Powering the RS WTMW

[kgveteran]

I was wondering if a separate thread of how we are powering the center would be helpful.With it's 4 ohm load and dual woofers, what do you guys use.It would be a nice reference that wasn't caught up in the 44 pages that now exist.

I was thinking of two amps that would suit it well.One would be one half of a Adcom GFA 555mkII.The other would be an Outlaw Audio M-200.

Since I built three centers and sit them horizontal I'l leaning towards (2) Adcoms.Kinda wish I didn't sell off the ones I had that were powering my Tumults.

As of now I use B&K ST-140's. I use three as a six channel amp for my 6.1 system.

[oxcartdriver]

I've used a Rotel 870, Crown K2, and NYAL Moscode 300. I prefer the moscode for most of the range and the crown for the lower frequencies.

[BigJim_inFLA]

I'm powering mine with an Outlaw 7125.

[rumatt]

I'm powering mine with an Outlaw 7125.

I have the same amp. What else are you powering it with, and how's it do?

[chasw98]

I'm using an Earthquake Cinenova Grande X 3. Rated 600 into 4 ohms. Very quiet, lots of headroom.

Chuck

[BigJim_inFLA]

I have the same amp. What else are you powering it with, and how's it do?

I like the amp quite a bit. It is powering the center, Modula MT surrounds, and Klipsch Chorus II mains until my TMWW's are completed. I do live in an aprtment so I don't listen at high SPL very often so I can't comment on it's performance in that regard. At moderate levels the sound is very clean.

[Jim Holtz]

About any good amp with 125 watts and up should be just fine. If you don't mind going used, the Marantz MA500 is a very clean little monoblock that can be bought for $125 - $150. I have used one on my center channel for several years and have been very happy with it. Audio Refinement is another excellent brand that sounds great. They can also be found used for much, much less than they cost new. The older Haflers are also a great buy, particularly if you can find one with Musical Concepts mods. It's very high end sound at that point. Musical Design is another great choice if you can find one. Go to Audiogon and search a bit.

You probably already know this but the B&K ST140's were only rated for 8 ohms and fall flat with a 4 ohm load. Very nice sounding amps but not good for low impedance loads.

HTH

Jim

I was wondering if a separate thread of how we are powering the center would be helpful.With it's 4 ohm load and dual woofers, what do you guys use.It would be a nice reference that wasn't caught up in the 44 pages that now exist.

I was thinking of two amps that would suit it well.One would be one half of a Adcom GFA 555mkII.The other would be an Outlaw Audio M-200.

Since I built three centers and sit them horizontal I'l leaning towards (2) Adcoms.Kinda wish I didn't sell off the ones I had that were powering my Tumults.

As of now I use B&K ST-140's. I use three as a six channel amp for my 6.1 system.

[dynamowhum]

Powering mine quite well with a panasonic xr 57 thank you.

[kgveteran]

The outlaws M-200 is in my sights.They rate it at 300watts into 4 0ohms.

[kgveteran]

"You probably already know this but the B&K ST140's were only rated for 8 ohms and fall flat with a 4 ohm load. Very nice sounding amps but not good for low impedance loads."


There are only two outputs per side.I think it would make a nice mono if B&K still did work like that , but the old timers are gone and the new tech guys don't have the time.

Three M-200 Outlaws will do fine.

[Edge540]

I'm using an Outlaw 755 on my WWMT mains and WTMW center. No complaints from amp so far.

[kgveteran]

Well, the first one is on the way!

[ssabripo]

I'm also using the Cinenova Grande 5chnl amp, 300Wx4......very powerful, lots of headroom, and most importantly, pure silence and borderline "cool"

[kgveteran]

Ya, the RS threeway dual woofer needs a bit more control than my little B&K's.The Outlaw should do much better at controling it and give me a bit more headroom.

[crackyflipside]

Now, I may not be as enlightened as some of you old-timers here on the board :P

But wouldn't a good receiver, let's say outputting like 125wpc, be enough to power a single tower (especially if speaker is set to small). I really don't understand the logic behind putting 500-600 watts into one single tower speaker if you are going to end up running it crossed at 60hz with your sub (which basically takes out the so-called 'power robbing' bass frequencies)

Tell me if I got this wrong or if I am thinking the wrong way, BUT, let's say you have 1w of super clean power, theoretically you have like, let's say, the tower runs 88db sensitivity. So you would reach 105db with under 100w?

Is it really necessary to be pumping 500w into the tower? Or is it just the 'more gas in the tank' concept?

[kgveteran]

Now, I may not be as enlightened as some of you old-timers here on the board :P

But wouldn't a good receiver, let's say outputting like 125wpc, be enough to power a single tower (especially if speaker is set to small). I really don't understand the logic behind putting 500-600 watts into one single tower speaker if you are going to end up running it crossed at 60hz with your sub (which basically takes out the so-called 'power robbing' bass frequencies)

Tell me if I got this wrong or if I am thinking the wrong way, BUT, let's say you have 1w of super clean power, theoretically you have like, let's say, the tower runs 88db sensitivity. So you would reach 105db with under 100w?

Is it really necessary to be pumping 500w into the tower? Or is it just the 'more gas in the tank' concept?

It's about headroom (gas in the tank).The more power you have the better the amp is able to control the speaker.The better it controls the speaker the better it sounds(if it's a good sounding amp ).

I've learned that over these years overkill aways sounds better than underkill.These little centers sound great, but my little two transister B&K couldn't cut it.So why bump the power up a little bit, when I can triple it and remove a weak link.I built these monitors so i won't be bulding anymore any time soon.

Why have four 15" subs.Linear reproduction.The more you have the less each one works and the better it sounds.Overkill is now a way of life for me in this hobby.

KG

[Dennis H]

Tell me if I got this wrong or if I am thinking the wrong way, BUT, let's say you have 1w of super clean power, theoretically you have like, let's say, the tower runs 88db sensitivity. So you would reach 105db with under 100w?

You have to remember that those numbers are at 1 meter. -6dB at 2 meters, -12 dB at 4 meters. So, your 100 watts (into 8 ohms but this is a 4-ohm speaker so it's really 200 watts into 4 ohms) is giving you 108 - 12 = 96dB at 4 meters. Pretty loud but nowhere close to 'reference' level.

[kgveteran]

You have to remember that those numbers are at 1 meter. -6dB at 2 meters, -12 dB at 4 meters. So, your 100 watts (into 8 ohms but this is a 4-ohm speaker so it's really 200 watts into 4 ohms) is giving you 108 - 12 = 96dB at 4 meters. Pretty loud but nowhere close to 'reference' level.

And if you want ,"Gas in the tank", you better get it at least 20% above reference to get that comfortable feel to it.Thats why 300watts should get me 20% above reference.I think arty:

Keeping in mind I rarely get it above 85-90db.

[kgveteran]

Crackyflipside,
Happy 2nd post!

KG

[chasw98]

Hey cracky!
It's about headroom as everyone says, but you have to remember that with an amp rated 600 watts, 118 db S/N ratio, and .0001% distortion at full output, and then you run it at 1/10 speed, the noise floor is almost nonexistant along with all the other factors. What you end up with an amp that is easily reproducing the demand you place on it with very clean operation. You can see where your 125 watt receiver running at 50 or 75% capacity will not be as clean as an amp that has triple or quadruple the power and is only using 25% of its capacity. You really need to come by the house and here the difference soon.

Chuck

PS: Good to see you over here in this neck of the woods :T

[WillyD]

These little centers

:rofl:

[cobbpa]

Does the S/N ratio rise and distortion decrease in a linear fashion? I.e., using Chuck's example, running at 10% means the distortion is at only 10% of full output?

Edit: This was mostly answered in another thread...so ignore at your leisure, if you'd rather.

[kgveteran]

:rofl:

I know . Compared to the Ascends I was working with yesterday, these things are monsters.

I'm not sure if it's the number of XO components, or number of drivers or the alignment&efficiency of the alignment that makes it a tough load...or just the end product resistance (which I use to think you could just measure with a multimeter ops: ).

In the end, used wisely, more power is just plain cleaner.I'm almost sure that that is the differences most hear in an amp to amp comparison.The fringe of the amps linear signal.Who knows.

[BobEllis]

IMHO, it is all about avoiding clipping. Mega-power amps generally have slightly higher distortion numbers, but usually it's down in the range where it is inaudible anyway. No, I am not saying all amps sound the same, but clip any amp and YUK!

Rather than work it from average level and add some, I suggest figuring out how much power is needed to reach your reference level + 3 dB for headroom.

If peak is 10 dB more powerful than the average it means that your amp needs to put out ten times the power. So, if you are listening at an average power around 1 watt, you need 10 watts to keep up with a 10 dB peak. Those loud "grab the remote to turn it down" explosions are probably closer to 20-30 dB above average - 100-1,000 times more powerful.

Suddenly 500W doesn't seem unreasonably large. And multi-amping makes more sense when you can use smaller amps to reach the same apparent output.

I am still working out the details of my active crossover for my WT/MW center, but it will have ~400W for the woofers and 150 each for mid and tweeter. The tweeter shouldn't need that much but it's what I have available.

[crackyflipside]

Hey cracky!
It's about headroom as everyone says, but you have to remember that with an amp rated 600 watts, 118 db S/N ratio, and .0001% distortion at full output, and then you run it at 1/10 speed, the noise floor is almost nonexistant along with all the other factors. What you end up with an amp that is easily reproducing the demand you place on it with very clean operation. You can see where your 125 watt receiver running at 50 or 75% capacity will not be as clean as an amp that has triple or quadruple the power and is only using 25% of its capacity. You really need to come by the house and here the difference soon.

Chuck

PS: Good to see you over here in this neck of the woods :T

Ahhhhh, it all makes sense now.

You know it's tough, Chuck, I really want to go to hear the seas towers but the damn house is taking up all my time. Headroom, headroom, headroom; so that's what it is all about. Next semester (starting in Jan), I have a class every Friday in Pembroke Pines so I'll have some time then to swing by your place (of course I'll try to make it earlear during like thanksgiving time to hear the speakers).

Yeah, I started here because I might as well start asking questions when I get ready to start building the Towers and MT's.

[ibilisi]

Anyone running these with DIY amps?

I'm thinking of trying to use a single AMP5 from http://www.41hz.com/ for each speaker, not a "true" biamp of course. Anyone foresee issues with this?

I would first try it on my center as a test case.

[WillyD]

ibilisi - I've been checking 41hz out for a few years. There are some discussions about their amps on DIYAudio. Certainly intriguing....

[Gray]

kgveteran did you ever get your M-200's in? How do you like them with this center?

[kgveteran]

kgveteran did you ever get your M-200's in? How do you like them with this center?

They sound great.I really needed the headroom. Great little amps!

[digital desire]

I am going with an adcom 555 II for the towers and a ma500 for the center.
Both of them from ebay.....CHEAP!
Just need the speakers....

[kgveteran]

The Adcom 555mkII is a great amp.Tons of power for mains, you will enjoy them.

[Fryguy]

I'm bi-amping my daytons with behringer A500s.

1 dayton to 1 behringer. I'm currently using just the towers however, no center.

[kgveteran]

I'm bi-amping my daytons with behringer A500s.

1 dayton to 1 behringer. I'm currently using just the towers however, no center.

Do you get a bit of buzzing out of your A500's, I do.

[Fryguy]

I get buzzing from my surrounds (which are connected to another a500, 1 surround per channel) because I'm using a shitty interconnect (different from the rest of the system).

[kgveteran]

I get buzzing from my surrounds (which are connected to another a500, 1 surround per channel) because I'm using a shitty interconnect (different from the rest of the system).

But, I use the same shitty :B interconnects that go to the Outlaw mono's and no buzzing.

I can't hear it from the seating position...so they'll probably stay.

[digital desire]

Fryguy, are ALL your amps pluged into the same mains circuit?

[speedle]

I've learned that over these years overkill aways sounds better than underkill.....Overkill is now a way of life for me in this hobby.

KG

Yes!