Dreadnaught Avel-Lindberg 1000VA Transformer Group Buy?

nspindel wrote: »

All set. Just waiting to hear from Inthefade.

I was thinking about getting 2 of these, was hoping we could get to 25. I really don't need to spend that much though.

Can't wait to hear the difference.

I'll take your good advice Larry. When the time comes I'd like my case with the Speakon terminals

Larry, I'm in for one case w/speakon cutouts. Thanks

I strongly encourage everyone to take advantage of this run of cases Larry is doing. The transformer is not meant to sit on it's own, it's meant to be mounted in a case, and Larry's is custom designed for this exact task, his craftsmanship is incredible.

I also encourage the use of speakons!

Larry, can you whip me up a speakon backplate when you do these?

I would like a case with speakons please.

This thread has over 2700 views, and only 12 units are being ordered? Really??

case w/speakon's please!

nspindel please let me know what I need to do.

nspindel wrote: »

Ah we have another! 2 more needed and everyone saves some money! South Dakota Po, I will send you a pm.

This is great, sure wish we could get to 25¡¡!

Hi scubaste4sq, yes there is still time to get in. I will PM you.

At this point, I have received payment for 12 units:

Inthefade, you're supposed to be paying me today, correct? That will make 13.

I sent a PM to South Dakota Po already, have not heard back or received payment. If he is in, that will be 14.

When scubasteve4sq pays, we'll be at 15.

Once I receive payment for 15 units, I will turn around and refund everyone the difference, which will be $26.74.

I will be placing the order on Monday so payment by Sunday is required for you to be in, although I still need to check with Melanie if we can add to this order later on.

I thought it might be useful in the interests of drumming up more participants to put up a good post explaining what this group buy is all about, with a few links to some highly useful threads.

The original SDA design worked only with common ground amps. Some non-common ground amps allow you to strap the negative poles together, essentially making it a common ground amp, without a problem. Others do not, and very very bad things can happen if you do. You certainly couldn't use mono blocks with SDA's. Polk's later design iteration of the SDA's allowed for the use of a new cable they sold called the AI-1. You can still find them for sale on occasion on eBay or they come up here every now and then. The AI-1 allowed the SDA signal to pass between the speakers without requiring the grounds to connect by using an isolation transformer. However, like other parts of the crossover design, this cable was manufactured to meet a price point by using less expensive (i.e. inferior) components. It worked, and allowed you to use SDA's with non-common ground amps, but it didn't sound as good as using a straight cable.

Enter DarqueKnight and his research into using much better isolation transformers. His original intention was to replace the original AI-1 he needed in a scenario where he was not using a common ground amp. He researched several different transformers and settled in on an 800VA transformer from Avel Lindberg for his original Dread:

http://www.polkaudio.com/forums/showthread.php?73304-AI-1-Dreadnought-Preliminary-Results
http://www.polkaudio.com/forums/showthread.php?74472-The-AI-1-Dreadnought-Project-Pt.1

DK later discovered that improvements continued using an even bigger 1000VA transformer from AL, however these were not a stock part and required a minimum purchase of 10 units, hence these group buys:

http://www.polkaudio.com/forums/showthread.php?131537-Plitron-1000VA-Transformer-Evaluation
http://www.polkaudio.com/forums/showthread.php?129829-The-AI-1-Dreadnought-Project-Pt.2-Upgrade-to-1000VA-Transformer

Somewhere along the line, he experimented with the Dread using a common ground amp, and discovered that when built with a boutique audio grade transformer like we're ordering here, the original AI-1 design actually sounds considerable better than a straight SDA connection when used with a common ground amp as well. That's when a lot of interest in these transformers came about, a lot of people including myself are using a Dreadnaught (either 1000VA or 800VA) with common ground amps and are loving the results.

So this group buy is for the transformer. Sounds expensive for a transformer, but this thing is a massive hunk of audio grade copper. You'll need a case to mount it in. Save yourself time and get Larry's. You'll need to consider what kind of connectors you'll need. Save yourself time and get Speakons:

http://www.polkaudio.com/forums/showthread.php?142058-A-slightly-different-take-on-the-Dreadnought

Finally, you'll need to consider cables, and how they terminate on the speaker side. Personally, I replaced my pin-blade SDA connector with a Speakon and haven't looked back. You can also use a single binding post, connect the positive Dreadnaught cable, and connect the negative to the same negative post that you connect the negative speaker cable coming from the amp. Helps to use both a spade and a banana on the same terminal. I'd recommend going Speakon though!

Hopefully I'll get paid three times today and we'll be at 15 paid units. Then we try to recruit 5 more over the weekend and get to 20!

Kudos to Neil & Larry and everyone making this happen!!

I joined in knowing I may never find some SDA's to use this with, but if I did.....I didn't want to try and find this stuff later, plus Larry making the cases. and maybe making his famous rings, this is a good time to be a Polkie

South Dakota Po and scubasteve4sq I need to hear from you.