amp for my SDA-1A's

g-man
g-man Posts: 46
edited January 2005 in Vintage Speakers
Hi,I know you'd read this F1nut,and I have a question.You said that I shouldn't use a non-common ground amp for my SDA-1A's,nor should I use mono blocks...why..? Is it because of the interconnect cabel between the speakers? I can't seem to find any other reason than that..

G-man
Stereo:
Speakers:Polk SDA-1A
cd/dvd:Marantz DV6200(HDCD)
Amp: DUAL Audiophile Concept. (1992)

ICE:
Alpine CDA9887R
Audison LRX 1.1K
Audison LRX 4.5
Amega Q-Comp50
Amega Q-Comp60
Sub: Focal Utopia WX21 BE
Sub:? maybe 3 MM840.
Stinger HPI signal,power,speaker cables
Post edited by g-man on
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Comments

  • Tour2ma
    Tour2ma Posts: 10,177
    edited January 2005
    Yup... the standard SDA interconnect establishes a circuit connecting the grounds of the left and right channels. To an amp (or amps) that cannot tolerate that, it's a short, and those are never good.

    Most 2-ch amps are common ground designs, but not all are.

    Some Mono-blocks can handle their negative (or ground) speaker terminals) being wired together, but not all can.

    What amp(s) do you have in mind?
    More later,
    Tour...
    Vox Copuli
    Better to remain silent and be thought a fool, than to open your mouth and remove all doubt. - Old English Proverb

    "Death doesn't come with a Uhaul." - Dennis Gardner
    "It's easy to get lost in price vs performance vs ego vs illusion." - doro
    "There is a certain entertainment value in ripping the occaisonal (sic) buttmunch..." - TroyD
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  • g-man
    g-man Posts: 46
    edited January 2005
    I've been looking at many different amps such as the Meridian 557,the Electrocompaniet AW120,Pas Lab,McIntosh, and a Carver amp..(F1nut recomended a carver,but I'm not sure where to get one here in Norway).But the one I'd like to have is the McIntosh or the Meridian.Theesa amps costs allot,so I'm looking for a used one..can't buy them from the US because of the voltage isn't the same..(240V here.)

    G-man
    Stereo:
    Speakers:Polk SDA-1A
    cd/dvd:Marantz DV6200(HDCD)
    Amp: DUAL Audiophile Concept. (1992)

    ICE:
    Alpine CDA9887R
    Audison LRX 1.1K
    Audison LRX 4.5
    Amega Q-Comp50
    Amega Q-Comp60
    Sub: Focal Utopia WX21 BE
    Sub:? maybe 3 MM840.
    Stinger HPI signal,power,speaker cables
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  • Tour2ma
    Tour2ma Posts: 10,177
    edited January 2005
    NAD should be avaialble to you. They're a good choice and an UK company.

    Fair amount of used 2-ch availability, at least over here...
    http://www.nadelectronics.com/index.htm
    More later,
    Tour...
    Vox Copuli
    Better to remain silent and be thought a fool, than to open your mouth and remove all doubt. - Old English Proverb

    "Death doesn't come with a Uhaul." - Dennis Gardner
    "It's easy to get lost in price vs performance vs ego vs illusion." - doro
    "There is a certain entertainment value in ripping the occaisonal (sic) buttmunch..." - TroyD
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  • g-man
    g-man Posts: 46
    edited January 2005
    There's allot of used NAD's here,but do you think they have what it takes to reproduse a natural sound..? I have owned several NAD's thru the years,but I think that the SDA's could use a better amp..The only amp from NAD could be the Silverline S300.It delivers 2x100W in 8 ohms.Do you think that's enough..?
    How about the Meridian 557..?
    Or the McIntosh MC275..?

    G-man
    Stereo:
    Speakers:Polk SDA-1A
    cd/dvd:Marantz DV6200(HDCD)
    Amp: DUAL Audiophile Concept. (1992)

    ICE:
    Alpine CDA9887R
    Audison LRX 1.1K
    Audison LRX 4.5
    Amega Q-Comp50
    Amega Q-Comp60
    Sub: Focal Utopia WX21 BE
    Sub:? maybe 3 MM840.
    Stinger HPI signal,power,speaker cables
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    Hey G-man, I recommended a Carver? I don't recall that....lol.

    I think either one of your other choices would work well, especially the tubed Mac.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • g-man
    g-man Posts: 46
    edited January 2005
    ooops..! sorry F1nut..my bad...Cary V12..missread.I'm Norwegian for crying out loud..!! :D but anyways..you think the Meridian is a good one..? I've listen to the Meridian on a pair of JMLab Electra and man did that sound great.! The Mac is just a wet dream actually...very hard to find a used one here and they cost alot,but I have the Meridian 557 power amp and the Meridian 501 (or the 861) pre-amp available at a store close by..going to visit the store monday morning when they open..with a fist full of cash..lol..

    again..thanks guys.

    G-man

    PS..

    what do you think of my home theatre system..had it for 3 years now..still going strong..:)
    Stereo:
    Speakers:Polk SDA-1A
    cd/dvd:Marantz DV6200(HDCD)
    Amp: DUAL Audiophile Concept. (1992)

    ICE:
    Alpine CDA9887R
    Audison LRX 1.1K
    Audison LRX 4.5
    Amega Q-Comp50
    Amega Q-Comp60
    Sub: Focal Utopia WX21 BE
    Sub:? maybe 3 MM840.
    Stinger HPI signal,power,speaker cables
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  • reeltrouble1
    reeltrouble1 Posts: 9,312
    edited January 2005
    Let me add to Tour2ma suggestion for the NAD, I have used the 2600A and 2700 with excellent results on my 1C's. You want something that will push something around 200 wpc at high current into the 1A which are nominal 4 ohm speakers.

    Many folks here use Carver and Parasound to drive their SDA and report excellent results.

    RT1
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    G-man,

    Meridian makes great gear, but I think you're going to have a problem with the 557 because it's dual mono and might not be a common ground amp. You can not use a non-common ground amp with those SDA speakers. You should check with your dealer and/or Meridian about that situation.

    Sorry, I should have mentioned this earlier.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • g-man
    g-man Posts: 46
    edited January 2005
    I'm glad that some know more about amps than me...:D I've never had to check how they are built before,but since I now have a pair of "rare" loudspeakers,I should check this out from now on..
    Got another amp suggestion: The Rotel RB990BX and the Rotel RA950RTC pre-amp..? The guy who's selling them wants $890 for them.Mint condition.

    G-man
    Stereo:
    Speakers:Polk SDA-1A
    cd/dvd:Marantz DV6200(HDCD)
    Amp: DUAL Audiophile Concept. (1992)

    ICE:
    Alpine CDA9887R
    Audison LRX 1.1K
    Audison LRX 4.5
    Amega Q-Comp50
    Amega Q-Comp60
    Sub: Focal Utopia WX21 BE
    Sub:? maybe 3 MM840.
    Stinger HPI signal,power,speaker cables
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  • Tour2ma
    Tour2ma Posts: 10,177
    edited January 2005
    Rotel amps have a good following around here. Nice, high current designs... At 200 wpc the 990 should be more than enough for the 1A's.

    I have no knowledge, 2nd hand or otherwise, of the pre....

    Stateside, looks like $875 would be on the high side for that combo. Mint, the amp looks to go in the $400 to $450 range, and the pre in the mid-200's.
    More later,
    Tour...
    Vox Copuli
    Better to remain silent and be thought a fool, than to open your mouth and remove all doubt. - Old English Proverb

    "Death doesn't come with a Uhaul." - Dennis Gardner
    "It's easy to get lost in price vs performance vs ego vs illusion." - doro
    "There is a certain entertainment value in ripping the occaisonal (sic) buttmunch..." - TroyD
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  • patwhite
    patwhite Posts: 9
    edited January 2005
    I am the owner of an nad 2200pe...plenty of power, but it can only be used with speakers that are non common ground since this amp can be bridged to become a mono amo....at one time, polk would swap out the connecting cable with one that could be used for non common ground amps.
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    Hold on Pat, your NAD is a common ground amp and only becomes a non-common ground amp if it's bridged. The cable you're speaking of is called the AI-1, but it can't be used with G-man's speakers.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • patwhite
    patwhite Posts: 9
    edited January 2005
    my owners manual clearly says don't use the 2200 nad amp with speakers that share a common ground....case in point, a friend of mine years ago with the same amp bought a pair of sda 2b's hooked them up to the nad using the provided interconnect and promptly blew the tweeters...we went back to the store and the salesman who just happened to have sold NAD in the past had the lightbulb go off and said..wrong interconnect..got the right one, hooked em up...no problems...
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  • hoosier21
    hoosier21 Posts: 4,411
    edited January 2005
    Originally posted by patwhite
    my owners manual clearly says don't use the 2200 nad amp with speakers that share a common ground....

    That is very interesting, I have had Polk SDA's and about every NAD amp including the 2200, never had a problem, not 100% sure I used the 2200 with SDA's, but I can't imagine I didn't.

    The later models, of NAD 2700, 2600, 2400, 2100 have all been used with SDA's with no problem.

    Like I said interesting stuff on the 2200.
    Dodd - Battery Preamp
    Monarchy Audio SE100 Delux - mono power amps
    Sony DVP-NS999ES - SACD player
    ADS 1230 - Polk SDA 2B
    DIY Stereo Subwoofer towers w/(4) 12 drivers each
    Crown K1 - Subwoofer amp
    Outlaw ICBM - crossover
    Beringher BFD - sub eq

    Where is the remote? Where is the $%#$% remote!

    "I've always been mad, I know I've been mad, like the most of us have...very hard to explain why you're mad, even if you're not mad..."
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    Ok, a quick search around the net didn't give me much, so from what you're saying this NAD is a dual mono amp and that it can be bridged?
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • hoosier21
    hoosier21 Posts: 4,411
    edited January 2005
    Inverted channels for powerful bass
    The greatest power demands commonly occur at low frequencies. Bass signals are in phase (and virtually
    monophonic) in most recordings; thus when the bass waveform is strongly positive in the left channel, it
    usually is strongly positive in the right channel at the same time. As a result both channels draw current
    simultaneously from the positive half of the power supply, while the negative half sits idle. During the
    negative half of the waveform, both channels draw from the negative supply while the positive supply
    sits idle. In the NAD 2200 the right channel is internally inverted in polarity. When a bass waveform
    causes the left channel to draw current from the positive supply, the right channel draws its bass power
    from the negative supply, and vice-versa. This efficient usage halves the instantaneous drain on either
    supply, allowing much stronger bass to be reproduced without draining the supply.

    Maybe this is the problem?????
    Dodd - Battery Preamp
    Monarchy Audio SE100 Delux - mono power amps
    Sony DVP-NS999ES - SACD player
    ADS 1230 - Polk SDA 2B
    DIY Stereo Subwoofer towers w/(4) 12 drivers each
    Crown K1 - Subwoofer amp
    Outlaw ICBM - crossover
    Beringher BFD - sub eq

    Where is the remote? Where is the $%#$% remote!

    "I've always been mad, I know I've been mad, like the most of us have...very hard to explain why you're mad, even if you're not mad..."
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  • patwhite
    patwhite Posts: 9
    edited January 2005
    the 2200 has only one big power supply and the inverted bass feature...but I do believe it's the bridging issue that requires non common grounding. I also have a Proton d1200d which is dual mono but is not bridgeable...no common ground issues in the manual. however, on my smaller protons like the d940 and the d540, both bridgeable, it says not to use with common grounds.
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    Hoosier has hit the nail on the head!

    Just because you can bridge a amp shouldn't cause any problems unless you actually bridge it and it becomes a mono block. A dual mono amp is just like using two bridged amps, in a sense it would be two mono blocks in one chassis. You can not use a dual mono amp with the SDA's unless you use the AI-1 interconnect, the same goes for mono blocks or any non-common ground amp. So, in this case it's the inverted bass feature that's the issue, not that you can bridge it to a mono block.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • patwhite
    patwhite Posts: 9
    edited January 2005
    there you have it...use the right connector and you are good to go with that 2200. (I wonder if the inverted bass issue follows thru with my proton stuff as well? Both Nad and Proton used similar technology, though when comparing the nad 2200 with the proton d1200...both very powerful, the proton is more musical and detailed..in my humble opinion.
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    From my knowledge of the two companies, I would say yes, same issue. They are basically the same with Proton being slightly better than NAD.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • patwhite
    patwhite Posts: 9
    edited January 2005
    slightly better and "prettier". I used the 2200 years ago to power a set of '86 monitor 10b's. now those 10b's are in my basement audio room being powered by a proton d540 integrated. Still have the 2200 and need to sell it I suppose. the d1200 is in the family room hooked to an nad preamp with b and w speakers. Just ther other day, a fella from my area had an ad in the paper to sell a pair of sda/srs for 35 hundred. thought that was way too high! would be nice to have!
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    $3500.00......he's dreaming!
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • german
    german Posts: 22
    edited January 2005
    It seems,that the SDS 2-B eats a lot of power.So I'm too looking for some better solution,than my old Technics 7700k.In spite of its relativ high powerconsumption of 560 Watts,it seems that it works too hard for feeding the SDA.
    So I´m thinking about buying an Accuphase,or a Luxman,or,what would be cheaper, a Yamaha.What do you think?What sounds best?
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    You have a pair of SDA 2B's also?
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • german
    german Posts: 22
    edited January 2005
    @F1NUt
    only SDA 2-B---not also (Polk Auidios)
    German not G-man

    Perhaps my posting in this thread confused .But I read these other postings,and searching for an Amp fitting to the SDA ,is just my momentary doing.
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    Oops, my fault.

    Ok, are you looking for a amp or a receiver?
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • german
    german Posts: 22
    edited January 2005
    searching an amp,but I don´t know the maximum allowed input of the sda2-B
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    Max. rated at 350 wpc, but you could feed them more. Out of the 3 you listed I'd look into the Accuphase. What other choices do you have in Germany and what's your price range? The recommended minimum to drive the SDA's properly is about 200 wpc, but more important is a high current rating.

    BTW, 560 watts maximum of power consumption is not very much really. A amp rated at 300 to 350 wpc draws about 1800 watts maximum.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • g-man
    g-man Posts: 46
    edited January 2005
    Ok..so the real issue here is that I need to get that interconnect cable...the AI-1 and my amp problem should in theory be solved..?..So.wher can I get that cable.? does Polk have that one for sale..?

    and I got the Meridian 557 power amp and theMeridian 501 pre-amp for $2700. only demo used.A bit more that I imagined I'd use on a amp rack,but heck..it's high-end amps..!..:)

    PS.

    The prices you opperate with in the States.can't be compared with
    the Norwegian price range..so to clearify a few things,a Big Mac large menu costs $14 here..
    Imagine the costs for greate sound..:rolleyes:

    G-man
    Stereo:
    Speakers:Polk SDA-1A
    cd/dvd:Marantz DV6200(HDCD)
    Amp: DUAL Audiophile Concept. (1992)

    ICE:
    Alpine CDA9887R
    Audison LRX 1.1K
    Audison LRX 4.5
    Amega Q-Comp50
    Amega Q-Comp60
    Sub: Focal Utopia WX21 BE
    Sub:? maybe 3 MM840.
    Stinger HPI signal,power,speaker cables
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  • F1nut
    F1nut Posts: 50,592
    edited January 2005
    G-man,

    I mentioned this before, but I quess you didn't understand. You can not use a dual mono amp with your speakers, nor can you use the AI-1 either. The AI-1 only works with SDA models that have the pin/blade type interconnect cable, yours has the blade/blade.

    You'll either have to return the amp and get something different or find some SDA's with the pin/blade type cable.

    BTW, that MickyD food will kill you.....YUCK!
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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