Amplifier/power recommendation for vintage SDAs

Joshwest90

I have a pair of the following: SDA-1A, SDA-2A and a pair of SDA-84CRS. I have the 1A as front channel approx 6” from the wall, 12 foot apart, the 2A as rear channel 6” from the rear wall 12’ apart, and the 84CRS as sound surround.

I currently have them being ran from a Denon AVR3803. It puts out an advertised 125WPC @ 8ohm. I’ve not checked this to see if it is accurate.

My question is about these Polks. What is their efficiency? What is their specs, What power handling makes these really shine without straining them? Any recommendations for power amplifiers? Any recommendation on placement? I use this system as a HT as well as listening to music. I came to this page from advice from other polk fans. Let me know guys/gals!

pitdogg2

Carver / Sunfire
Parasound
B&K
Some Adcoms, not all Adcom gear is common ground keep in mind.
Rotel
Etc. Etc. Etc.

Use the search function we have laid this out millions of times here.

F1nut

What the heck is a 84CRS?

Joshwest90

The year the CRS was made. That way people knew what model i was referring to. Missed the (‘)

F1nut

Ah, more commonly referred to around here as the blade/blade version.

You need a 5 channel power amp.

ThomasD

Interesting, I've got 2 out of 3 of your speakers myself. Hadn't really thought about using them for an all SDA HT. Seems like it would be a fairly tight 'sweet spot' to really enjoy the maximum SDA efficiency of each pair. Mine really start to sing (in 2 channel) when pushed with my SS Carvers (I know, not to everyone's liking). But as @F1nut noted, AVR's have their inherent sonic limitations due to their multi-tasking responsibilities. Believe the 2a's were rated @88db's, the 1a's @90db's & the CRS's @90db's also.
@Joshwest90 By the way, Welcome. Lot's of folks here with an acute knowledge of Polks & all things audio. Enjoy

sevendogsbsd

I am running my SDA2-A's with a Carver M1.0 and they sound great. I actually have 2 of these amps and would love a set up where I can run them as dual mono, but alas this will involve replacing the Polks. For a 31 year old system (bought the Carver M1.0, C-2 and Polks all at the same time in 1988), it still sounds great. I have not clipped the amp or engaged the polyswitch on the SDAs to date, and they get plenty loud. I do wish they had more bass impact but I have a relatively large listening room.

ThomasD

My Carver1.0t is what I've been driving my 2a's with also. Have not felt that the bass was lacking on my un-restored 2a's with the Carver power. The 2'a x/o's are currently with @westmassguy for a complete TL update and I have a recently refurbished 4.0t w/200 watts per channel that will be delegated to the 2a's. The 1.0t will then be used for the CRS's. Just been real satisfied with using Carver power for all SDA's.

Joshwest90

I’m looking at getting (2) Carver M-400 cubes they are 200 Wpc to drive the 1A and 2A. Anyone have experience with these? @ThomasD thank you! There is so much info here! I’ve prob frustrated the originals with asking a question that’s been answered numerous times. Just hard to really understand and get the info locked down.

Joshwest90

Just followed an old thread and it looks as if the M-400 cannot be used with the SDAs due to common ground issues. Slightly frustrating. I really don’t want to have to modify the SDAs to accommodate an amp.

FestYboy

You don't mod the speakers, you mod the IC, but only if it's pin/blade.

What is your center channel?

ThomasD

The 1a’s & 2a’s do need a common ground amp. Not aware of any mods on a blade/blade SDA that would alleviate that requirement. I’m not familiar with the Carver cubes but I do believe your right that they are not common ground.

Joshwest90

@FestYboy my center channel I’m currently using is the definitive technology Pro center.

@ThomasD I found an old posting where Bob carver sent a user a letter regarding these amps and SDAs you can only use the left channel from each amplifier. Subsequently you’ll get 3-350 watts to the one channel, but essentially two amps for 2 speakers instead of 1 amp to 2 speakers

pitdogg2

There are other carver amps the same way as they invert one channel. You cannot modify any of your speakers to use mono or non common ground amps.

F1nut

Joshwest90 wrote: »

I’m looking at getting (2) Carver M-400 cubes they are 200 Wpc to drive the 1A and 2A. Anyone have experience with these? @ThomasD thank you! There is so much info here! I’ve prob frustrated the originals with asking a question that’s been answered numerous times. Just hard to really understand and get the info locked down.

That is one piss poor sounding amplifier.

Joshwest90

F1nut wrote: »

Joshwest90 wrote: »

I’m looking at getting (2) Carver M-400 cubes they are 200 Wpc to drive the 1A and 2A. Anyone have experience with these? @ThomasD thank you! There is so much info here! I’ve prob frustrated the originals with asking a question that’s been answered numerous times. Just hard to really understand and get the info locked down.

That is one piss poor sounding amplifier.

Lol I love the blunt response 😂😂

I’ve been scouring the forums and I can’t seem the find the one page that describes the best sounding amplifier for the polks.

sevendogsbsd

I have also been told my M1.0 is a terrible sounding amp. Shame, I guess I have not really been enjoying that last 31 years of listening. And I thought I was happy.

F1nut

I thought what I had 31 years ago sounded good too. I was wrong.

Joshwest90

@F1nut recommendations?

F1nut

Budget and are you looking for a 2 channel or 5 channel amp?

dromunds

My college roommate bought those Carver M-400 cubes new. You can do a whole lot better, plus I thought I read one time that there was a problem with them starting on fire but that's something you can easily find with a good internet search. I was never impressed with them in any event.

Joshwest90

F1nut wrote: »

Budget and are you looking for a 2 channel or 5 channel amp?

I would like to buy a monolith or Emotiva 5 to 7 channel amp, but I figure if I just get 2-2 channel amps for the SDA 1 and SDA 2 it will get me to where I want to be. Right now I think the Denon 3803 is struggling with 3 pairs of polks on it and a set of definitive towers

The m400 the guy was wanting 120.00 a piece if I could find something solid for around that I would be interested, but I’m open to anything

Joshwest90

Would like atleast 200 WPC

ddog

A lot love for Parasound amplifiers here on.

F1nut

Joshwest90 wrote: »

F1nut wrote: »

Budget and are you looking for a 2 channel or 5 channel amp?

I would like to buy a monolith or Emotiva 5 to 7 channel amp, but I figure if I just get 2-2 channel amps for the SDA 1 and SDA 2 it will get me to where I want to be. Right now I think the Denon 3803 is struggling with 3 pairs of polks on it and a set of definitive towers

The m400 the guy was wanting 120.00 a piece if I could find something solid for around that I would be interested, but I’m open to anything

No doubt about it, the AVR is sruggling with those speakers.

I can't think of anything worth buying in the $120.00 price range and I'm no fan of emo gear. The Parasound suggestion is good, but will cost more money.

Joshwest90

F1nut wrote: »

Joshwest90 wrote: »

F1nut wrote: »

Budget and are you looking for a 2 channel or 5 channel amp?

I would like to buy a monolith or Emotiva 5 to 7 channel amp, but I figure if I just get 2-2 channel amps for the SDA 1 and SDA 2 it will get me to where I want to be. Right now I think the Denon 3803 is struggling with 3 pairs of polks on it and a set of definitive towers

The m400 the guy was wanting 120.00 a piece if I could find something solid for around that I would be interested, but I’m open to anything

No doubt about it, the AVR is sruggling with those speakers.

I can't think of anything worth buying in the $120.00 price range and I'm no fan of emo gear. The Parasound suggestion is good, but will cost more money.

What are your thoughts on crown 1500, carver m-1.0t, parasound a21,a23, monolith 7x, any other suggestions in open to i figure around 120.00 would be junk

Schurkey

Anything old will need to be serviced. The basic design may be fine--but it'll need new caps, maybe some matched transistor pairs, cleaning, adjusting...this will at least double the purchase price and almost certainly more than that.

The Monolith amp appears to be another custom-branded ATI unit, just like ATI makes custom-branded amps for Outlaw. ATI has a good reputation and a long history, but not all of that history is strictly-speaking part of ATI as a brand.

$120 is not just dreaming, it's a fully-spurting wet dream.

Joshwest90

@F1nut @Schurkey @ddog any thoughts on ADCOM GFA 535,545, 555
BEHRINGER EP1500
BEHRINGER EP4000
Crown CTS1200
Hafler xl280
B&K ST125.2

ddog

Joshwest90 wrote: »

@F1nut @Schurkey @ddog any thoughts on ADCOM GFA 535,545, 555
BEHRINGER EP1500
BEHRINGER EP4000
Crown CTS1200
Hafler xl280
B&K ST125.2

There's a lot of love for the Adcom 555 and B&K amplifiers paired with Polk speakers.
Personally I have never owned any of the amplifiers you have listed.

I do own 1st and second gen Emotiva amplifiers and really like them.
Gen 2 XPA-2 would be a great amp and it has really nice size capacitors in too.

I also own a great number of Caver amplifiers and really like them as well.

Schurkey

Joshwest90 wrote: »

@F1nut @Schurkey @ddog any thoughts on ADCOM GFA 535,545, 555

Well-regarded, will need servicing.

Joshwest90 wrote: »

BEHRINGER EP1500
BEHRINGER EP4000
Crown CTS1200

Absolutely no idea. Never heard any of them, never had interest in them. Typical "Pro" amps don't have a good reputation for sound quality, but you get a lot of watts in a small box at low price. The Crown Macro Reference got some ink in Stereophile ten or fifteen years ago...but I don't know how representitive it is of the brand.

Joshwest90 wrote: »

Hafler xl280

The only friend I have that's into audio has a bunch of DH500s, an XL280, some DH220s. He loves 'em. He's never cooked one, (He's popped an input circuit board or two) but he's bought some off of eBay that showed up with melted transistor leads (claimed as "shipping damage". He says that "FET" stands for "Flame Emitting Transistor".) The DH500/XL600, and the DH200/220/XL280 are well-regarded, proven, and have aftermarket support to make them even better.

Thousands and thousands of years ago, we were both early in our careers. I rented a room from him in his trailer. He'd built a DH500 from the kit, he had homebuilt speakers, and we'd turn the volume up until the tweeter-protection fuse started to glow. I think the "fuse" was actually a certain wattage automotive light-bulb. As it got hot, it'd glow, and of course the filament would gain resistance cutting power to the tweeter. Stevie Nicks and Dire Straits still get me going.

Joshwest90 wrote: »

B&K ST125.2

Again, B&K is well-regarded. Essentially out-of-business (part of the ATI amplifier empire, but I don't think they've had any B&K-branded product for a decade)

One brand you're missing is Acurus. A250, 200X3, A200X3, and the lesser-powered bretheren are well-regarded, reliable, powerful into low-impedance loads. I've not gotten my main amps set-up since moving; I'm using a 200X3 to drive my modified SDA 1Bs and a center channel. Works so well...that I've never bothered to set up the main amps. Just too lazy, I guess. That, and the fact that I'll have to rewire the house to supply enough power.

There's LOTS of suitable choices. What you buy will largely depend on what you can find locally; or how much risk you're willing to take on eBay, Craigslist, or the various used-gear marketplaces in forums like this one.

Joshwest90

@Schurkey awesome write up thank you! Regarding the adcom; Is there a write up that discusses what work is required?