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    SP14 or a second ST120

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    Digdug

    Posts : 18
    Join date : 2012-10-05

    SP14 or a second ST120

    Post by Digdug on Thu Feb 20, 2014 3:19 pm

    Hello Everyone,

    My current system: MC Cart - E.E. Minimax Phono - SP12 - ST120 - a pair of Paradigm Studio 100 v. 5 & subwoofer

    I've thought about purchasing a second ST120 and bi-amping the Paradigms, but I've also thought about spending that money on an SP14 instead. Any thoughts on which would be the better purchase?

    Thanks,
    Doug

    corndog71

    Posts : 444
    Join date : 2013-03-19
    Location : It can get windy here

    Re: SP14 or a second ST120

    Post by corndog71 on Thu Feb 20, 2014 3:48 pm

    I would recommend upgrading the crossovers of your speakers.  For a couple hundred bucks you can substantially improve the sound of your speakers by simply replacing the caps, resistors and possibly inductors with better parts.  Just about every factory made speaker compromises their crossovers with cheap parts. It would be a much bigger improvement than biamping.

    sKiZo

    Posts : 1285
    Join date : 2013-04-01
    Location : Michigan USA

    Re: SP14 or a second ST120

    Post by sKiZo on Thu Feb 20, 2014 5:16 pm

    One of each!  geek 

    Corndog mentioned crossovers, but I assUme your speakers aren't all that old to have component breakdowns that could affect sound, and seems to me Paradigm has some pretty decent parts to begin with. They're also BUILT to be bi-amped, which is a definite plus.

    HOWEVER

    I'd think you'd get more bang for the buck upgrading your pre to improve the signal itself before putting a lot of bucks into a bi-amp setup. Garbage in, garbage out, as they say.

    THEN AGAIN

    The SP12 isn't exactly garbage, ok.

    BUT

    Seems to me you wouldn't need the power of an ST120 to drive the top end on a bi-amp setup. Maybe an ST70 instead? And put the money you save towards an SP14 fund?

    daveshel

    Posts : 148
    Join date : 2011-11-06
    Location : Tucson AZ USA

    Re: SP14 or a second ST120

    Post by daveshel on Thu Feb 20, 2014 8:30 pm

    You could bi-amp and use your ST120 for the highs and get a less expensive solid state amp for the lows - concentrate the tubes where they matter.

    I wouldn't expect to hear a night and day difference between the SP12 and the SP14 (but then again I've never heard either one).

    Digdug

    Posts : 18
    Join date : 2012-10-05

    Re: SP14 or a second ST120

    Post by Digdug on Thu Feb 20, 2014 10:21 pm

    Oh my! I never thought of bi-amping with a solid state or going the route of the ST70.

    Thanks for all of the advice! You've all given me much to think about.

    sKiZo

    Posts : 1285
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    Location : Michigan USA

    Re: SP14 or a second ST120

    Post by sKiZo on Thu Feb 20, 2014 11:01 pm

    Just remember, it's not all about da boom ... You'd still want to go quality with the bottom end amp - I get a LOT more definition down there using tube power than I ever did with a solid state amp ...

    Digdug

    Posts : 18
    Join date : 2012-10-05

    Re: SP14 or a second ST120

    Post by Digdug on Thu Feb 20, 2014 11:22 pm

    I have a Marantz A/V receiver I'm not using. It's about three years old. I may just plug it in and see how it sounds in conjunction with the ST120, but my hunch is I'll be disappointed. Still, never know until I try! I put telefunken 12ax7's in my phono stage and they sound amazing except they're a bit bloomy and boomy in the bass department, so I don't want to do anything that takes away from the bass definition that's there. Still, if I don't like what I hear, I'll go put the Marantz back in the closet. No harm done.

    So, it's okay to bi-amp with completely different amps? I mean, it won't hurt my speakers to do so?

    corndog71

    Posts : 444
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    Re: SP14 or a second ST120

    Post by corndog71 on Fri Feb 21, 2014 11:26 am

    sKiZo wrote:
    Corndog mentioned crossovers, but I assUme your speakers aren't all that old to have component breakdowns that could affect sound, and seems to me Paradigm has some pretty decent parts to begin with.

    I think you would be really surprised by how much companies skimp on the crossovers.  It happens almost all of the time because most people aren't even aware of the innards of a speaker.  They use iron core inductors in places where an air core would be superior but would cost a few dollars more.  They use electrolytic caps which definitely compromise the sound if placed in the signal path.  Sometimes they pick the parts for size so they can mount the crossover to the back of the speaker terminals and ease manufacturing.  The ceramic resistors are ok but can still be beaten in sound quality by higher grade non-inductive resistors.

    I've transformed several pairs of speakers by following the techniques of a master speaker designer.  Even inexpensive speakers can benefit greatly by improving the crossovers.  If you consider the speaker as one of the most important components in the chain (because ultimately that's what you're listening to)  then the quality of the filter on each driver is just as important.

    A buddy of mine took a chance on this idea and asked me to upgrade his Polk towers.  I emailed Polk for the crossover schematic and found it had been updated several times by the factory.

    Turns out in each of my friend's cabinets was a different version of the crossover!  Here's one of them.



    They chose the parts strictly for size.  There's about $3-5 in parts there in a $200 speaker.  I got much better parts with tighter tolerances from Erse.  I wired them point to point and hot glued them together.



    For around $30-40 per speaker the new filter dramatically changed the sound for the better.  Bigger soundstage, tighter and more accurate bass, and better power handling.  My friend said he didn't have to turn it up as loud to understand vocals.  Even just upgrading the caps alone would give an easy to notice improvement in sound.  About the only downside is that it takes some homework and maybe trial and error to find caps that compliment the drivers of a given speaker.

    Digdug

    Posts : 18
    Join date : 2012-10-05

    Re: SP14 or a second ST120

    Post by Digdug on Fri Feb 21, 2014 1:12 pm

    Thanks for all of the information on the crossover upgrades.

    I asked the speaker manufacturer about biamping with different amps one SS, one tube (horizontal biamping) and they said it could damage the speakers.

    sKiZo

    Posts : 1285
    Join date : 2013-04-01
    Location : Michigan USA

    Re: SP14 or a second ST120

    Post by sKiZo on Fri Feb 21, 2014 2:12 pm

    That's strange ... I'd expect a crossover that's setup for bi-amping would totally isolate each section so it wouldn't matter what you use to power them up. Do yours have a removable bridge to accomplish that?

    Even stranger to have a tech support team that actually gets back to you.  tongue 

    On a related note, do they have any power recommendations for each section? Once again, it takes a LOT more power to drive bass properly, so you should (theoretically) be able to go with a smaller amp for the high drivers.

    Not that I'm trying to talk you out of going all tube, all the time, but I'd think you'd be able to at least test whether bi-amping is your particular cup of tea with an SS amp you might have laying about ...

    Corndog >> I see your point on the crossovers, but at $1800 each, I'd expect the Paradigm's to be a bit above that sort of encheapening ... then again, hard to tell without looking inside.

    PS ... here's the 4way crossovers in my McIntosh XR16's ... they look all right to me ... from what I understand, each coil is custom wrapped for that particular box ... not sure how I'd improve on that, but I'm open to suggestions.


    Digdug

    Posts : 18
    Join date : 2012-10-05

    Re: SP14 or a second ST120

    Post by Digdug on Fri Feb 21, 2014 4:22 pm

    Yes, they do have a removable bridge. You never know, the guy who emailed me back from Paradigm may not have been certain and so to play it safe, just told me not to biamp that way.

    Of course, I'd like to keep things all tube, but it would be fun to try out biamping with the SS...

    corndog71

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    Re: SP14 or a second ST120

    Post by corndog71 on Fri Feb 21, 2014 4:48 pm

    I can see there may be an issue of loudness especially if there are power differences between the upper and lower sections.  Of course you don't know if it's going to work until you try it.  It may not sound bad at all.  I would put the tubes on the tweeter/mid circuit and leave the solid state amp for the bass region.  

    When I had biwirable speakers I did lots of experiments with them.

    For biwring leave the negative side jumper in place.  (Better yet use a heavy guage solid core piece of copper wire instead of the thin brass ones that came with the speaker.) In fact using wire for jumpers is better if you don't separate the sections.

    Don't do this for biamping!  

    Some speaker designers think the separation of filters is unnecessary and ultimately a marketing gimmick.  But hey, they're fun to experiment with, right?  Question

    Digdug

    Posts : 18
    Join date : 2012-10-05

    Re: SP14 or a second ST120

    Post by Digdug on Fri Feb 21, 2014 5:06 pm

    On these Paradigms the tech person told me "The top binding posts on the Studio 100 v5 are for the tweeter alone while the bottom set is for the rest of the speakers"

    corndog71

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    Re: SP14 or a second ST120

    Post by corndog71 on Fri Feb 21, 2014 6:08 pm

    Ah, that's different. I can see why they wouldn't recommend biamping then. That tweeter can probably only handle so much power. It makes it all the weirder that they would have separate connectors. Very weird.

    tubes4hifi
    Admin

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    Join date : 2008-11-30

    Re: SP14 or a second ST120

    Post by tubes4hifi on Tue Feb 25, 2014 2:24 pm

    so both the mids and low freqs are on the same input, with the tweeter separate. So definitely go all tube. Even maybe an ST35 for the tweeter end.
    Put a volume control on ONE of the amps (probably the tweeter) and then use the dual outputs of an SP12 or SP14 to drive both amps.

    pmarcin

    Posts : 131
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    Re: SP14 or a second ST120

    Post by pmarcin on Tue Mar 04, 2014 3:28 pm

    Corndog,

    I mentioned to Shannon at DIYtube that the Forte xovers (he has a Chorus) were chintzy, as you describe. I did an upgrade similar to yours and the improvement was significant. You might mention your experience, too.

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