SDA2A's and Amplification

renowilliams

I just picked up some great SDA2A's today and I'm looking for input regarding amplification.

I was thinking of using my Pioneer Elite VSX-49 TXi as a pre-amp and getting a Rotel RB-1070. What are your thoughts on this combonation? Any other suggestions amplifier wise.

chandler9a

whats your budget? There a lot of choices out there but it depends on your preference and how much you want to spend.

I believe the Rotel you suggested is pretty decent.

renowilliams

I've heard Rotel is pretty good, I found one with original box not too far away. If the guy who came to see my RTiA5's buys them,I may pick it up.

I also if anyone knows if you can identify the difference between 2A and 2B's with the serial number??


I'm still not sure which ones I have

On3s&Z3r0s

Doing it by serial number would be tricky, if at all possible. Did they end up having the blade/blade interconnect? If so, the most reliable way to tell what they are would be to unscrew one of the mid-woofers and see what it is. A MW6510 would mean they are SDA 2A's, a different MW would mean 2B's.

This thread contains links to the schematics for the various SDA models, and if you scroll down to the bottom there is a PDF that lists the drivers, etc. used to build the various models.

http://www.polkaudio.com/forums/showthread.php?t=55888

renowilliams

Ok Thanks,I checked they are definatley 2A's. I figured as they have serial numers starting with 1

renowilliams

Now the big decision for me is what amp to get. I just found a NAD C275 BEE amp not too far away, any thoughts on this amp anyone??

On3s&Z3r0s

I haven't used that particular amp, but I use mostly NAD gear. I like NAD's sound a lot with my SDA's. My opinion (and I know it might draw some fire) is that the sound of some of the other mid-market brands like Adcom and Rotel can vary quite a bit by model. NAD seems pretty consistent as far as their sound goes. Build quality with the NAD's can be iffy, but those BEE's are reputedly pretty well built. Honestly, 150 NAD watts is a bundle of power for those speakers. Wouldn't hurt, but you probably don't need that much.

Joe08867

I would say if you could try it you would be better off. NAD has it's own sound as well as Adcom, Rotel, B&K and others.

NAD is very sterile to me but are also very true to the original recording. This can be good and also be very tough on poorly recorded music (ie, MP3's) Adcom can be a little thin on the bottom unless it is one of there bigger models, Rotel and B&K would be my personal choices. B&K being warmer than Rotel but Rotel being very stable.

Again this is all my personal opinion of what I have used. Others may have different opinions on this.

renowilliams

Well, I found a Rotel RB870BX close for a real good deal so I'm going to get it and see. It might be a little weak power wise as it is 200 watts per channel into 4 ohms but I hear Rotel amps are good for headroom.

inspiredsports

I've used my NAD 7600 Receiver and NAD 2600A amp with 1700 preamp to power SDA 2B's since 1987 (the 7600 integrated the 2600A, 1700 preamp and 4300 tuner into a single unit so the sound of the 2 rigs is identical). These are amongst the most musical solid state amps I've heard. I've recently had both professionally rebuilt. They are still in use every day, and will be passed down to my son.

I believe the C275 BEE was the "next generation" 2600A with nearly identical circuitry and sound quality and some improvements to the power supply circuitry.

These amps are robust enough to even power SRS's, and will never break a sweat with 2A's or B's when drawn down into a 4 or 6 ohm load.

The Rotel is quite good also, but the NAD is the more powerful of the two by a fairly wide margin.

A quick comparison related directly to current draw / power supply potential is the NAD you are considering weighs in at 32 lbs, and the Rotel at 21.

cnh

If you're going to use the Pioneer as a pre then that will have some effect on what a power amp connected to it will sound like? The Rotel has plenty of power for a set of 2As--they are fairly efficient.

I own a NAD integrated and I agree that it is somewhat 'unforgiving' of poor recordings. So far I have yet to hear the 'warmish' sound these NADs are supposed to have. With a mid-fi CDP the NAD can sound a little harsh and that includes running my LSI-7s on it? Which 'surprised' me? Maybe there is something wrong with my unit? In any case the NAD integrated suggested has MORE than enough power for SDA 2As.

Do your 2As have original SL2000 tweeters in them? Because that will be a problem. Probably the only way to 'tame' those is with TUBES! Tube amps. Or get the replacement RDOs.

I'd say if you like the Pioneer sound the Rotel should be OK with it...although that is a pretty OLD unit, if I'm not mistaken?

cnh

inspiredsports

cnh wrote: »

If you're going to use the Pioneer as a pre then that will have some effect on what a power amp connected to it will sound like? The Rotel has plenty of power for a set of 2As--they are fairly efficient.

I own a NAD integrated and I agree that it is somewhat 'unforgiving' of poor recordings. So far I have yet to hear the 'warmish' sound these NADs are supposed to have. With a mid-fi CDP the NAD can sound a little harsh and that includes running my LSI-7s on it? Which 'surprised' me? Maybe there is something wrong with my unit? In any case the NAD integrated suggested has MORE than enough power for SDA 2As.

Do your 2As have original SL2000 tweeters in them? Because that will be a problem. Probably the only way to 'tame' those is with TUBES! Tube amps. Or get the replacement RDOs.

I'd say if you like the Pioneer sound the Rotel should be OK with it...although that is a pretty OLD unit, if I'm not mistaken?

cnh

I'm a bit curious how you determined, "with a mid-fi CDP the NAD can sound harsh" . . . ???

I've connected many various quality CDP's to both of my NAD rigs, and to my tube rig. When I connected harsh sounding CDP's, the CDP's sounded harsh. When I connected smoother sounding CDP's, the CDP's sounded smoother.

The amps consistently did their jobs, ie.: reproducing what was fed into them. You know the old saying . . . "Garbage in, Garbage out".


Versus a wide spectrum of other amps, NAD's are a bit less clinical and a just tad bit more on the "warm" or "musical" side, and they are brutally powerful for their stated WRMS outputs.

I'd sure also like to know what specific tubes you recommend we use to tame those strident SL2000's? Tubes that "filter out" 12.5 to 13.5 kHz I presume? Does Bose make those; "13kHz Canceling Tubes"? :biggrin:

cnh

It might just be my NAD. I know some of their amps have reliability problems? So I'm not really disagreeing with you. I've used a Harman Kardon HD990 with the NAD--a decent upsampling CDP--with LSI-7s and they were too 'bright' for my ears on many Redbook CDs. Just telling it as I hear it...no foul meant.

As for 13Khz, you know I can barely hear that high....they call it 'age'? So maybe it's not the tubes but my aging eardrums? If I can hear to 14K it's a GOOD day! You know...it's how most people over 40 can't hear the high end anymore (much over 14 or 15K) and less than that if they've attended too many Rock Concerts in their youth.

I should add that my ears, as declining as they are, detect any harshness in 'digital' sound and are disturbed by it. When I say 'warm' I mean REALLY warm not just a hint of it. Which is one reason I am seriously considering a tube stage CDP.

I'm open to the NAD sound and really think I may have a problem with my unit? Don't mean to be badmouthing anyone's baby.

cnh

renowilliams

Thanks for the input guys. I'm getting the Rotel for now...later I may get another but for now I'll give this one a try.

inspiredsports

cnh wrote: »

It might just be my NAD. I know some of their amps have reliability problems? So I'm not really disagreeing with you. I've used a Harman Kardon HD990 with the NAD--a decent upsampling CDP--with LSI-7s and they were too 'bright' for my ears on many Redbook CDs. Just telling it as I hear it...no foul meant.

As for 13Khz, you know I can barely hear that high....they call it 'age'? So maybe it's not the tubes but my aging eardrums? If I can hear to 14K it's a GOOD day! You know...it's how most people over 40 can't hear the high end anymore (much over 14 or 15K) and less than that if they've attended too many Rock Concerts in their youth.

I should add that my ears, as declining as they are, detect any harshness in 'digital' sound and are disturbed by it. When I say 'warm' I mean REALLY warm not just a hint of it. Which is one reason I am seriously considering a tube stage CDP.

I'm open to the NAD sound and really think I may have a problem with my unit? Don't mean to be badmouthing anyone's baby.

cnh

No I didn't take it that way. Just curious which comes first, the chicken or the egg, in your chain of components :biggrin:

Vintage NAD's did suffer power relay problems after 15-20 years as they use physical contact points that burn/oxidize after years of use. They are also notorious for a cold solder joint or two in maybe 1 out of 30 units after a decade or more. The nice part is it's absolutely worth having them recapped and rebuilt as they then sound even better than when brand new and are ready to go for a few more decades.