What amplifier/amplification power (watts per channel) do I need for my SDAs?

cdistler

I've been looking for this info for a while and people have said it's all over but I haven't been able to find it so I'd like to request general responses for others who need this info. I've found plenty of posts about power recommendation for the SRS's but not the lower end SDA.

I now have the SDA2's or 2b's (they just say SDA2 on the back but only have 2 mids and on tweeter). But am planning on switching to the SDA CRS because they're smaller and lighter and I move around often.

[TANGENT: This brings up another question: CRS vs. SDA2 or SDA 2b. Are the CRS almost as good? What differences can I expect?]

My particular setup and needs: I now have an Onkyo TX-8522. The audiophile geeks (compliment not disrespect) around here seem to talk down on such common brands or models as this amp but my needs (for the moment at least) are somewhat modest. I live in NYC (Brooklyn) and thus usually find myself in a small spaces. Even when I can crank it up when you're in a 10x10 room or smaller (or even a 12x12 room) you only need so much sound, irregardless of high ceilings. Still, I'd like the power/quality to fill a normal sized living room.

So I'd like to know both what are the power requirements to look for (and anything else I might not be aware to ask about), and if ya'll have any suggestions for brands and models. But I suppose the first question should really be: Is what I already have (the onkyo) good enough? what am i missing out on if anything? And I'm not looking to spend several hundreds of dollars on a new amp any time soon, maybe $300 max, used obviously is ok/good. And I get the feeling you guys will tell me I need to wait til I have more cash to get something on the level of my SDAs...

FYI: I listen to all types of music form folk to country, hip-hop, rock, classical, world, electronic, and plenty of blues. For what it's worth I have CD player, vinyl (preferred but limited selection) and increasingly listen to mp3s (irresistable temptation; 256-320 bitrate), so I'm not an extreme audiophile, I just don't want to run a porsha on a pinto engine.

Thanks much for your help!!!

Face

Quality is more important than quantity. The last few amps I've used with SDA's were 20-60 watts per channel.

I can't make a recommendation in that budget, but will recommend you lose the MP3's and rip everything in lossless.

ND13

I've had 2As and SRS 2s in a 455 Sq. ft. room. I ran the 2As off a HK 3380 stereo receiver at first and they sounded great. Then I used the pre-outs and used an AMC 2100 and they sounded better. Never ran them with tubes, other than the pre-amp(Dodd ELP).

I used at least a half dozen different amps with the SRS 2s rated any where from 305 wpc (solid state) to as little as 20 wpc(tubed). I've used tube amps with 75 wpc, 60 wpc, 50 wpc, 40 wpc and the ^^^^ mentioned. My favorite was, by far, the 40 wpc Anthem that George Daniels is about to use with his new SDA 1Cs.

If you're going to use SS, then I'd suggest something with gobs of current and headroom and rated somwhere between 100-200 wpc minimum. Unless it's a Class A amp, then you can go with less of a rating. SDAs are actually pretty efficient, but still can soak up a lot of power.

Good luck.

Conradicles

Look for an amp/receiver that has "high current" and is "4 ohm stable".

SDA-2B's are great, and I have 2 sets of them. By no means am I as experienced or as knowledgeable as most @ Club Polk, but I hear that Carver Amps are a very good mate with Polk.:cool:

For now, I have a harman/kardon and a Pioneer both rated @ 120 watts per channel, and I think the harman/kardon makes them sound a little better IMHO.

Hopefully I will get the chance to upgrade to a bigger amp for my 2 sets in the future, so I would like to hear what others here have to say as well.

bluecomet

I have all of the speakers you are interested in. The SDA 2B's are very good speakers but are somewhat heavy and can be a pain to move around. It is best to use a handtruck for them if moving. The CRS+ speakers are excellent and can easily be moved and would sound excellent in a small room, more than enough power for any music. If it is a physical hassle to move the SDA 2B's around I would look for the CRS+ speakers. They would be a better match for someone in a small room . You may losea little base but in a small room I doubt if you will notice it much. Both are great speakers. Can't go wrong with either.

cdistler

Thanks, but break it down a little more for me if you can guys. I'm still just learning about the electronic specifications. tubed/tubes, as compared with what?, solid state?, class A? i know it's probably the prereq for 101 but at the very least let me know which i have? sounds like i don't have class A. is the onkyo class B? and solid state not tubed?

in general i prefer warmer sounds (vinyl) and like old-school gear as probably many do here i imagine. so i imagine i might prefer tunes??

as for lossless i was afraid someone would say that. it'll be hard to go back and get those albums in better quality but if you think it makes a huge diff. I may do it from here on out and see if i get get my favorites in better quality. I had decided on 256 after doing some tests myself ripping to different bitrates and the original wave format and couldn't notice a difference (but I think I was listening on headphones, but good headphones.)

Just to be clear: I think I'm getting the message that even in a small space my onkyo is significantly less than ideal?

[and fwiw: the onkyo does have "full bandwidth" or RMS power (again 100wpc) and um, a variable ohm rating that can go down to 6ohms for the SDA 2, but I have a feeling I just made myself look more ignorant than I already did]:D

cdistler

Thanks bluecomet. i was looking at a pair of the crs+ for $250, real wood and apparently very good or excellent condition...what do you think?

Conradicles

harman/kardon has the "warm sound" and is very capable of driving Polk speakers. I got mine for ~$125 used and love it.

ND13

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1236792795&/Onix-A2150---P-3000

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1236813775&/Rotel-RB-971

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1236790532&/B-K-ST-202-plus

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1236555334&/NAD-C272

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1236444204&/Classe-Balanced-70-amp-$450-or

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1236441287&/Rotel-RB-980-BX

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1236292260&/Parasound-HCA-1500A

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1236122872&/Odyssey-HT-2-ODL

Here's a few used amps that will fill your needs if you have a preamp or pre-outs on the back of your Onkyo. There are many more and you can look into the integrated amps, too.

bluecomet

250.00 dollars for a pair of CRS+ speakers plus interconnect cable would be a good deal if they do not need new tweeters or have any issues. They are an excellent speaker for someone with a small apartment and they rock. I would go for it.

dbnh

Conradicles wrote: »

Look for an amp/receiver that has "high current" and is "4 ohm stable".

+1 re: "high current" amp (or mono amps, as is my case. Caveat - some SDAs may have an issue with mono amps, the search fx is your friend here.)

0 / -1 re: receiver. Not sure that a combo (amp + preamp + tuner = receiver) unit will give you what the SDAs need re: high current and low ohm stability.

I know from my gear that the SDA 1Cs thrive on high current, low ohm stability mentioned by Conradicles. For me, cleaner and higher current powered high quality amps make these speakers sing. Of course, replacing tweeters, and having ben62670 attend to the speakers' crossover upgrades (Ben, you rock!) were of significant help. Then there's the Mortite tweek! Plus quality components upstream. And Walker SST! And aftermarket powercords and ICs! etc, etc, etc!

Happy listening, and best of luck with your decision making. Enjoy the journey.

george daniel

I'll second what Noel said,, I think that a 40-50 watt tube stereo amp would be a nice match with the 2's. The little 40 watt Anthem that I got from him will turn some heads. Good luck with whatever you decide on. Like others have said,, it not necessarily the wattage, but the current,, and source.

Conradicles

His max is $300.
Can a good tube amp be got for that price?

I have yet to hear a tube amp, but sounds very interesting. How much did the Anthem 40 watt tube amp cost GD if it is O.K. to ask?

cdistler

hmmm, looks like my onkyo 8522 doesn't have preouts. that's too bad. i just found a Rotel Amp RB-970BX for $50. maybe i'll try to find an old integrated tube amp. and just ditch the onkyo.

to be sure, there's no way to use my current amp/receiver with something like that rotel right? or if it could work it wouldn't make sense b/c i'd only get power from the rotel??

Thanks for everyone's help!

PS- any opinions on this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=370141863537

inspiredsports

Welcome to Club Polk. I've been driving SDA-2B's with an NAD 7600 Receiver. I purchase both new in 1987. I just bought a set of SDA SRS 2's and and NAD 1700 preamp/tuner and 2600A Amp in November. The 7100+2600A separates are the identical components within the 7600. A 1600 preamp/tuner could be substituted..

I have been watching these components on eBay and they can consistently be had for between $250 and $300 delivered to your doorstep.

These NAD products are high current and deliver 150 watts per channel into ohms and over 200 wpc into 4 ohms all day long.

cdistler

ok, so i would need both the pre-amp and the amp? i have to say i'm a little shocked, i mean i knew i had badass speakers but i didn't realize that i had to have such crazy high-end equipment to power them, especially since they're the "lower end" of the sdas and need less power than the srs, etc. don't my (prospective) crs+ need a lot less power than your srs 2's?

if i go that route, are they 250-300 together?
i see a 1700 (no remote) for about $100. or the 1600 for btwn $150-200 w/ remote)...

strider

You don't need to have high end anything to make the speakers work.

The equipment you'd need to start hearing what the speakers are really capable of, however, some may consider high end.

Your receiver will power them, and they'll probably sound pretty good. If you get the chance to hear what they sound like with seperate components (a preamplifier and an amplifier), you won't be happy listening to the receiver again.

Both the 2Bs and the CRS+ are great speakers even if they're at the low end of the SDA hierarchy. If the CRS+ fit your lifestyle better, get 'em, sell the 2Bs, and rock on. Hell, use the Onk for a while and use the time to do some research, save some coin, and get some seperates.

FWIW, I really started getting serious with this stuff two and a half years ago when I got my 2Bs. With them, I started with a Carver pre amp and amp rated at 250 watts per channel. Last year I got a Rotel pre and amp that puts out 120 wpc. I enjoy the lower power Rotel much more.

Whatever path you decide on, remember to have fun and listen to music. We're here if you have questions, or are having a problem spending your money.

Ben

cdistler

Thanks Ben!
that helped.

Bigerik

My 1B's have been very happy with my two Carver amps: m1.0t and a tfm-45.

Schurkey

NOTE: This started out as a simple reply; and the more I type the more I think of that needs to be said. "Audio" encompasses design, manufacturing, philosophy, economy, perceptions, and emotions even before you turn the thing on and play the music. And I have other chores to do; so I'm calling it quits here. But I'm surely not "done"--just as done as it's gonna be, at least for now.

cdistler wrote: »

I live in NYC (Brooklyn) and thus usually find myself in a small spaces. Even when I can crank it up when you're in a 10x10 room or smaller (or even a 12x12 room) you only need so much sound, irregardless of high ceilings. Still, I'd like the power/quality to fill a normal sized living room.

So I'd like to know both what are the power requirements to look for (and anything else I might not be aware to ask about) and if ya'll have any suggestions for brands and models. But I suppose the first question should really be: Is what I already have (the onkyo) good enough? what am i missing out on if anything? And I'm not looking to spend several hundreds of dollars on a new amp any time soon, maybe $300 max, used obviously is ok/good. And I get the feeling you guys will tell me I need to wait til I have more cash to get something on the level of my SDAs...

Thanks much for your help!!!

First Guess: The Onkyo is as good as anything for your needs right now considering you've limited other choices to a fairly low price point.

This is not to say that the Onkyo is the best amp for your purposes; or that you couldn't find a better one for $300. I'm just saying--you're better off to use what you have FOR NOW and wait to upgrade the amp until 1) you actually need more volume than you can comfortably get now; and 2) your budget can stretch a few hundred dollars (or more) higher so that you can get an amp that is "more" better (rather than "marginally" better) than the one you have.

Face wrote: »

Quality is more important than quantity. The last few amps I've used with SDA's were 20-60 watts per channel.

So true. But how do you define "Quality"??? Especially to someone who doesn't have a background of experience in amplifier power/distortion/circuitry design? The "perfect" but low-power amp will sound terrible if you overdrive it. High-power amps (COMPETENTLY but not "perfectly" DESIGNED AND BUILT) still tend to sound quite good at lower volume levels.

Quantity is much easier: HOW MUCH POWER you need is DIRECTLY related to HOW LOUD you want the sound to be. And it's a logarithmic scale; double the volume and you need ten times the power--little volume changes make a big difference in watts required.

Conradicles wrote: »

Look for an amp/receiver that has "high current" and is "4 ohm stable".

I don't know what the SDA 2 series is "rated" for impedance; my SDA 1Bs are nominally 4-ohm. The speaker rating is somewhat deceptive; impedance varies with frequency--and so a speaker may have a part of the frequency spectrum where it measures 2-ohms; and another part of the spectrum it might measure 16 ohms. But "overall" it's considered to be a "4-ohm" or "6-ohm" or "8-ohm" speaker.

Short story: "Better" amps will tend to be stable into lower-impedance loads. The "best" amps will be stable into a 1-ohm or lower load. Don't expect that kind of current delivery to come cheap. And--for the purposes of Polk speakers in general--1-ohm stability almost certainly isn't needed. 4-ohm stability is VERY desireable. 2- or 3-ohm stability is probably desirable. Good luck.

• VOLTAGE is CHEAP. AMPERAGE (current) is EXPENSIVE. "Watts" = Volts X Amps; which is why modern, consumer-grade Communist CRAP amps may deliver a "rated 200 watts", but completely **** the bed when connected to a 6-ohm speaker. Reduced impedance requires more current--and they can only provide minimal current, but all the voltage in the world.

There is no "legal" standard; and no single "Industry Standard" for measuring current delivery of an audio amp for short durations or "impulse" testing. One "Famous Name" amplifier company, when asked about the "current delivery" of their "high current" amps, liked to claim "Whatever you want it to be". In other words, if you wanted "80 amps" of current, they could find an impulse short enough so that their amp could deliver that much current. If you wanted more, they could shorten the impulse to suit. Is this musically important? No, not really. Don't be taken in by crazy amperage specs--40, 60, 80 amps is NOT POSSIBLE for any reasonable length of time; and it doesn't matter anyway if the impulse isn't in the frequency range where your speakers are at the lowest impedance.

cdistler wrote: »

break it down a little more for me if you can guys. I'm still just learning about the electronic specifications. tubed/tubes, as compared with what?, solid state?, class A? i know it's probably the prereq for 101 but at the very least let me know which i have? sounds like i don't have class A. is the onkyo class B? and solid state not tubed?

"Class A" and "Class B" mean different things to different people. Specifically, there are Industry Standards for how output devices are integrated into a circuit. And there are MARKETING TRADEMARKS which carry NO industry standard; but are designed to fool people into thinking they're industry standards. So an output tube--or transistor-- may be operated in Class A; Class B, Class C or Class D. Those are industry standards. Class C is not suitable for audio uses. Class D was historically used for subwoofer amps; only recently has "modified" Class D become suitable for full-range audio.

That pretty much leaves Class A and B. Class A is very inefficient, heavy, and high-temperature. Therefore, Class A is EXPENSIVE. Your Onkyo does not use "Class A" output circuitry. On the other hand, Class A can be very "pristine" sounding. Class B is WAY more efficient; less heavy, less hot, less expensive. Also less pristine. And so there's a variation--Class AB. Your Onkyo--like most everything else--is almost certainly Class AB. Some of the efficiency of Class B, some of the sound quality of Class A--how much of either depends on where in the sliding scale of Class AB your amp is: Your Onkyo is probably much closer to B than A, you'll have more of the advantages of B.

The other "Class" system is provided by reviewers: principally Stereophile magazine. "Class A" power amps are simply the "best sounding", B is not as good-sounding as A; C is not as good sounding as B--you get the idea. Has nothing at all to do with the design concepts. It would have been less confusing if they'd have used "5 star--4 star--3-star" or whatever as a rating scale.

"Tubes" versus "Solid State" is like arguing which keeps food longer--glass jars or steel cans. Both have problems. Both have advantages. Both are hampered by the quality of the actual parts used in the circuit, AND the design and layout of that circuit. "Good" tubes are more expensive than "ordinary" tubes; "Good" transistors are more expensive than ordinary transistors. Tubes in general are more expensive than transistors, which means that IN GENERAL tube amps are less powerful than transistor amps.

cdistler wrote: »

and fwiw: the onkyo does have "full bandwidth" or RMS power (again 100wpc) and um, a variable ohm rating that can go down to 6ohms for the SDA 2, but I have a feeling I just made myself look more ignorant than I already did]:D

6-ohm stable is "probably" enough for your SDA 2s, especially if the volume isn't up too high--which seems to be the case. Your Onkyo is somewhat current-limited; but if you keep the volume (voltage) low enough, the current will be sufficient. YES, you can do better. Someday you'll want to upgrade. It doesn't have to be TODAY.

strider wrote: »

You don't need to have high end anything to make the speakers work.

The equipment you'd need to start hearing what the speakers are really capable of, however, some may consider high end.

Your receiver will power them, and they'll probably sound pretty good. If you get the chance to hear what they sound like with seperate components (a preamplifier and an amplifier), you won't be happy listening to the receiver again.

True; but also somewhat volume-dependent. And I don't rule out a "good" receiver sounding better than Communist-Consumer-Grade Junk separates. The Onkyo is probably fine for his present usage; but he'll maybe get into trouble if he increases the volume level enough to outpace the current-delivery capacity. Again, I'm not saying that he couldn't get better sound out of the speakers, but of all the things he's said, he has NOT said that he dislikes any aspect of the sound he is getting.

There's a whole 'nother debate on DISTORTION; what distortions are most important; which are less important; how much distortion is audible. Some say that any distortion that is commonly known about has already been minimized by design into insignificance. What can I say? Any distortion is bad. ALL amplifiers have several kinds of distortion. At a price point of "Under $1K" you look for small numbers on the published distortions, and you don't think too hard about how many dB of feedback the thing has; or if there are new and exotic forms of distortion that haven't been discussed.

dudeinaroom

I'm sooo sorry to do this but...... we do have a search function on this web site that works pretty well. I don't even know who many times I have seen this same question asked recently. No problems asking questions, but a little searching can go along way. I know some of the senior members will see the post and say not another. The search will give you the good feeling of knowing you found what you were looking for, make you more educated, and give you some respect. If you don't find exactly what you are looking for, then by all means ask away. Just take a little initiative first, and if you have I'm sorry for this post. Just a lot of noobs lately asking the same questions that have been answered umpteen times.

Now back to your previous scheduled thread.

Later,
dude