Whats better SDA-SRS or SDA2 at 400 watts

ben62670

I was thinking of building the sda-srs speakers. I have most of the drivers for the project. Watching ebay for a long time collecting drivers. The SDA2's have 3 mids, and 2 tweets. The SDA-SRS's have 8 mids, and 4 tweets.
To drive these I have an adcom GFA-585 that puts out 400 per channel at 4 ohms very clean. I think the SDA2's can handle 500 each, and the SDA-SRS can handle 1000 each. Whats the best way to get best sound, and most volume?
Thanks much Ben

Libertyc

Hey Ben:

Not sure what your asking. You want to build SDA SRS from your SDA2s? - or you want to build a set of SDA SRA from scratch? In the long run I think you can buy a set of SRS or 1.2s cheaper than building them yourself. Fire up the SDA2s with the Adcom and they will surprise you.

ben62670

I would not scrap the SDA2's out to make the SDA-SRS clones. I was thinking about driving them with my GFA 555 for rears, and building the SDA-SRS clones for the front. I can't afford an amp more powerful than the 585, so I wasn't sure which would sound better the SDA2's Or SDA-SRS's driven by the GFA-585. I just figured out how to word this better. What sounds better, SDA2's maxed out, or SDA-SRS at half throttle? I could allways use my RTA15tl's as rears if the 585 is insuficient for a large jump in performence from the SDA2's to the clone SDA-SRS.
Thanks again Ben

ben62670

I see you looking F1 master of great Polk Experience, and Knowledge :-)

BobMcG

IMHO: Save your money, time and effort by placing the SDA2s up front and the RT15tls in the rear. Building yourself custom SRSs would be very time consuming and expensive. And you would need to be able to test and take measurements on the custom speakers to see if they are capable of replicating true SRS performance levels or not. The same "look" doesn't mean the same "sound".

Just because you would be running the 1000 watt capable SRSs with a 400 watt amp doesn't necessarily mean you can only run them at "half throttle" and the fairly efficient SDA2s are probably capable of playing louder than you can stand before they are "maxed out".;)

ben62670

Thanks Bob. I have already started the SDA-SRS project for haha's. Driven with an Adcom 555 they have reached 115db at 2 feet very clean c weighted, with peaks to 118db. I think those measurements are kinda optimistic seeing they were taken that close. I don't know what the procedure Polk or anyone else uses for that matter when they rate max db. The cabinets are 6 feet tall. 24 inches x 2 separate chambers for the 4 mw6503's and 2 10 inch pr's. I tried 1 and 2 sl2500's per cabinet they sounded just as good to me with one as they did with 2. The bottom 22 inches house a 12 infinity interlude sub 500 watts they say. I never liked jazz till I built those. I just keep surfing ebay scoring cheap mw's. Not a lot of cost here, a lot of time though. The guys here at this forum have been great. Given me inspiration to build something special that will sound great and last a long time. I am going to completely redo my cabinets, and continue to mess around till I get it right. Then laminate the whole thing in cherry veneer.

Thanks Again Ben

BobMcG

I guess I'm a bit behind on the advice but...

Looks like a nice job!:)

ben62670

Nope I don't think your far behind on advice. I'm jumping right into a big complicated project. I just hope people don't get sick of giving me advice! I have some experience with electronics, but when you add in all the variables that speakers present it can make my head spin! One thing that I am trying to find with no success is data on the different mw drivers. Like impedance at different frequencies mostly. A lot of trial and error to get them where they are now acoustically. Do you have any aspirin, or morphine or something like that lol. I was thinking about getting the woofer testerII. At $150 it might be a worth while investment for me. http://www.woofertester.com/

Again many thanks Ben

BobMcG

I'm trying to figure out a small black object second up from the bottom of the speaker... does it use all active drivers and this is a port?

heiney9

A port with a PR.....WTF?!? How are the lobing issues with tweets side by side and not even time aligned. Same with the MW's how are those aligned? Looks like a phase shift nightmare :eek: :eek:

BobMcG

heiney9 wrote:

A port with a PR.....WTF?!?

That's what I'm wondering about 'cause it kinda, sorta looks that way doesn't it?

ben62670

What you are looking at on the bottom right is an emit K tweeter that was going to have a small chamber with a 5.25 woofer for home theater speakers instead of firing up the whole system. I don't really get what the manufacturers are doing with speaker alignment. IE the tweeter between woofers, tweet above, they all seam to make different claims about speaker placement. These are experimental speakers, this isn't the final design this is just a learning experience. By the way these sound great! sharp fast tight deep bass. Pretty flat response, tweets are a little bright SL2500's. I was thinking about using seas tweets. These speakers sound a lot better than my RTA15tl's, M5's, M4.6's, M10's, infinity RS's, SM's, and reference speakers. Very detailed, and accurate. Nicer sound stage than any of the speakers listed. keep in mind I never built any speakers before these, and I have learned a lot along the way :-)

*edit* heiney9 the tweets are the same arrangement as they are in the SDA2's

Deadof_knight

Ben you go guy, I think what people are missing in your question your not asking wether to build or not, :cool: you are asking for tips on where to go next because you are building. Its rewarding when the project is complete simply because you built them and didnt buy them. You obviously dont have sophisticated test equipment but I belive in a good ear by far. It only sounds good if YOU like it. If you have heard great speakers ( personal opinions vary) and you arre trying to replicate it with you own skill then by all means. Ive built and bought and had a great deal of fun building sub cabinets. I for one had the notion that I could build an sda cabinet myslef or darn close if I ever got the dimensions and so forth, that was before I covinced the wifey that I really wanted them. Course she sorta freaked when I told her how much used speakers were sda 1.2 tls that had been upgraded. The subs Ive built have enterteined me a great deal. Ive rebuilt 2 or the 4 boxes in effort to get the sub sound I wanted I have 12s 10s and 18s ported and unported. The hardest part was cancellations but hard work and dilegence has its rewards. I can rock the house a half mile from me. ( Living in the country has its advantages like volume levels are of no concern to anyone out here )

On another note 400 watts or 1000 watts capable is what you can drive them at in order to be louder by 3 db you have to double your power or double the surface area of the speakers. the more the driver extends the more apt distortion will be come a factor.

ben62670

Thanks much DOK. I do appreciate your post. i feel you get more bass with lots of cone travel, but you do also get more distortion in the mids which does seem to have an adverse affect on overall sound quality. I think i am going to redo the box, and add more speakers. Maybe move one of the PR's to the back like my RTA15tl's. I should prob ally repost this thread to the DIY section instead of the vintage forum. I just ordered the SDA book from DarqueKnight.
Thanks Again Ben