Amp for SDAII and 5B's

Rookie

I just picked up a nice pair of original SDAII's [with no interconnect cable] and a pair of 5B's. [bought both pair for $225] I took them to my Brother in law's for a demo because I have yet to get my receiver or amp for them, I lucked out because he has a set of SDA2b's and is not using his interconnect cable. He's has his set of SDA2B's powered with 2 bridged Adcom GFA555II's [polk cautions you not to run the inter. cable in this power configuration]. I hooked both my SDAII's and 5b's up to his bridged Adcom's and they sounded good very big and detailed. My question is do I really need to run 2 amps to get the best out of them or what receiver or amp do you SDA guru's suggest, also is it a bad match to 2 channel both the SDAII's and 5b's together, it looks as though SDA and 5b's share tweeters and maybe a driver? I've always owned Klipsch heritage in the past and have no experience with Polk. Thanks for any help. Can I order a interconnect cable from polk? any other suggestions where to get one.

erniejade

I am not sure but i thought you would run into issues running them in bridge with the IC?

and No you dont need to run both to get the best sound out of them.


Some people liek to run them in a bi amp config where one amp is running the highs and one the lows but, many feel there is not much benifit from this.

Rookie

Your right Polk warns you not to run the cable in bridge. I was only going to run the cable with a single power source. If I run the cable with the sda's and the 5b's am I messing up the array?


I have a old pioneer SX 3900 that need a little TLC is it worth fixing up and running it with the SDAII's, or should I go another route.

dcoil

Hi Rookie and welcome! I'm rather new here also, but I've got 2 pair of SDA's (SRS and 2B's). The one thing that I like the most out of these is the incredible imaging from the SDA. But without the interconnect, you are not hearing ANY of the SDA technology. Look over in the forum for 'Vintage Speakers'. There is so much info on the SDA's you could read the archives of this for weeks, and learn something new in most every thread. They do need to have some good power (200w per channel of high current capable amplification) - this is stated over and over again. To get the best sound out of them do not scrimp on the amp. I'm not there yet (HT amp of only 125W, but this is next on my list. But only a few are bi-amping. The amp does need to be a common ground amp, and if not you need the AI-1 interface. This will not work on all SDA speakers (will not work on the early ones, I don't know about your SDAII's). If you take only 1 piece of advise from me, USE THE INTERCONNECT. If you like these speakers now your in for quit a surprise. Also, make sure you have them setup correctly. There is a proper distance between speakers, and from the speaker line to the listener, don't toe in, etc. And if you can't find an interconnect, you can always change the connector on the speaker and make one (several good articles on this in the Vintage forum).

Rookie

Thanks for thr reply decoil.

My brother in law is letting me use his interconnect cable because his set of SDA2b's is powerd by bridged GFA555 adcom's.

My Polk dealer told me I can still order the interconnect cable from polk for $50.00

Right now my SDAII's are hooked up to a vintage pioneer SX3900 recevier 120wpc. Question: with the interconnect cable installed should all four tweeters be working? I have two SL-1000 tweeters in each speaker. The tweeters are dated Nov 1984 so I think I have first generation SDAII's, please correct me if I'm wrong.

Earlier I put my 5b's on top of the SDAII's and demoed them together with two bridged adcom 555's and they sounded great! As a novice is this a no no to have two sets of speakers running together one on top of the other?

tonyb

Rookie wrote: »

Earlier I put my 5b's on top of the SDAII's and demoed them together with two bridged adcom 555's and they sounded great! As a novice is this a no no to have two sets of speakers running together one on top of the other?

In short...YES.

comfortablycurt

Don't fall under the illusion that you need to have a 200wpc minimum to effectively drive your speakers. I run my SDA 2A's and my Monitor 7A's with a 100wpc Adcom GFA-545, and it can drive them with PLENTY of authority, and sound absolutely fantastic while doing it. Higher powered amps do have their merits...but it's by no means a necessity. Don't scrimp on the QUALITY of the amp in the name of getting a higher wattage rating.

My measly little 100 watt amp can drive my SDA's to levels for louder than I ever care to listen at. I think half the problem is that many people tend to listen to their music at levels that are way too high. Personally, I value my sense of hearing and would like to keep it for the rest of my life so I can continue to enjoy this hobby. All of you guys that are cranking your speakers to 115-120db are going to be going deaf while I'm sitting here with my perfect sense of hearing. My 545 can easily drive my SDA's to 95-100db without breaking a sweat, and when pushed it can get them up to about 110db average.

If you're not familiar with how db's correlate to real life...95-100db is LOUD. Louder, in fact, than I do most of my listening at. When I'm doing some critical listening, it tends to be more in the 75-90db range, and that's by no means quiet.

Rookie

Curt, Are you driving both your SDAII's and 7A's at the same time and if so are you using the the interconnect cable?

I bought my first new system in 1992 a GTP-555II preamp tuner, GFA-545II amp they powerd my Klipsch Forte2's, some told me it was the wrong amp for those speakers but I thought it sounded good very clear and low end punch with the amp cranked would smack you in the chest. I found a cheap pair LaScala's a few years later and hooked them up to the same power and it didn't have quit the same feel.

I was looking to replace my pair of Klipsch forte's2's that I sold a few years back but stumbled upon these SDAII's and 5b's for $225 and thought it was a deal.... I hope this was a good choice as I had no idea that the first genetation SDAII's [extra tweeter] do not get good press from the the posts that I have read.

Question: Should I keep the vintage Pioneer sx3900, spend some money and have it tuned up? or would an Adcom be the better way to go. I'm looking around at used and my budget is $400-$500.