Best RT 12, 10, 8 for HT

stubro

marker wrote:

The 4806 and 5805 are THX Ultra II, so they ARE specked to drive 4 Ohm loads FWIW.

marker help me out here been a while since I thought about V=IR. What does this mean for the Rts? I see they are 8 Ohm rated can I get the advantage of the 4806? Do I have to have THX ultra II speakers to make this work?

stubro

Well I think I have made my decision on a receiver I am going with the Outlaw 990/7125 instead of the Denon seems to make more sense. I am leaning towards the RT8s so that should be good power for them I hope. Thanks for everyones help I am sure I will be asking more questions as I move forward.

jdhdiggs

stubro wrote:

Well I think I have made my decision on a receiver I am going with the Outlaw 990/7125 instead of the Denon seems to make more sense. I am leaning towards the RT8s so that should be good power for them I hope. Thanks for everyones help I am sure I will be asking more questions as I move forward.

Ask away with more questions...

I don't think you'll be able to be more pleased with this plan. This option also opens a few more upgrade paths to you that were not open before. (Outlaw has provided HW and SW updates in the past). This also would allow you to go LSi's or othe speaks in the future without worrying about changing out other equipment...

marker

Congrats! The 4802 is a monster AVR, but you can't go wrong with Outlaw separates either.

BIZILL

rti8's will do you right. my 110 watts do justice to them. got the svs and need nothing more.........besides a set of sda's for a separate room.

sickicw

get the Denon 2807 as it is the only one that can handle the audio from blu-ray or hd-dvd.

stubro

BIZILL wrote:

rti8's will do you right. my 110 watts do justice to them. got the svs and need nothing more.........besides a set of sda's for a separate room.

I ordered the SVS PB12-Plus shouldbe enough for my room.

disneyjoe7

I say RT12....

110w will be OK for now, sorry if my 400w turned you off a little.

sickicw

If you get the rt12s, i would get a 5 channel amp (if you dont have one already... (sorry if this was already talked about, i didnt read all of these posts)), and bi-amp them, and use the remaining channel for the center speaker. If you dont want to buy am amp, i would go with the rti6s. They will sound better than the 8s without an amp.

stubro

sickicw wrote:

If you get the rt12s, i would get a 5 channel amp (if you dont have one already... (sorry if this was already talked about, i didnt read all of these posts)), and bi-amp them, and use the remaining channel for the center speaker. If you dont want to buy am amp, i would go with the rti6s. They will sound better than the 8s without an amp.

Thanks I am getting a 125WX7 Outlaw Amp should I still bi-amp?

stubro

AS sn FYI here is what I posted on the outlaw forum on what I am going from and to.
I currently have a Yamaha DSP-A3090 older top of the line Yamaha and to be honest it has never impressed but it could be the speakers, setup etc. I am changing everything out with this build. I am wondering if I should have gone for the bigger amp? I will see how the 7125 does.Cant turn it up loud too much kids sleep above the TV room.
New system

Sony 46" LCD XBR2 <-- new
Outlaw 990/7125<-- new
Oppo 971 DVD <-- new
Xbox 360 <-- existing
SVS Sub <-- new
Belkin F60 power/surge <-- new
Polk speakers --still deciding
BDI Avion 8539 ent. center<--new
Replaytv 5080-300 gig hoping to still find a way to use this.

replacing
Yammy DSP-A3090
Kplish center, mains, and sub --not good ones
Boston Acc. surrounds
Toshiba Cinema Series SD CRT 36"

sickicw

stubro wrote:

Thanks I am getting a 125WX7 Outlaw Amp should I still bi-amp?

I would at a minimum bi amp the left and right speaker especially if you get anything bigger than a rti6 or rti8. If you get the rti12, I would no doubt bi amp them. If you get a receiver then you can also use the receiver output to drive a pair of rear speakers if needed. (EDIT, is see you are getting the 990, so forget what i said about the receiver. Also If you plan on ever getting a HD-DVD player or Blu-ray player for high definition movies, i would hold out on the 990 and get something that can support these players with a digial interface such as hdmi. This might not be important for you, however)


If you think that the 7125 is not big enough, then instead of buying one bigger amp, you might want to consider two amps. possible even two 7125s. It really depends on what speakers you get. If you go with the rtis, you have more options, but if you step up to the lsis, then you need LOTS of power.

Also consider getting a dedicated power line to your amp to reduce current compression (reduction of dynamic range).

sickicw

Oh, you know what. I just realized you are getting a Sony 46" LCD XBR2. I am actually looking at this TV right now. I am waiting to check this one out at best buy. Hopeing to get one within a month or so.

Also, have you demoed the lsi speakers? I upgrading from the rti, and they are pretty sweet, but only of you want to spend big bucks for them and for amplification. I would rather have the smallest lsi speaker than the largest rti one. I currently have the lsi9s, lsic, and a pair of rear lsi speakers. And by the way the lsi9s have some major bass for there size and sound great for two channel audio.

jdhdiggs

BI-AMPING IS NOT ADDITIVE!!! This is a VERY common mistake. People tend to think the tweeters and the woofers use the same amount of power. This is not the case. If a tweeter sees 1W it will fry! So when you are bi-amping, you are wasting all that potential power into the brick wall of the X-over. It's not just about power, you need to analyze the whol circuit in dynamics.

Additionally, If you do not remove the X-over to a line level X-over before the amps (active bi-amping), you can still drive the tweeter amp into clipping and fry the tweeter because the amp is still trying to set the rail voltage to 100V when it's only capable of producing 90V for a bass passage that this part of the speaker won't even play.

In reality, passive bi-amping 2 200W per channel amps gets you about 201W of effective power. The "benifit" is only from effectively bi-wiring and a good dose of placebo.

With a sub, 125W will be DEAFENING!!! I doubt you will ever even use more than 20W on a speaker like the 8.

sickicw

jdhdiggs wrote:

BI-AMPING IS NOT ADDITIVE!!! This is a VERY common mistake. People tend to think the tweeters and the woofers use the same amount of power. This is not the case. If a tweeter sees 1W it will fry! So when you are bi-amping, you are wasting all that potential power into the brick wall of the X-over. It's not just about power, you need to analyze the whol circuit in dynamics.

Additionally, If you do not remove the X-over to a line level X-over before the amps (active bi-amping), you can still drive the tweeter amp into clipping and fry the tweeter because the amp is still trying to set the rail voltage to 100V when it's only capable of producing 90V for a bass passage that this part of the speaker won't even play.

In reality, passive bi-amping 2 200W per channel amps gets you about 201W of effective power. The "benifit" is only from effectively bi-wiring and a good dose of placebo.

With a sub, 125W will be DEAFENING!!! I doubt you will ever even use more than 20W on a speaker like the 8.

Wow, I'm not even going to try to comment on this. I am just giving advice that I think will work well and works very well in my setup. Also I have studied power circuits before (I do have a MS in Engineering) and anything that can add more current (I'm not talking about power here) to your system will help the dynamic range. The difference may not be huge using the rti speakers, but if you step up to the lsi line, the difference is day and night.

sickicw

Edit

jdhdiggs

Are you an EE? Obviously not... How were your circuits grades? Have you studies how an X-over works? You are not adding more current, the X-over blocks it, its resitance below the X-over point becomes infinate so how are you supplying more current... The current is needed in the low end and it is still limited to one amp... as in the two binding posts are no longer connected. I would strongly suggest you go review your EE coursework on dynamic circuits. In DC cases you are correct, unfortunately this is not DC. I mean, since your an "engineer" explain how providing more current to the tweeter is going to help out the bass?

FYI: Each octave you drop requires a doubling of power to reach the same dB level. You can see that the tweets need no power compared to the woofs.

I love when people bring up their education when they have no idea of they are talking with...

stubro

Ok well that was fun I have an ME degree so I didnt listen much in my circuits class Now if we talk gears.

jd question given my new confifuration with the 990/7125 which front do you recomend? Also surrounds? I have ordered the SVS PB12 PLus sub.
Thanks.

stubro

sickicw wrote:

Oh, you know what. I just realized you are getting a Sony 46" LCD XBR2. I am actually looking at this TV right now. I am waiting to check this one out at best buy. Hopeing to get one within a month or so.

Also, have you demoed the lsi speakers? I upgrading from the rti, and they are pretty sweet, but only of you want to spend big bucks for them and for amplification. I would rather have the smallest lsi speaker than the largest rti one. I currently have the lsi9s, lsic, and a pair of rear lsi speakers. And by the way the lsi9s have some major bass for there size and sound great for two channel audio.

A little off topic but hey why not. I did a lot of reseach on the right TVand i was going to get the A2000 SXRD but the reviews from people that have it are not good. I dont want the SXRD with the speaker ears so I went with the LCD for my current house. Next house projector or more likely 70" SXRD sans speakers. BTW check out the AVSforum for the LCD XBR thread it is getting good reviews.

sickicw

jdhdiggs wrote:

Are you an EE? Obviously not... ...I would strongly suggest you go review your EE coursework on dynamic circuits.

Hmmmmm, if I am not an EE, why would I have EE coursework?

jdhdiggs wrote:

You are not adding more current, the X-over blocks it, its resitance below the X-over point becomes infinate so how are you supplying more current

So you are saying there is no current in the tweeter circuit because the x-over blocks it? yea ok.

jdhdiggs wrote:

I mean, since your an "engineer" explain how providing more current to the tweeter is going to help out the bass?

Hmmm, I never said anything about bass. I am talking about dynamic range. This includes dynamic range of the high frequencies as well.

jdhdiggs wrote:

FYI: Each octave you drop requires a doubling of power to reach the same dB level. You can see that the tweets need no power compared to the woofs.

Where did you come up with this number? On average, the woofer may take more power than the tweeter, but this is not always true. What about the case where the sensitivity of a tweeter is 80db, but the main woofer is around 96bd?

jdhdiggs wrote:

I love when people bring up their education when they have no idea of they are talking with...

I (and I am sure other people) only bring it up to show that I (we) are not an idiot(s). Now you might have a dozen PhDs, own your own speaker company, or whatever other credentials you have, but that does not mean you are going to convince me that be bi-amping is only a “good dose of placebo”. Sorry it is not going to happen.

EDIT: I am done with this convesation, and i am sure stubro is sick of reading about it as well.

jdhdiggs

Stubro: ME here as well, although I worked as an EE for TI for about 4 years as I tried to move to their business side, got sick of that crap and left to supply chain cosulting. ME's Rock!!! Allows you to do damn near anything. BTW, that means you probably followed that conversation so congrats!

Anyway, I would go ahead and straight amp the entire setup, use 1 channel each for each speaker. With the 990, you can set each speakers X-over to the sub independently. I would suggest to go one octive higher than the -3dB point or 80 Hz, whichever is lower for HT. For 2-channel, I would set the FR/FL to 1/2 Octave above the 3dB point. Since you are using ported speakers, you'll need to set the x-over point higher than the -3dB point as a ported enclosure drops off much quicker than the slope of the sub's filter picks up the sound so if you set the x-over point right at the -3dB point, the port and the xover make the drop off too steep and you end up with a dip in the spectrum. Hope that makes sense.

If by speakers, I'd still stick with the 8's. Try them both out if possible in your setup, but I'd guess the 8's would blend a bit better with the other speakers. I would rather go with the 8's and CSi5/FXi5 (or RTi6's for SR/SL) then the 12's and CSi3/FXi3's. But I don't know your budget. In the end, I don't know your budget or preference or habits... I just recommended what I would do.

The thing with the 12's needing 400W of power is accurate and not. The amp needs to have an adequate slew rate (how fast can it change the signal) and damping rate (how much force or control does the amp have against ringing) to get really nice bass and performance from a bass hungry speaker. Typically, these values are increased as the power rating on an amp is increased. Those outlaws would treat the 12's just fine. You may get more out of them with a bigger amp, but I doubt it would be a night and day difference as it would be moving from an AVR to 400W

Sick
Yup, can't help the ignorant, but I can help prevent the spread of mis-information...

I'll cover you "statements"

If you were an EE you would have stated that, not I have an MS in engineering... Most engineers have to take at least circuits 1 and/or physics courses that cover E&M. Gee, I wonder why I know that??? I hope your not an IE... Yikes...

Yes, there is current in a tweeter, measure in milli-amps... Not a big deal when you are talking about an amp capable of delivering 10A or more

Dynamic range is the same as before. I have no idea why anyone would think that this would be different with 2 amps instead of 1.

As far as drop an octive, double the power. Do the research.. Mind you that is accoustic power. Typically tweeters are much, MUCH more efficient than any bass driver. You've essentially proven your ignorance at this point.

As for the last part, generally the "education" card comes out as the last resort of someone who believes something but can't prove it. A kind of "See, I am smart, listen to me!!!" If your argument had merits, you wouldn't need it.

If bi-amping were so great, why do high-end amplifier manufacturers make quad amps just for this purpose? It would be much easier to make 2 200W amps than 1 400W. Is it just possible that they might know something you don't?

I'm glad you've decided that this conversation is over and made up stubro's mind as well... :rolleyes:

If you are still listening, bridge your amps and run one per side and report back. BTW, I never said there was no benifit, just minimal. Far below what people "think" they are hearing.

Willow

Wow ok, I am no EE, IE, PHD. I am a ME, meaning myself, My Ears....
I have the 8 with a csi3 (do to size of cabinet) and 4's for rears. I couldn't be happier, they are currently powered by my HK 335. Am I 100% happy? NO I do plan on buying an amp either a 3ch or 5ch heck maybe even a broken 5 ch;) to power my main 3s. As far as how many watts...well depends on who makes the amp. I am eyeing outlaw as well the 125wpc.

JD I am not even going to debate the bi-amping with you cause I know jack about that. For a while there was always talk about biamping, for some reason recently I have heard buy a Man's amp and don't biamp.

What I can say is I have tried biwiring, mind you only with my AVR and noticed nothing. When I do buy an amp I will not bi-amp nor will I bi-wire, will run just as is.

To get back to the main topic, I would say get the 8s a good sub, the 5 or 3 and 4-6 as rears. Get a good AVR and an amp, you'll be laughing !

jdhdiggs

Nothing wrong with that Willow, I'd agree with everything you wrote 100%

BTW, I do biamp, not for more power, but because my tubes sound so much better on the highs than the SS, but don't have the power to drive down low. Of course I'm active bi-amping so neither the tubes and the SS amps produce the whole frequency range. I'll be trying an active tri-amp here in a bit but I need to set up the line level filters and ensure I won't blow up anything.

Willow

alright so using a Y from AVR to AMP is passive Bi-amping and not suggested ? is this right? boy this is foreign to me ? I did not know there was passive and active bi-amping...heck now you throw in tri amping?

zombie boy 2000

btw excellent post Willow

jdhdiggs

One problem you may have is that the gain may be different between the AVR and an amp. In my house I have 6 different amps (2AVR's, 4 amps) Each has different gains. For example, if I play my Adcom 565 with my knight monos, all I hear are highs from the knights... The bass is gone. The knights gain is about ~9-10 dB hotter than the adcom's. Meanwhile, the gain difference between the countrpoint and knights is ~1dB which I find acceptable. A mistake a lot of people make is that the gains will be close but not quite the same so the sound is different. They think the different sound is due to the added power when in fact you've changes the response curve of your speaker. If you like the new sound, cool. It doesn't hurt to try, just don't fool yourself thinking that you are getting tons of free power.

One good side affect of biamping with a receiver if you can only do the front two speakers is that the bass power needed by FR and FL is offloaded from the AVR leaving more of the transformers power output to be available to the other AVR channels. Addtionally, the timbre should match very well as most auditory timbre clues come from the tweeter which would be driven with the same amp configuration all the way around.

Passive bi-amping is where you send the whole signal to both amps where the signal is amplified and sent to the speaker wher x-overs direct the sound to different drivers.

Active bi-amping removes the X-over from the speaker and moves it to before the amp. In this configuration, each amp only amplifies the part of the signal that the particular driver it's feeding will use.

Summary:

Passive:
Pre => Amp => Speaker => X-over => Driver

Active:
Pre => X-over =>Amp => Speaker => Driver

As for tri-amping, the knight mono's, counterpoint, and adcom all have very different sounds and qualities. The maggies have three drivers and external x-overs.. Sounds like a match! The knights to the ribbon tweeter, the counterpoint to the mids, and Adcom to the bass panel.

Willow

I'll leave bi-tri-passive-active amping to you ! When I get my amp it'll be one IC from pre-pro to amp and one speaker cable....for the time being.

sickicw

OK, I hate getting into these type of arguments, but I will address a few things you asked about.

I studied computer and electronics engr (including power electronics) for undergraduate and software and systems engr for grad school.

Dynamic range compression is a result of your amp not being able to supply the correct amount of current fast enough for high dynamic signals. Now there is usually some bottleneck in your system that will limit the high instantaneous current from being delivered. This bottleneck can be the power cord or speaker wire, wall impedance, too small of capacitors or transformer in the amp, a power supply that isn’t quite up to snuff, speakers that are too low of impedance for your amp to keep up with the current, an amp that doesn’t “double down” (that is double the power as the speaker impedance is halfed).….

All of these reasons pretty much boils down to one fact. Some amps can’t supply the correct current when needed. When this happens, the voltage will drop and your music will not sound as dynamic.

My solution to this problem was to bi amp my speakers. My speakers average about 4 ohms and can dip down to about 2 ohms. Now when I bi-amp them, it increases the average impedance of each speaker driver(s). By doing this I am allowing my amp(s) to have an easier time supplying the instantaneous current needed to correctly drive the dynamic signals (voltages) to my speakers without any signal (voltage) drop.

Of course a “better” solution that you might offer me would be to buy an $8000 Krell amp that could keep up with the current demands, but guess what. I can't afford to spend that much money. So therefore, I do the best that I can with what I have, and I promise you bi-amping (at least on the lsi speakers) works great.

jdhdiggs

So you aren't an EE and never worked as one, and only have only a very basic understanding of amplifier circuits from some undergrad courses you took sometime ago. Net: You're a software engineer. Some errors:

First off, audio frequencies are not high frequency in the electronics world and are easily handled by transistors in SS amps.
Second of all, your talking slew rate, not current when your talking about dynamic range compression, not current delivery. Your entire description of an amplifier is wrong. (Audio amps act like a voltage source, not an amperage sources)

Since the resistance of a speaker is DYNAMIC, both the upper and lower binding posts have the same resistance as if they were combined together for any given frequency. You keep thinking the circuits are DC and V=IR is all you need to worry about. Guess what? that spot where it goes to 2Ohms, it still does, and you still only have the power of the one channel on one amp to play that frequency.

Besides, nothing you mention shows any merit of having one amplifier run the top of the speakers and one running the bottom. The fact is, unless you run white noise through the speakers, you gain no practical advantage running a biamp setup. At most you are gaining an effective 1-2W which in a 100W amp results in far less than a 0.3dB gain in volume. Congrats, you doubled your cost for 0.3dB of headroom. You would be better served running the amps bridged and one per channel.

Edit for Examples:

Case 1: One amplifier, one signal ~75Hz=
One amp pushing a near infinate resistance in parrallel with one 4Ohm resistor. What is the net resistance the amp sees?

Case 2: Two amplifiers, on signal ~75Hz
One amp seeing a near infinate resistance
Second amp seeing 4Ohm resistance

How much does the second amp help in case 2 versus case 1

Second example: Two tones 16kHz and one at 62.5Hz (8 Octives down) and the system is 92 dB efficient at 1khz. The signal tells the system to play each tone at 92 dB. Assuming both drivers are equaly efficient, what is the power to each?

Ans: Tweet gets 0.0625 W and the woofs/mids get 16W Tweeter power is 0.4% of the total output of the amp.

I would suggest that this is of minimal benifit to seperate the two sources of power to offset the 0.4% drain. You could say that you are helping out the tweeter but the fact is that the tweeter only amp is still trying to reproduce all of the same sounds as the one driving the woofer, just without the power drain. Not much benifit there either.

As I said before, there isn't NO benifit to bi-amping but rather you aren't doubling your effective power or benifitting yourself that greatly by doing it. Instead of spending the money on 2 amps, buy one at twice the cost and have more power and better performance accross the board.

Willow

zombie boy 2000 wrote:

btw excellent post Willow

thanks !