayton of equal power. You'll see what I mean. The transformer in a 1000 watt BASH is dinky. The caps are tiny, and there are very few output devices(transistors). I'll pass.

fatpiggy

I agree with Nap, The Bash Design is Good..Its built for a price and does a good job.If you can find an amp that does the same job for size , and price go for it.Gone are the days of well built units..is mass production for a profit, you pay for what you get.

I dont think you will find a Dayton 300w amp plate you have to get a 500w Dayton price listed $299, or get a 240w for $99.The Dayton amp plates are huge in size compared to the Bash amp plate.


Fatpiggy

greyford1979

Make any more progress on the speakers? Anxious to see how that cedar looks lol

fatpiggy

Hello Greyford,
I have been a bit busy with work on the cattle this last week,preg testing and branding,castrating steers that time of year,you must be psychic,Hows your second sub build going.Got some good news for you.

I just got back from my friends woodshop today.The cabinets turned out better than I thought.I have just got in the door from unloading some very heavy speakers from the back of the car.I have got the camera on charge and will take some pictures.Will try and post some pics today.

I have still to work out the grills, as the original were badly designed and covered half the tweeter, really dumb.So I will be designing new grills to suit the new cabinets.Will need to scratch my head and work out how I want them to look.The old grill are rubbish and wont fit the new cabinets now they have been modified.

I got the top cut off the cabinets and got rid of the stupid rounded tops.Both cabinets now sport square tops.The front panel has been laminated with black gloss veener looks very smart.Im glad my friend talked me into all Cedar sides and only glossing the front.

My friend got all the holes cut out exact and glued the black veener perfect, an amazing job.I just have to remove some residual glue and make a few adjustments to the speaker cutouts.

Both the cabinets are now an extra 20 mm - 3/4 inch thicker all panels have been dowel and glued no nails used in the make over.The cabinets are now around 38mm - 1 1/2 thick just the front panel is 19mm.

I had to get 2 new pedestals made up as the older pedestials were too small due to the extra thickness of the cabinets.They look great all in Cedar.

I just have to epoxy repair some loose pedestial mounting nuts in the cabinets and I can fit the pedestials to the bottom of the cabinets with the old sound cones.


Still waiting for my new woofers to turn up should be here this week sometime.

Still waiting for some new crossover capacitors to turn up.Wont get them for a few weeks.

At least the hard part ( cabinets) has been completed.Over the next few weeks I will get into town and get some high grade sound dead sponge I found in a specialty store and start on the inside of the top half of the cabinets.I was thinking of adding an extra braces and replacing the port tubes but I think I will leave it original and just see how they sound as is.

I think the upgrades on the crossovers should vastly improve the sound but time will tell.


Fatpiggy

fatpiggy

Heres some pictures for you all...My rebuilt RT 12's are going to look nice..

Fatpiggy

fatpiggy

And a couple more...

Fatpiggy

Outfitter03

Man those look sweet. Talk about a nice damping upgrade doweling that extra thickness on!

Have been reading your progress and I greatly enjoy this thread. Take pictures of the damping sponge and hope you receive your other parts soon. Again nice work!

[Deleted User]

Man, very nice. I can't wait until they are done. :cool:

PrazVT

Indeed - very pretty finish on those speakers fatpiggy. I like the wood color.

mmadden28

Very nice! They look gorgeous!! Keep up the good work.


By the way, for kicks and giggles I did a quick online calc with DHL on what it would cost to ship something like a pair of LSi9's to you, and the shipping cost alone (including duties and ins.) was about $2300!!! Simply wow. Even more shocking was that they would be there in as little as week--takes over a week for me to get a simple package of prescription meds from Philly (about 30 miles away) to me via USPS standard snail mail.

mmadden28

Are those veneered original foot plates or did you just have new ones crafted?

fatpiggy

Thanks for the positive comments guys.

I was very surprized to see how the cabinets turned out when I went to pick them up yesterday.They looked even better when I got them home and gave them a dust. The finish has been spray lacquered.

Im more than happy with the results.I could not have done this job myself.

The pedestal plates are new made out of solid Cedar, I had my friend make up some new plates to match the cabinets,they are about 1 inch larger he swapped over the screw inserts for the pedestal rubber feet and cut out a recess to house the sound cones.I will install the new pedestals after I do a few more mods.

I put the old speakers in just to see if they fit and they need a bit of cleaning up around the mounting holes.They look unreal with the drivers in place and weigh a ton maybe 50 pounds each with the drivers installed.

Fatpiggy

fatpiggy

Heres a picture with the old drivers sitting in the holes to give you a better idea what they will look like completed. The floor sound coupling as Polk call in still needs to be installed so the final height will be taller once those feet nave been fitted.I have not changed the original height. The only changes have been to the width and depth.

Fatpiggy

fatpiggy

mmadden28,
Heres a better shot of the foot plates.You can see the old foot plate made of MDF beside the new ones.The new foot plates have the old cones fitted.

Fatpiggy

dorokusai

They're looking good and should sound better than before based on your new drivers and cabinet tweaks.

jimsvm

Things are looking awesome. Thanks for the heads up on the drivers. Love those base plates.

greyford1979

Wow man they are looking beautiful!! Love the look of the cedar:eek::biggrin:

fatpiggy

Hi Greyford,
Yes they came up very smart...My woofers turned up this morning.3 of them look secondhand as they have marks on the sides of the cones.Looks like a grill has pressed marks into the surrounds.Could be the cardboard packaging rubbing the cones during transport, not sure.

I have been cleaning up the speaker holes.Got one enclosure finished and a set of drivers installed.I mounted one of the feet to see how it all looks.My friend didnt extend the feet to the rear so they are a bit short at the rear, but it still looks ok.I was hopeing the foot would line up with the back of the enclosure.

The tree locks I ordered for the grill are the wrong size.Polk sent out 7/16 inch hole size treeloks and not 3/8 inch hole which is the correct size.They are too large and look stupid.

They gave me a part number to order and the number is wrong or the part is wrong.Im really pissed as this is the 3 rd set of treeloks I have ordered from various suppliers and none can sup[ply the right size.

Anybody got 12 3/8 inch hole grill treelok clips they can sell me I need 12.

Fatpiggy

dorokusai

fatpiggy wrote: »

Hi Greyford,
Yes they came up very smart...My woofers turned up this morning.3 of them look secondhand as they have marks on the sides of the cones.Looks like a grill has pressed marks into the surrounds.Could be the cardboard packaging rubbing the cones during transport, not sure.

I have been cleaning up the speaker holes.Got one enclosure finished and a set of drivers installed.I mounted one of the feet to see how it all looks.My friend didnt extend the feet to the rear so they are a bit short at the rear, but it still looks ok.I was hopeing the foot would line up with the back of the enclosure.

The tree locks I ordered for the grill are the wrong size.Polk sent out 7/16 inch hole size treeloks and not 3/8 inch hole which is the correct size.They are too large and look stupid.

They gave me a part number to order and the number is wrong or the part is wrong.Im really pissed as this is the 3 rd set of treeloks I have ordered from various suppliers and none can sup[ply the right size.

Anybody got 12 3/8 inch hole grill treelok clips they can sell me I need 12.

Fatpiggy

One, remember that those treelocks haven't been carried by Polk for almost 20 years and when they finally found a suitable replacement, they weren't perfect. If you find any other manufacturers that would care that much let me know.

Since you ordered new woofers, you received new woofers and the packaging is really tight on them. You should post some pictures if you find that it's an issue.

If you email/PM your shipping addy I'll send you some of the smaller ones but again, they may not be perfect. They are the smaller ones. I'll cover the cost of the postage and clips, just pay it forward down the road.

What part numbers were you given by Polk? Please list them.

fatpiggy

dorokusai,
Part number for the treeloks quoted from customer service, Regular Treeloks (RF9905-1) (Speaker Grille Clips)

I will post some pictures of the new woofers for you to look at and you can tell me what you think.

Fatpiggy

fatpiggy

Part number for the woofers BD0719-W Driver MW7010