I am sick of my system! A new direction

ben62670

I have looked a Fostex drivers. I had one of those Fat Man tube hybrid/integrated clone amps that would have been perfect for that. I did try a Tang Band 4" full range that just didn't work for me. For now I think I am going to with an SDA type design with modern drivers. When things pick up I will build a nice little tube setup with either Fostex, or Tannoy:cool:

mmadden28

ben62670 wrote: »

I have looked a Fostex drivers. I had one of those Fat Man tube hybrid/integrated clone amps that would have been perfect for that. I did try a Tang Band 4" full range that just didn't work for me. For now I think I am going to with an SDA type design with modern drivers. When things pick up I will build a nice little tube setup with either Fostex, or Tannoy:cool:

I'm tellin ya Ben, as unbeliveable as it sounds, I was really amazed how that little amp actuially made my LSi9s sound pretty good (at low volumes and not that they didn't sound good to begin with)-I wonder what they could do with an eff driver like these Fostex's

ben62670

Well I am thinking I want to finish these nicely. I hate doing the finishing part. 44" cabs didn't sound as big as it is. I designed the cabs around the drivers, and started looking at them. These things are nearly identical to 1C's. These are a half inch taller. I was shooting for a cab that wouldn't need stand. I have some 12 PR's from 1C's that I may just drop in. I was going to go with dual 3" ports on the bottom, but with the cabs being the same volume as 1C's I may just drop the PR's in. The FS is within a few hz.

Early B.

Ben --

Stay away from sharp objects for a while. Geez.

ben62670

No blood so far, and there was none on your's:)

Face

Nice Monkey Coffins.

Face

ben62670 wrote: »

No blood so far, and there was none on your's:)

Pffff...what happened to blood adding character?

ben62670

Face wrote: »

Pffff...what happened to blood adding character?

If I want blood(and puss) I can just squeeze the hole in the palm of my hand I got from modding some terminal cups with a drill;)

Edit: I need a work bench.

beardog03

dude !
You crack me up !!

megasat16

Good! Get a proper workbench or build one already! You need it, bro!

Now, you are tired of your Giant SDA. What you gonna do with it since you seems addicted to the baby version of it? After I got a pair of Platinum Amazing, I could use a pair of SDA to play along side by side.

ben62670

It's not so much that I am tired off the big ones. I am tired of trying to make them work in too small of an environment. I was thinking about bringing them out on the deck at our get together this spring, blast out the neighborhood with some nice music, and finish with some Primus. After that we could remove the drivers, give them a shove off the 14 foot high deck, and set them on fire. I have changed my mind, and I will instead rip out some walls in the basement, and make a large HT room:cool:

ben62670

I can't edit post 34:( I did some calcs with the MW woofers, and I can not recommend using the PR's with Silver Flute drivers!

Face

Helper woofer.

Systems

ben62670 wrote: »

I can't edit post 34:( I did some calcs with the MW woofers, and I can not recommend using the PR's with Silver Flute drivers!

Can you get the T/S parameters for the MW's?If the Fs,Vas and Qtc of the SF's are reasonably similar to the MW's then you should be OK using the PR.


Nice lookin cab so far.

ben62670

GV#27 wrote: »

Can you get the T/S parameters for the MW's?If the Fs,Vas and Qtc of the SF's are reasonably similar to the MW's then you should be OK using the PR.


Nice lookin cab so far.

I have them. The MW line likes real big boxes when ported. Without the specs on the PR I would not be able to tun it properly. Also I can never get WINisd to calculated a box properly with a PR even if I had the specs. Each array is in its own chamber, and is going to be ported with its own port. The stereo, and dim drivers require different volume boxes. Both ports will be 3"ers.

Face

The 4 5.5's have the area of a single 12, but won't dig quite as deep. They will run down to 40 with a 3db drop. Add room gain and I am plenty happy for tunes. With SDA's the helper woofer would need another amp to be driven. It would make the XO complicated, and inefficient to add it to the speaker passive XOed. I am going active for now till I figure where I want the XO point to be.

Edit: The VAS, and the Qts are much higher in the Polks.

Systems

ben62670 wrote: »

The stereo, and dim drivers require different volume boxes.

Ah because you are using both 4 ohm and 8 ohm versions thus different T/S par's ?

Both ports will be 3"ers.

Good choice to keep port noise low.

The 4 5.5's have the area of a single 12, but won't dig quite as deep.

To eliminate the potential for bass cancelation you will need to hi pass filter(big series cap) the dim drivers in the 100-200hz range ,correct?Then feed the stereo sections bass to the dims via a large coil.

ben62670

The two different drivers require a box of 1.1cf for one array, and 2.1cf for the other.

The port should be about 7" on both arrays;)

Actually the SDA inductor allows the bass to go through, and passes the stereo cancellation frequencies to the opposing channel.

Systems

ben62670 wrote: »

The two different drivers require a box of 1.1cf for one array, and 2.1cf for the other.

Wow the differences in their Vas must substantial.

Actually the SDA inductor allows the bass to go through

Yes it feeds the in phase bass to the dim's from the stereo array,but at the same time the dims will still be recieving the out of phase(R-L) bass.The schem for the 1B is shows what I,m getting at.The 55uf cap in series with the DA filters the out of phase bass then the 9.6mh coil feeds in the stereo bass after the cap.Strangely Polk did'nt see the need to filter the DA on other iterations.

ben62670

You must be looking at the older blade blade connected SDA's. On the pin blade the inductor is after the the dim speakers and between the amp. Take a look at a any pin/blade setup. The speakers have an inductor in each cab before the amp ground after the speaker in the dim arrays. Look at the 1C's being they are the most similar to mine.
Ben

ben62670

Face

Except for the mid/woofers being on the small side...not bad.

So how are you going to finish them?

Most importantly, how do they sound?

ben62670

I was thinking some furniture grade 1/4" oak veneered plywood. I have the Vifa tweeter in there, and if it wasn't an active XO I don't know if it could keep up. The ports are some pieces of scrap 3" PVC till my flared ports get here. The holes are already cut to size. I am playing with the XO point. Madisound says 2500 or so:rolleyes: I am running them full range right now with no problems. They do actually roll of rather nice(5k). I may play with my car audio XO just to tweak it. Bass is better than you would think for 4 5.5's. 4 5.5's equals one 12" so it's not like there is not enough displacement. It is tuned to 40hz(-3db). I played some familiar bass heavy songs, and it does very nice. Not 123db like the big ones, but handles music just fine. Kick drums have a very tight hit. I don't have too much time on them so I am not going to comment too much. I have to get back to work. No time to play:(
Ben

tonyb

Ben.for Christmas,ask Santa for a girlfriend,you have way too much time on your hands.:p


Lookin' good though:)

ben62670

tonyb wrote: »

Ben.for Christmas,ask Santa for a girlfriend,you have way too much time on your hands.:p


Lookin' good though:)

I can shut my tunes down when I want to:)

Actually it only takes about 2 hours to build the cabs. I have all the tools to pump them out fairly quick;)

tonyb

Just yankin' your chain,Ben.Though you do outstanding work,you need to get out and about alittle more pal.Merry Christmas to you and the girls.

ben62670

Well I got rid of the nippled Vifa's. They were too directional for an SDA type of design. I found myself raising the amp on the highs to get the sizzle I wanted. It was back and for with the control. Too much helped the higher end, but made the mids to forward.
I ended up going with these. They are much better off axis than the ring radiators.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=264-578
The ring radiators are fine on speakers you toe in but don't work well with SDA's. There is another ring radiator that is better off axis than the ring I chose, but not as good as this dome. I know GV I should have listened to you from the get go. Guys are drawn to nipples. What can I say:o

nooshinjohn

any chance of getting one of the baby sda for a surround channel?

ben62670

Na. I did those just to have the smallest SDA's. I am pulling the drivers for an in-wall surround project. I will rebuild them later for the bedroom;)

organ

Awesome stuff. Nice set up. Keep us posted on the project. With DIY, I bet you could build somthing huge that can surpass the SRT. I seriously need to get my ears on a pair of SDA one day.

ben62670

Well I have added the passives in the cabs, and running the new DIY DAC. I used to want the biggest baddest. I am now enjoying nice details, and sound stage like never before. Bass is shy on the very lowest end, but everything else is just coming in. I am going 2.3 style with the SDA's, modding the amps, and DAC soon. For what I have to work with I am so very pleased. I am listening to a Tel-Arc CD sampler. It's a beautiful thing:)