2 Channel Amp for Studio 100's. (1 Viewer)

[Mike_T_]

I've been trying to figure this out a bit. If I bi-amp my mains to the same amp, what I don't understand is how all 4 channels of power can go to the mains? I have my amp hooked up to the Rotel with lines running from the L/R, L/R surrounds, and center.
If I listen to let's say, 2 channel stereo, why would the rotel send the power from the L/R surrounds outputs to the Mains? There is no signal..right?

If I have a Y-splitter, I have the male ends going into two seperate amp channels on the Rotel for one speaker, then I only have 1 input (female) to connect the 4 speaker wires too from the speaker iteself?
Sorry I'm such an idiot here! I just don't understand how the Left and Right rear outputs to my Amp will suddenly be sending information to my Mains just because I hooked them up from the amp to the speaker? I feel like because the Sherbourn has 5 monoblock channels, it's just not going to 'share' power to the mains like it could on other amps.

Again, I apologize for my ignorance. Thanks for your patience!

 

[Chas_T]

Mike,

I have the configuration that Charles G. refers to in his post with the Sherbourn in a 5.1 system.

The amps I am currently using are the 5/1500A for 3 speaker channels (Front Left speaker - 200 x 2 - Center 200 x 1 - Front Right speaker - 200 x 2) and a Modial 8002/ 2 channel amp (Left Rear - Right Rear) for the next 2 channels. This takes care of a 5.1 system.

You have five channels on the Sherbourn, all monoblocks within one container. Two of those mono blocks are for the Front Left. Two are for the Front Right. One for the center.

The connections are to take 2 sets of speaker wire and connect it to the 100's. There are four binding posts on the rear of the 100's. You remove the plate that connects the two posts, wire it up accordingly and then connect them to the first two speaker channels on the Shebourn amp. Lets use speaker 1 and 2 as an example on the back of the amp. Just look at the manual.

The next process is to either use balanced or rca connectors and insert them into the Sherbourn's amp's input's. Again, Channel 1 and 2. One RCA connector wire coming from channel one and one from channel two.

The next step is take those two cables and connect them to your pre-pro/preouts. You take a "Y" Splitter and connect the single connection end and insert it into the pre-pro Left Front. Then run the rca/balanced cable's from your amp to those two connectors.

Just repeat the same process with the other front channel. There will be one channel left on the Sherbourn and use that for your Center. This connection will supply power to your front channels, Left Front, Center and Right Front. This method will take care of your front 3 channels.

I'm not a technical writer and a picture is worth a 1000 words. I could not come up with anything simplistic after doing a Google search. Maybe someone else can do better.

 

[Charles Gurganus]

You will be sending 200 watts to the woofer and 200 watts to the mid/tweeter in the biamp configuration. I think I did a reasonable job of explaining the routine in my previous post but I will try to break it down a little more.

I will use ONE front main speaker as an example...currently, you have one RCA going from your preamp to the amp. What you do is connect the female end of the Y-splitter to the male end of that same RCA cable at the amp side. So then you are left with 2 RCA male ends from the splitter. Input one into channel 1 on the amp and the other one into channel 2 of the amp (you could use any 2 amp channels as long as you keep up with the right one). OK, you ALREADY have speaker wire going from one of the mentioned amp channels to your 100 speaker, that can stay the same.

I think your statement "Sorry I'm such an idiot here! I just don't understand how the Left and Right rear outputs to my Amp will suddenly be sending information to my Mains just because I hooked them up from the amp to the speaker?" is answered in the next couple of sentences.


HOWEVER, you will need more speaker wire (preferable the same quality and length as what you already use) and connect that to the other amp channel the y-splitter was going into (of course you will have to remove the rear speaker RCA cable AND speaker wire temporaraly...you will connect those to whatever new amp you decide to add). So from the channel 2 amp you take the new speaker wire and run that to the bottom speaker post on the speakers (you should have 2 sets of speaker wire inputs on the 100 and you SHOULD remove the metal jumper that connects the 2 sets on that speaker)With this method you will be sending 400 watts to each speaker. Believe me, you won't need any more power.

Remember, this is a test to give you an idea of what 400 watts can do in a biamped speaker. So you WILL have to temporarly remove the rear RCA cables and speaker wire for this test so you can input 2 male RCA ends from the splitter into 2 amp channels on your amp. Then play some 2 channel music to hear your 100's biamped. Of course, the 5th channel would remain connected to the center channel. Then if or when you decide to add another amp, you can just connect the RCA and speaker wires you disconnected for the test to the new amp. I dunno, maybe I confused you even more.

What you need to try this is pretty simple, 2 y-splitters with one female and 2 male ends (which you use at the amp end). This basically duplicates the front main speaker signal to input into 2 seperate amp channels...then you will need 2 identical speaker runs for each front main speaker going from the 2nd channel of each y-splitter input from the amp to the bottom speaker posts.

 

[Charles Gurganus]

^=male end *=female end ----=RCA run ++++= speaker wire

Preamp preout front left speaker rca cable
^----------------^ *------^ into channel 1 on the amp
...................splitter------^ into channel 2 on the amp

Then from the amp channel 1 and 2 going to the speaker

channel 1 +++++++++++ top speaker input posts
channel 2 +++++++++++ bottom speaker input posts

Duplicate for front right main speaker using channels 3 and 4.

Maybe this crude diagram will help.

 

[Mike_T_]

EXCELLENT info guys..I think I finally got it here : )

I created a diagram in Paint, very crude..thiking I could post it here, but it looks like you can only attach web images.

Anyway, I now see how (because of the splitter) it sends the same LF and LR signal to all four monoblock sections.

If you send 200watts to the upper frequency and 200 seperate watts to the LF of the bi-amped/bi-wired speakers..is it a FULL 400wpc?

 

[Kevin Farley]

I don't even know if it's possible to get a 300-350wpc amp for less then $2000.

Hey Mike! Remember the Mackies I was talking about? how 'bout 500 W/C for $999.00???
http://www.mackie.com/sr/m2600/index.html
http://www.brookmays.com/prod_disp.asp?itemnum=M2600

Mackies are known for being very musical pro amps...

 

[Mike_T_]

That's classic, I thought you were talking about Macintosh amps! I've never heard of Mackie, but I'll definately check them out..Thanks!

 

[Ron_L]

Mackie professional amps are low in quality.

QSC Mx-1500a will handle the job no problem.

350watts/8ohm
500watts/4ohm
750watts/2ohm

 

[Charles Gurganus]

Just using the Sherbourn for the front 3 speakers (biamping the mains) and buying something like a used B&K amp (you would need a 3 channel but I wouldn't overlook a good deal on a 5 channel amp) would be an excellent way to go. You could even buy a new 3 channel B&K (or whatever) amp with moderate power for around $600--used you can find a similar amp in the $400 range.

In other words, you already have a very powerful amp so use it where it is needed most (biamp the mains) and get a moderate amp for the rears. I notice that at audiogon.com the B&K amps are snapped up very quickly. I saw several av5000, av6000 and ST1430 amps all sold but there where some Parasound amps available.

 

[Mike_T_]

Charles, I think that's starting to sound like a plan. Of course, only if I really notice a difference with the Studio's from 200wpc to 400wpc.
At the very least, it will be fun to bi-wire and bi-amp everything tonight!

Thanks again for all the help!

 

[Chas_T]

Mike.. Let us know what you thoughts are on the passive bi-amping. I am curious what your impressions are, good, bad or indifferent.

CT..

 

[Mike_Gr]

Sunfire Stereo Amplifier Series II. Its a 2 channel amp rated at 325W RMS continuous into 8 ohms (650W into 4 ohms and 1300W into 2 ohms). It retails for $2595 MSRP. You can find them as low as 2K. This is an amazing amplifier that runs very cool. I found one on sale at Elegant Audio for $2,095. The link is below:

http://www.elegantaudiovideo.com/sunamp.htm

My friend powers his studio 100s with Carver Research amps....very similar to the Sunfire.

 

[Mike_T_]

Well, I tried it out last night.. WOW! I finally feel like I'm getting the most out of those speakers. At the same volume level, the bass is much much deeper, tighter and the sound is more open and expansive. I always thought 200watts would be plenty for these, but, it wasn't!
I really feel like I can turn it up without hearing any distortion or worrying about blowing a tweeter etc

THANKS for all your help! Now, I'll either get another Sherbourn or just grab a 150wpc used Parasound or something like that, for the rears etc.

 

[Charles Gurganus]

Mike, I had the same response when I biamped my NHT VT2's with the Sherbourn. They will always stay biamped now. I've used soundcity.com to buy new B&K amps (still use the ST1400 for my rear NHT vt1.2 speakers) with great success. Plus, they are REALLY easy to sell if you ever want to upgrade. Of course just getting a 3 channel Sherbourn would be nice as well.

 

[Ricky T]

Mike,

By same volume level, do you mean made a note of your prepro's volume and kept that constant for both biamped and non-biamped?

 

[Sihan Goi]

Hmmn, how come nobody mentioned the Odyssey Stratos?

 

[Mike_T_]

Ricky,

I, like most people I believe, have a pretty good idea what setting on their pre-pro or receiver is going to get your music to reference levels. For my Rotel, it's in the upper 50's to lower 60's that can get pretty loud. Last night after Bi-amping, I had the Rotel turned up to where I normally have it and noticed a not so subtle difference in sound. I could also turn it up much louder, and the music kept it's balance in sound, it never got as though the mid's were boomy, and the tweeters became fatiguing.

Essentially, I haven't done an A/B comparison with the exact same volume level. However, after listening to hundreds of hours of music on the Studio's with 200watts, I certainly noticed an improvement with bi-amping. Fair question however. I might try it out.

I think when you add more power to the Studio's, you're really going to notice a difference when you turn up the bass, and the volume. Where previously the speakers may have reached a 'limit' they can now go even farthur and shake the room with bass. They just seeem more "capable".

Also, it will really save me some money knowing the mains are taken care of with PLENTY of power, and now, I won't have to buy a powerhouse 2-3 channel amp which can get very expensive.

 

[Chas_T]

Mike:

I think when you add more power to the Studio's, you're really going to notice a difference when you turn up the bass, and the volume. Where previously the speakers may have reached a 'limit' they can now go even farthur and shake the room with bass. They just seeem more "capable".

This was a similar experience that I had when I bi-amped the Sherbourn with the Studio 100's. The extra power for THESE speakers is an asset.

The only way to find this out, is to prove it to yourself. I thought you might have the same experience as I did with the Sherbourn bi-amping, but it's nice to know that you agree with my findings.

Also, saving the money is a strong asset. So, what else are you buying for your system with that excess cash??

For what it's worth, I decided to move my 5/1500A and purchase the 7/2100 as I am attempting to cut down on rack space. It should be arriving in the next week or so, so I'll post my impressions when it arrives. Glad this worked out for you.

Charles

 

[Mike_T_]

Ahh the best part about saving money on one component, is deciding what to spend it on! At this point I'm pretty happy with it all. I'll just need one more Amp..and I THINK I'll be happy for a while.

Oh by the way, where did you "move" your 5/1500A to?

 

[Ricky T]

Mike,

Actually the prepro's volume control is NOT the right way to a/b. You need to have the same SPL reading on a radio shack sound meter; and this applies to most A vs B comparisons (dacs, preamps, etc), not just amps. Even better if you can do a blind test: someone else chooses A vs B and you, the listener, don't know which one is playing.

Don't underestimate the power of psychoacoustics. I've been there, done that many, many times.

btw, what SPL level do you listen to 2 channel music? Average/continuous and the musical peaks? How far away are your 100s from you?