Bi-Amp

bdtae5656 · March 2009

Whats a good solid amp to use on my Center/L/R-Polk Audio LSI Center and L/R-Bose cube. Something thats good but not to expensive?

tonyb · March 2009

What exactly do you have? A polk lsi center and Bose cubes as your front left and right?

Nevermind....saw it on another thread.Dude,before you go about amping the center,you need to step up and get the front 3 speakers on the same playing field.No less than the RTI line in my opinion,then find a cheap 3 channel amp.Your center will definately benefit from an amp,but it will and probably allready does,overpower your Bose.The Hk alone will not cut it for LSI's and you may do more damage to the speaker itself by underpowering it.You need to make some decisions.Spend the coin on speakers and an amp,just get an amp for the center,replace the center with an easier to drive one,or just go with Bose and get a Bose center.If you just want a cheap amp for the center,outlaw mono's are fairly cheap,but make sure your AVR has pre-outs before dropping the cash on an amp.

bdtae5656 · March 2009

tonyb wrote: »

What exactly do you have? A polk lsi center and Bose cubes as your front left and right?

Yes and my Rec is a HK AVR354 which puts out 75w/ Channel

BjornB17 · March 2009

Polk Center and Bose L/R? Okay well you're like 1/3 of the way to making sense. Splurge and get a pair of RTi8's or something on ebay for $300 or whatever they are going for.... you'll be glad you did!

Welcome to club polk!

EDIT: or if you want to match your center channel, LSi15's refurbed go for about $900 + shipping.

If you're on a tighter budget you can cell that LSI center for a pretty good chunk of money and then get RTi's and CSi for the front.

bdtae5656 · March 2009

tonyb wrote: »

What exactly do you have? A polk lsi center and Bose cubes as your front left and right?

Nevermind....saw it on another thread.Dude,before you go about amping the center,you need to step up and get the front 3 speakers on the same playing field.No less than the RTI line in my opinion,then find a cheap 3 channel amp.Your center will definately benefit from an amp,but it will and probably allready does,overpower your Bose.The Hk alone will not cut it for LSI's and you may do more damage to the speaker itself by underpowering it.You need to make some decisions.Spend the coin on speakers and an amp,just get an amp for the center,replace the center with an easier to drive one,or just go with Bose and get a Bose center.If you just want a cheap amp for the center,outlaw mono's are fairly cheap,but make sure your AVR has pre-outs before dropping the cash on an amp.

What are pre-outs??? Yeah I started with the bose and now im finally trying to build around my AVR and LSI center

Jeb85 · March 2009

I run a full LSi system from my HK AVR354 (2xLSi15s, LSi center, 2xLSi 9's), it runs a little hot when im pushing it but i have never had any problems(I Play my movies and music very loud). This reciever does have pre outs if you want to add an amp to help power your system which i really don't think you need in my own opinion.
FYI HK doesn't recommend powering 4ohm speakers like your LSi center with this AVR i asked when i bought my speakers. and i agree with Bjorn go polk all the way! you'll love the LSi's

tonyb · March 2009

Jeb85 wrote: »

I run a full LSi system from my HK AVR354 (2xLSi15s, LSi center, 2xLSi 9's), it runs a little hot when im pushing it but i have never had any problems(I Play my movies and music very loud). This reciever does have pre outs if you want to add an amp to help power your system which i really don't think you need in my own opinion.
FYI HK doesn't recommend powering 4ohm speakers like your LSi center with this AVR i asked when i bought my speakers. and i agree with Bjorn go polk all the way! you'll love the LSi's

You guys kill me.....running a complete lsi system on a Hk receiver?How much coin did you drop on those nice speakers?? Since every other thread here is about powering lsi's,you can't say your not informed.Thing is,when underpowering speakers,such as you are doing,your doing damage to them.Will they still play? Of coarse they will,but you will not realize what damage is done untill it's too late.Maybe some people don't mind shelling out the coin to fix or replace speakers,I dunno,but please be aware of power needs with anything you buy.

Just a side note-you say that HK doesn't recommend powering 4 ohm speakers....yet you continue to go out and purchase 5 of them to run off an HK and advise others to do so.When your speakers or avr crap out,will it be because Polk makes poor quality speakers? Or HK quality sucks? You may get a kick out of dropping the coin every so often to replace gear gone bad,but please refrain from advising others to do so.

Marty913 · March 2009

bdtae5656 wrote: »

What are pre-outs??? Yeah I started with the bose and now im finally trying to build around my AVR and LSI center

bdtae5656, as you probably know, a receiver is really a processor and a set of amplifiers combined into one box. The pre-outs on a receiver let you use the output of the processor part and add separate amplifiers (bypass using the built-in ones) to get more power. Some receivers do not have pre-outs, some do. Your HK has pre-outs and their usage potential should be documented in your manual.

I think your best approach (at least your most inexpensive) may be something along the lines of what BjornB17 was suggesting. You center is absolutely great but building a system around it will ultimately require you to replace your receiver or add amplifier(s) plus replace all of the Bose. Since your receiver is relatively current, it might be better to start with the speaker selection. I'm not sure you can build around your center and the receiver as you indicated you wanted to. It may be one or the other unless you want to add amplifiers. I'm assuming you have just the Polk center but that's a little unclear from the post. I do think it's admirable you want to improve your system and there is a lot of good help here.

Do you have a budget??

Jeb85 · March 2009

tonyb.... HK and Polk LSi are both very good brands and HK advised me that it was not recommended but the avr will handle them. now you seem to know how well each of these brands work together, do you have a system set up by them or did you fork out the cash for an external amp? or are you just going by what everyone else says?
just a question becuase you don't know if you don't know, and well i do know. i might not have as many post as you but that doesn't mean i don't know what im talking about.
as for bdtae5656 you don't need to change any of your speakers, Bose is a great brand as well and your LSi center will sound good with them.

Just a side note. tonyb I am trying to give my opinion if you have a different opinion post it, but if you don't know the system then don't bash it. Eveyone has there own opinion. I am going to be buying a rotel rmb 1565 to go with my AVR, but its not in my budget yet, and HK's word was that their AVR354 will power the speakers but the 4ohm load will make the reciever run hotter than normal(not burn out).

raidersrule76 · March 2009

guys guys guys, can't we all just get along!

BlueFox · March 2009

tonyb wrote: »

....you can't say your not informed.Thing is,when underpowering speakers,such as you are doing,your doing damage to them.Will they still play? Of coarse they will,but you will not realize what damage is done untill it's too late.

Underpowering a speaker damages it? Sorry, but that is just wrong. Clipping a speaker can damage it, but pumping 1W into a speaker will not hurt it.

I hope what you meant to say was using a low power, low end amp, AVR, receiver, etc., and playing it at max volume has the potential to damage a speaker. Any speaker.

I personally ran 4 LSi15s, and an LSiC with a Denon 3805 and a Sony 5000ES for two years with no problem. After upgrading to a Sunfire TGA5400 the speakers still work, and sound better.

Systems · March 2009

BlueFox wrote: »

Underpowering a speaker damages it? Sorry, but that is just wrong. Clipping a speaker can damage it, but pumping 1W into a speaker will not hurt it.

I think he may have meant that when using a smaller amp you run a greater the risk of it clipping a good percentage of the time ,thus the potential of damaging the tweeters delicate voice coils.

Marty913 · March 2009

tonyb wrote: »

Thing is,when underpowering speakers,such as you are doing,your doing damage to them.Will they still play? Of coarse they will,but you will not realize what damage is done untill it's too late.Maybe some people don't mind shelling out the coin to fix or replace speakers,I dunno,but please be aware of power needs with anything you buy.

BlueFox wrote: »

I hope what you meant to say was using a low power, low end amp, AVR, receiver, etc., and playing it at max volume has the potential to damage a speaker. Any speaker.

I'm pretty sure tonyb was referring to Jeb85's comment that "he runs his system very loud" and "the HK runs hotter than normal" which would certainly imply he isn't putting 1W into the speaker. That being the case, I agree with tonyb. By the way, I do have an HK and have driven Polk SDA's at moderate volume for short periods of time. I would NOT recommend it.

Bose cubes are not good speakers. If you can find a few members of the forum out of the thousands or so that think they are, let me know.

bdtae5656 · March 2009

Marty913 wrote: »

bdtae5656, as you probably know, a receiver is really a processor and a set of amplifiers combined into one box. The pre-outs on a receiver let you use the output of the processor part and add separate amplifiers (bypass using the built-in ones) to get more power. Some receivers do not have pre-outs, some do. Your HK has pre-outs and their usage potential should be documented in your manual.

I think your best approach (at least your most inexpensive) may be something along the lines of what BjornB17 was suggesting. You center is absolutely great but building a system around it will ultimately require you to replace your receiver or add amplifier(s) plus replace all of the Bose. Since your receiver is relatively current, it might be better to start with the speaker selection. I'm not sure you can build around your center and the receiver as you indicated you wanted to. It may be one or the other unless you want to add amplifiers. I'm assuming you have just the Polk center but that's a little unclear from the post. I do think it's admirable you want to improve your system and there is a lot of good help here.

Do you have a budget??

Im looking to buy a 3 channel amp but dont really know where to start looking for one....I dont want to pay over 400 for one. As far as the set up I have...I started with the bose system and the HK...I recently bought a Sony xbr4 52' along with the LSI C, then bought a new surge protecter-Panamax 5100. I noticed that the LSI C was over powering the Bose and then thought I need to find some good floor speakers.....But I didnt realize that I needed more juice until joining this site. What do you think? Please explain the wiring of the amp to the speakers and AVR other then the RCA cables going into the pre-outs.
Thanks,

Marty913 · March 2009

bdtae5656 wrote: »

Im looking to buy a 3 channel amp but dont really know where to start looking for one....I dont want to pay over 400 for one. As far as the set up I have...I started with the bose system and the HK...I recently bought a Sony xbr4 52' along with the LSI C, then bought a new surge protecter-Panamax 5100. I noticed that the LSI C was over powering the Bose and then thought I need to find some good floor speakers.....But I didnt realize that I needed more juice until joining this site. What do you think? Please explain the wiring of the amp to the speakers and AVR other then the RCA cables going into the pre-outs.
Thanks,

OK, Im going to make some assumptions here so correct me or ignore what I say if the assumptions are wrong. Please keep in mind there are multiple considerations to be made depending on what speakers you get and what amp. You buy, new or used, replacing the LSI center, etc. My assumptions are:

You are keeping the LSI center
You will replace the Front left/right Bose with speakers that more closely match the LSI Center (either LSI or otherwise but obviously LSI would be the perfect match) OR you will replace the LSI Center and the Bose fronts with three other speakers that do match.
You will keep whatever surrounds speakers you have or replace them but regardless you will power them with your current HK receiver.

There area a number of 3-channel used amps that may do the job (Adcom, Rotel, Carver). You can often find them in the Flea Market here or various web sites like Fleabay etc. The Flea Market here is a good place to start. Ask for specific 3-channel advice from the members here. You should probably make the speaker selection before you choose the amp as appropriate power is an important consideration. As for new 3-channel amps, very few companies make them anymore as most home theaters are either 5 or 7 channel. One company that does is Emotiva however the XPA-3 is $600 which would exceed your budget. You may have to go the used route if you stay with your budget. There may also be an issue finding a used 3-channel with enough power IF you stay with the LSI's and your budget remains at $400.

Regardless of the amp you choose or locate, the hookup would be as follows. The surround speakers would remain connected to the HK as they are now. No change required. The speaker wires to the left, right, and center speakers would be disconnected from the HK and connected to the back of whatever amplifier you get. The connectors are similar to the HK speakers connectors you currently use. Whatever amplifier you get would be connected to the HK by RCA-type cables from the appropriately labels Pre-Outs on the HK to the Left-Right-Center input RCA connectors on the new amplifier.

If you find a 5-channel amplifier (new or used), the connections would be the same except you would include the surround speakers also. In other words, all speakers would be connected to the amplifier, and the amplifier would be connected to the HK with 5 RCA cables. In that case, your HK would in effect become a processor only and its amplifiers would not be used.

Make sense?

bdtae5656 · March 2009

Yes makes perfect sense! Im looking at the LSI15's or Rti9's and 7's. So I dont want to rewire the Low's back to the HK? Or is that optional....thats bi-amping right? Yes Im going to keep my HK. What speakers from Polk do you suggest and what Amp and what size so I be looking for?
Thanks a million
-How will the Lsi's and or Rti;'s sound without the amp, thats until I can find teh right one and bugdet it

Marty913 · March 2009

bdtae5656 wrote: »

Yes makes perfect sense! Im looking at the LSI15's or Rti9's and 7's. So I dont want to rewire the Low's back to the HK? Or is that optional....thats bi-amping right? Yes Im going to keep my HK. What speakers from Polk do you suggest and what Amp and what size so I be looking for?
Thanks a million
-How will the Lsi's and or Rti;'s sound without the amp, thats until I can find teh right one and bugdet it

I'm not sure what you mean by "rewire the Low's". Please explain. I would assume you're not bi-amping the Bose L/R so I guess I'm lost as to exactly what you have. Please describe ALL your speakers and current hookup.

As suggested by tonyb in post #2, if you are looking at the RTi line and not the LSI line then you may get by with your HK-AVR354 for a while. The issue (I think) has been going with all LSI versus finding a better match for your HK OR getting more amplifier power. IF you are thinking RTi7 why not get a CSi A4 or A6 Center and stay with the HK 354 for a while and skip the 3-channel amp hunt for the time being. The HK 354 you have is a relatively high current solid amp and would probably be fine with RTi's.

Maybe someone with RTi's can jump in here and tell us if they are driving them adequately with a receiver. If I were you, I would do the following:

Pick your speakers (all of them)
Based on that, look at the amp situation (IF required)
Worry about bi-amp / bi-wire WAY down the road

bdtae5656 · March 2009

No im not bi-wiring or amping at this time....my question was should I Bi-amp the Lsi C and or LSI-15's and or Rti's?

bdtae5656 · March 2009

Marty913 wrote: »

I'm not sure what you mean by "rewire the Low's". Please explain. I would assume you're not bi-amping the Bose L/R so I guess I'm lost as to exactly what you have. Please describe ALL your speakers and current hookup.

As suggested by tonyb in post #2, if you are looking at the RTi line and not the LSI line then you may get by with your HK-AVR354 for a while. The issue (I think) has been going with all LSI versus finding a better match for your HK OR getting more amplifier power. IF you are thinking RTi7 why not get a CSi A4 or A6 Center and stay with the HK 354 for a while and skip the 3-channel amp hunt for the time being. The HK 354 you have is a relatively high current solid amp and would probably be fine with RTi's.

Maybe someone with RTi's can jump in here and tell us if they are driving them adequately with a receiver. If I were you, I would do the following:

Pick your speakers (all of them)
Based on that, look at the amp situation (IF required)
Worry about bi-amp / bi-wire WAY down the road

What do you think about AVANTI A.100??? http://www.audiopro.com/templates/audio_pro_products/?id_products=425

Marty913 · March 2009

bdtae5656 wrote: »

What do you think about AVANTI A.100??? http://www.audiopro.com/templates/audio_pro_products/?id_products=425

Don't really know anything about them but based on their 4 ohm rating I would say they would not be a good match for your current receiver. One could assume that 4 ohm speakers (especially mains) will drop below 4 occasionally into perhaps the 2 ohm range. Your HK has a good deal of current (35 Amp) for instantaneous power but driving mains full time would not be advisable. That of course puts you back into the external amp issue. It would also be a "crap shoot" as to whether it matches up with you LSI center.

bdtae5656 · March 2009

Marty913 wrote: »

Don't really know anything about them but based on their 4 ohm rating I would say they would not be a good match for your current receiver. One could assume that 4 ohm speakers (especially mains) will drop below 4 occasionally into perhaps the 2 ohm range. Your HK has a good deal of current (35 Amp) for instantaneous power but driving mains full time would not be advisable. That of course puts you back into the external amp issue. It would also be a "crap shoot" as to whether it matches up with you LSI center.

What do you think would be a good solid speaker for my money???? Amp or no amp. Im going to buy a 3 channel amp in the long run, but I want to focus on picking the correct L/R before anything else!
Thanks for your advise and help

Marty913 · March 2009

bdtae5656 wrote: »

What do you think would be a good solid speaker for my money???? Amp or no amp. Im going to buy a 3 channel amp in the long run, but I want to focus on picking the correct L/R before anything else!
Thanks for your advise and help

Well, I'm a huge Polk fan or I wouldn't be here so I would be uncomfortable recommending a non-Polk speaker here on the Forum. I also like the older SDA models from the 80's. That being said, I understand that you seem to be building a newer system, and that you like floor-standing speakers. Polk of course makes it easier for you to match the LSI center if you keep it. You also mentioned value and I believe Polk is where the value is at.

For a really budget pair but still much better than your Bose, the R300's offer a huge value for almost dirt-cheap money.

For a step up, (you didn't mention a budget), I would say the TSi series (models 400-500) would be good ones to look at.

Next up, I really like the RTi A5 and A7's. Of course the A9's are great.

All of these are 8 ohm and 90db efficient so your HK should drive any of them very well. Adding more power later (especially for the RTi's) would be great but you would not need it to start.

bdtae5656 · March 2009

Marty913 wrote: »

Well, I'm a huge Polk fan or I wouldn't be here so I would be uncomfortable recommending a non-Polk speaker here on the Forum. I also like the older SDA models from the 80's. That being said, I understand that you seem to be building a newer system, and that you like floor-standing speakers. Polk of course makes it easier for you to match the LSI center if you keep it. You also mentioned value and I believe Polk is where the value is at.

For a really budget pair but still much better than your Bose, the R300's offer a huge value for almost dirt-cheap money.

For a step up, (you didn't mention a budget), I would say the TSi series (models 400-500) would be good ones to look at.

Next up, I really like the RTi A5 and A7's. Of course the A9's are great.

All of these are 8 ohm and 90db efficient so your HK should drive any of them very well. Adding more power later (especially for the RTi's) would be great but you would not need it to start.

Im deeply thinking about the Rti A9's....when I get a amp down the road will it affect that I have a Center thats 4ohm and the floors are 8ohms? What is a good solid 3 channel amp to power the center and floor speakers? What watts, etc.
Thanks,

Marty913 · March 2009

bdtae5656 wrote: »

Im deeply thinking about the Rti A9's....when I get a amp down the road will it affect that I have a Center thats 4ohm and the floors are 8ohms? What is a good solid 3 channel amp to power the center and floor speakers? What watts, etc.
Thanks,

No, it will have no effect on the center. A quality amp will handle mixed 4, 6, and 8 ohm speakers easily. You may not want to limit yourself to a 3-channel amp, especially if you are shopping used. Some of the best deals are on 5-channel amps and there are a lot more of them around than 3-channel amps. What you really want is "at least" 3-channels.

Assuming used, look for models from Adcom, Rotel, and Carver. Some models are the Carver A-753x or AV-705x, the Rotel RMB-1075 or 985, and the ADcom GFA-6000 or 7000 or 5503. There are other brands including NAD, Outlaw, B&K, and Parasound, and Sunfire. Keep an eye out here or on Fleabay.

New is a whole other deal, especially budget-wise. I mentioned Emotiva before and that is probably the least expensive.

bdtae5656 · March 2009

Marty913 wrote: »

No, it will have no effect on the center. A quality amp will handle mixed 4, 6, and 8 ohm speakers easily. You may not want to limit yourself to a 3-channel amp, especially if you are shopping used. Some of the best deals are on 5-channel amps and there are a lot more of them around than 3-channel amps. What you really want is "at least" 3-channels.

Assuming used, look for models from Adcom, Rotel, and Carver. Some models are the Carver A-753x or AV-705x, the Rotel RMB-1075 or 985, and the ADcom GFA-6000 or 7000 or 5503. There are other brands including NAD, Outlaw, B&K, and Parasound, and Sunfire. Keep an eye out here or on Fleabay.

New is a whole other deal, especially budget-wise. I mentioned Emotiva before and that is probably the least expensive.

What do you think about RTi 9's with B&K AV5000, and or Adcom GFA-5503 3-C???

Marty913 · March 2009

bdtae5656 wrote: »

What do you think about RTi 9's with B&K AV5000, and or Adcom GFA-5503 3-C???

I don't think the B&K is a huge jump over what you have - perhaps not for what you will pay for it. I always thought the older B&K's were a little on the "too warm" side for me but I am not familiar with the 5000.

Adcom has a huge following on the forum which is probably a good sign. I owned a couple back in the early 90's and was very happy with them. If I were you and were seriously thinking of getting RTi 7's or 9's that you should start a new post and specifically ask the members how the 5503 would be at driving the (whatever specific speaker model you decide on). Only someone with the 5503 and RTi's would probably know for sure. Having said that, the Adcom is plenty powerful and popular so at the right price I'm sure it would work out fine for you. There were more made than B&K so they will probably be easier to find, less expensive to buy, and easy to get repaired should you need that.

seafire · March 2009

BlueFox wrote: »

Underpowering a speaker damages it? Sorry, but that is just wrong. Clipping a speaker can damage it, but pumping 1W into a speaker will not hurt it.

I hope what you meant to say was using a low power, low end amp, AVR, receiver, etc., and playing it at max volume has the potential to damage a speaker. Any speaker.

I personally ran 4 LSi15s, and an LSiC with a Denon 3805 and a Sony 5000ES for two years with no problem. After upgrading to a Sunfire TGA5400 the speakers still work, and sound better.

Tell me are you using the 3805 as pre amp??I run a Sunfire signature with a 3805 as pre amp...pretty good but maybe I wasted my money Try running the 3805 in bi amping mode and you will realize we didnt need the Sunfire's extra 1%.If you are interested I can show you how to do this Seafire

rubin · March 2009

I hd an HK 690 receiver driving paradigm 100"s at fairly high levels without problems. It was rated at 60 wpc with 45 amps.I did read that the 100"s would dip to 3 ohms.

Michael_Js · April 2009

hmm...that's an issue

Bi-Amp

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