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Topic: Polk LSi9 Amp Pairing (Read 11723 times) previous topic - next topic
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Polk LSi9 Amp Pairing

I am very interested in buying a pair of Polk LSi9's but I am uncertain about their power requirements.
right now I'm between Emotiva XDA-1 plus UPA-2 185w@4ohm or XDA-1 plus two Outlaw 2200 300w@4ohm.
what I like about the XDA-1 is that it can act as the system sound card
the setup will be pc to amp in whatever configuration I go with.

considering it is a small room and will be played at moderate levels most of the time would the UPA--2 be 'enough'
i have read a lot of posts that say the Outlaw 2200's are 'enough'
cost is a consideration and these units are the minimum but just about right in my price range.
I also see the Pyle 3000w amplifiers, dirt cheep but then you read the reviews and they say it's more like 70w per channel.

I also like the idea of getting a receiver with pre-outs so I can do multi channel for movies or the Polks' as mains for music.
I know there are a lot of options available but the Polks' have a rep as being power hungry and my main concern right now is making sure i have adequate power for them and then I can go from there.

any alternatives or suggestions are appreciated, thanks.

Polk LSi9 Amp Pairing

Reply #1 –
I'd say this is a question that can't really be answered 'till you find yourself driving your amp into clipping...  If you are designing a pro set-up you can make reasonable predictions based on the desired SPL, size of venue, speaker efficiency, etc.  But for the home there are too many variables, including the desired SPL and the effect of reflections.

One approach is, "You can never have too much power available."

As you probably know, a doubling of power is only 3dB, which you would rarely notice, since you (hopefully) are not typically driving your amp to clipping anyway.

I don't know about the Polks, but my rule-of-thumb is "100W is plenty" for a living room. (Maybe more for the subwoofer.)    And, I just use that as a reference point, because you don't find many receivers with less than 100WPC.  My "bottom-of-the-line" Sherwood receiver is rated at 100W x5.    (I don't know if that spec is real...)  If you had a power meter, you might find that you're typically running less than 20W.    It's too bad that peak-power meters on amps are so rare, but you can find amps with clipping indicators.  (If they put power meters on amps, a lot of people would probably blow-up their speakers trying to see the meters go-up!  )

Quote
I also see the Pyle 3000w amplifiers, dirt cheep but then you read the reviews and they say it's more like 70w per channel.
Yeah, the manufacturer's seem to have strayed from standardized (IEC?) measurements...  What you want to look for is something like, "X watts per channel continuous RMS, both channels driven, 20-20kHz @ less than X% distortion."    If the manufacturer doesn't publish "real specs", I wouldn't trust 'em.

Speaker power ratings are just as dubious.  I think most (good) home-speaker manufacturers give you "recommended amplifier power", rather than the amount of continuous power that the speaker can take.    But, it's not something I'd worry about because speakers rarely get blown-out except during "loud parties".

Even the proper/professional speaker ratings are done with "shaped" noise (pink noise or similar) because the tweeter can't handle the kind of power that a woofer can...  You can probably blow-out most home tweeters with 20W test tones.    IIRC, JBL recommends an amp rated at twice the speaker rating for high-quality (low distortion music) pro applications.

Polk LSi9 Amp Pairing

Reply #2 –
Quote from: foodunit on
I am very interested in buying a pair of Polk LSi9's but I am uncertain about their power requirements.
right now I'm between Emotiva XDA-1 plus UPA-2 185w@4ohm or XDA-1 plus two Outlaw 2200 300w@4ohm.
what I like about the XDA-1 is that it can act as the system sound card
the setup will be pc to amp in whatever configuration I go with.


I don't see a lot of difference between these amps. Ther is about 2.5 dB power difference betweent them, but it takes a power difference of about 10 dB (10X) to create the impression of "twice as loud".

If you want something a little louder for about the same money, thy this:

A somewhat more powerful amp for the money

Polk LSi9 Amp Pairing

Reply #3 –
Quote from: DVDdoug on
I'd say this is a question that can't really be answered 'till you find yourself driving your amp into clipping...  If you are designing a pro set-up you can make reasonable predictions based on the desired SPL, size of venue, speaker efficiency, etc.  But for the home there are too many variables, including the desired SPL and the effect of reflections.

One approach is, "You can never have too much power available."


But you can. It is now too easy to economically come up with enough power to hurt most speakers.

Quote
As you probably know, a doubling of power is only 3dB, which you would rarely notice, since you (hopefully) are not typically driving your amp to clipping anyway.

I don't know about the Polks, but my rule-of-thumb is "100W is plenty" for a living room. (Maybe more for the subwoofer.)    And, I just use that as a reference point, because you don't find many receivers with less than 100WPC.  My "bottom-of-the-line" Sherwood receiver is rated at 100W x5.    (I don't know if that spec is real...)  If you had a power meter, you might find that you're typically running less than 20W.    It's too bad that peak-power meters on amps are so rare, but you can find amps with clipping indicators.  (If they put power meters on amps, a lot of people would probably blow-up their speakers trying to see the meters go-up!  )


I agree that 100 wpc is a good starting point, and its also a fine finishing point for many people. I use a 2-channel ca. 100 wpc Sherwood to drive my AV room system.

The OP's speakers of choice are 88 dBW sesitibity, so 100 watts is good for 108 dB at a meter, easily a clean 100+ dB peaks in an average room with two speakers.

Slightly tongue in cheek I posted the OP a link to Behringer's more recent high powered amp which will really punch out  maybe 1200-1500 wpc into 2 ohms, maybe 750 at 4 ohms, and at least 350 watts into 8 ohms. Two of them bridged would fit into his budget and give about a 1 KW or more into 8 ohms.  I'd recommend fusing the speakers with 4 amp fuses! ;-)

I'd bet money that a pair of bridged EP-4000s would either pop the 15 amp circuit room ibreaker, or seriously damage a pair of Polk LSi9's if pushed to their maximum.

Polk LSi9 Amp Pairing

Reply #4 –
i know this is a confusing and yet simple issue with too many variables to be able to just nail it.
if you go by 100w is enough then shouldn't any given receiver rated at 100w be 'enough'. yet, everything I've read says it's not enough and that you would want to run it through a power amp with these speakers. again most say the Outlaws are about perfect at 300w@4ohm. therefore I would assume the Emotiva at 185w@4ohm would not be enough. but of course I would have to buy 2 outlaws. although my impression is that the Emotiva would be enough. I just do not have enough experience with higher end stuff to take an educated stab at it.

sort of, what does it take to get these speaker to preform in their full glory at any volume. that is one thing that confuses me. it is not 300w utilised by the speaker at any given level, it is not a continuous 300w. it's 'up to' 300w or 185w. so if I turn the speaker volume up half way its using at least 150w, right? given the equation of how many watts it take for an increase in dB this can't be true. on the same token the Polks' recommended amplifier power 20 - 200 w/channel. so the Emotiva from 0-185 w should be enough. most would say it's not and that i would want the Outlaws. 100w from the Emotiva is the same as 100w from the Outlaw, right?

now I'm confeused again, goodnight........................

Polk LSi9 Amp Pairing

Reply #5 –
Quote from: foodunit on
i know this is a confusing and yet simple issue with too many variables to be able to just nail it.


Right we really need a lot of data if we were going to do a thorough analytical job. One of hte most important questions would be "At what dB SPL level do you want to listen" which you are probably unprepared to answer exactly.

Quote
if you go by 100w is enough then shouldn't any given receiver rated at 100w be 'enough'. yet, everything I've read says it's not enough and that you would want to run it through a power amp with these speakers. again most say the Outlaws are about perfect at 300w@4ohm.


Most 100 wpc receivers are specd at 8 ohms which mean that they will deliver music at 140-150 watts, 300 watts is only 3 dB more than 150 watts and as always, it takes 10 dB more power to obtain the impression of twice the loudness.

Quote
therefore I would assume the Emotiva at 185w@4ohm would not be enough. but of course I would have to buy 2 outlaws. although my impression is that the Emotiva would be enough. I just do not have enough experience with higher end stuff to take an educated stab at it.



You are missing the point - if you want something apreciably louder than what a humber 100 wpc receiver will do, you need a lot more than a 300 watt amp.

Quote
sort of, what does it take to get these speaker to preform in their full glory at any volume. that is one thing that confuses me. it is not 300w utilised by the speaker at any given level, it is not a continuous 300w. it's 'up to' 300w or 185w. so if I turn the speaker volume up half way its using at least 150w, right?


No.  Even if your playback was peaking at 300 watts, much of the time the actual power from your amp into each of  your speakers would be in the 30-50 watt range or less.

Most people don't listen that loud most of the time. Most of the time the power is in the 5-50 watt range, or less.

Polk LSi9 Amp Pairing

Reply #6 –
Like I said... No solid answers, just guidelines, rules-of-thumb, and different approaches/philosophies...


Quote
.. so if I turn the speaker volume up half way its using at least 150w, right?
Half-way to what?  Half-way to "burn-out"?  Half-way to "distortion"?

Quote
...it is not 300w utilised by the speaker at any given level, it is not a continuous 300w. it's 'up to' 300w or 185w.
The nature of music is such that the peaks are typically 5-10 times the average level (depending on the music of course).  So, it's the high-end of the high-end of amplifier power that limits the peaks.  But, it's continuous (average) power that overheats & burns-out a speaker.    If speaker manufacturers were to publish continuous power ratings, speakers would be rated for very low power, and the ratings would be useless for music.  And, if they were to publish "safe operating area" data for short-duration peaks, that would be useless too because every song is different.   


Quote
given the equation of how many watts it take for an increase in dB this can't be true.

dB = 10 x log (power ratio*)  i.e. 10log (200W/100W) = 3dB.
Or, power ratio = 10^(dB/10)
That's true as long as the speaker is operating linearly.  At some point, you increase power and the driver does not move proportionately. 

Quote
...on the same token the Polks' recommended amplifier power 20 - 200 w/channel.
Just semi-helpful guidelines...  i.e. "You might want more than 10W, but you probably don't need 500W."

I remember one manufacturer that listed a higher minimum power rating for a higher-end speaker that was more efficient (louder at a given power) than the less-expensive speaker.  It doesn't always make much sense...  I guess they are thinking that you need more power to utilize the full-power/loudness of the more expensive speaker.  And, most higher-end buyers are going spend more on the amp too. 




* That formula is for power (Watts).  For voltage (or the digital level in an audio file) the formula is 20x log (ratio).  This is because when you increase the voltage (or "level") you proportionately increase the current.  i.e. If you double the voltage, the current doubles, and the the result is 4 times the power (+6dB).

Polk LSi9 Amp Pairing

Reply #7 –
let me re-objectify my issue, the Polk LSi9's will be played in a 9' by 11' room at moderate levels. just loud enough not to be able to talk over, if that, say 60-70dB. how loud any given amp can make these speakers is not my primary concern. I will most likely buy one of the two named amps; Emotiva or Outlaw. between the two, my main concern is would the Emotiva under power the Polks'. the way I see it stated in other posts is that, if these speakers are 'under powered they' will not 'preform' as they should. preforms as in translating the sound, not level of volume. the only distinction made is that you want an amp with adequate power so that they can 'preform' correctly.

everything DVDdoug and Arnold B. Krueger supports the idea that the Emotiva would not necessarily under power the LSi9's and that the Outlaws would perhaps merely push it a lil further. I appreciate the replies, thank you. I just think I should narrow it down and confirm the question is basically between the two amps.

I am also somewhat convinced that my onkyo 607 might do the trick and I don't need A power amp.
just to throw it out there what does anybody think of the Onkyo A-5VL Integrated Amplifier for the Polks'

thanks again and all reads and replies are appreciated.

Polk LSi9 Amp Pairing

Reply #8 –
Quote from: foodunit on
let me re-objectify my issue, the Polk LSi9's will be played in a 9' by 11' room at moderate levels. just loud enough not to be able to talk over, if that, say 60-70dB. how loud any given amp can make these speakers is not my primary concern. I will most likely buy one of the two named amps; Emotiva or Outlaw. between the two, my main concern is would the Emotiva under power the Polks'. the way I see it stated in other posts is that, if these speakers are 'under powered they' will not 'preform' as they should. preforms as in translating the sound, not level of volume. the only distinction made is that you want an amp with adequate power so that they can 'preform' correctly.

everything DVDdoug and Arnold B. Krueger supports the idea that the Emotiva would not necessarily under power the LSi9's and that the Outlaws would perhaps merely push it a lil further. I appreciate the replies, thank you. I just think I should narrow it down and confirm the question is basically between the two amps.

I am also somewhat convinced that my onkyo 607 might do the trick and I don't need A power amp.
just to throw it out there what does anybody think of the Onkyo A-5VL Integrated Amplifier for the Polks'

thanks again and all reads and replies are appreciated.


The Onkyo 607 will be fine.

There's no way you're getting anywhere near 300W if you're only looking for 60-70dB average volume. Let's take the high end and add 20dB for transients (sadly optimistic due to the sad state of mastering these days), giving you 90dB. You will need <10W on 88dB speakers to hit those transient peaks! I'm in a similar room, with similar efficiency speakers and a 130W/channel amp. I never get near the top end of it.

Polk LSi9 Amp Pairing

Reply #9 –
Quote
how loud any given amp can make these speakers is not my primary concern. I will most likely buy one of the two named amps; Emotiva or Outlaw. between the two, my main concern is would the Emotiva under power the Polks'. the way I see it stated in other posts is that, if these speakers are 'under powered they' will not 'preform' as they should.
What???  A speaker converts electrial energy into acoustic energy.  More power (watts) into the speaker means more acoustical energy/loudness (SPL).  Unused available-power (headroom) doesn't change the sound.

...Let's say you have two amps.  A 10W amp and a 1000W amp.  And, let's assume that other than power capability, the specs are identical (same gain, noise, distortion, and frequency response at any level below 10W).

And, let's assume you are playing music and the peak power from hits 9W.  You can switch between amps and both amps will sound identical.  There is no "performance difference", since in both cases the same electrical signal is going into the speakers.  The extra 991 Watts of headroom has no effect whatsoever on the sound.

Now, you are listening to the 1000W amp, and you turn-up the volume to where the peaks are hitting 15W.  If you switch to the lower-power amp (at the same attemped volume) you'll get clipping/distortion.  Now, there's a performance difference.

Polk LSi9 Amp Pairing

Reply #10 –
Carrying on the 10W vs. 1000W analogy, it is also noteworthy that the 1000W amplifier, when operating at the same output power as the 10W amplifier, is operating 20 dB closer to its noise floor.

In other words, the 1000W amplifier has 10x higher gain than the 10W amplifier, so the signal input to the 1000W amplifier needs to be 10x smaller to produce the same output power.

The bottom line is that the 1000W amplifier could actually be noisier than the 10W amplifier.

Polk LSi9 Amp Pairing

Reply #11 –
Quote from: lessthanjoey on
The Onkyo 607 will be fine.

There's no way you're getting anywhere near 300W if you're only looking for 60-70dB average volume. Let's take the high end and add 20dB for transients (sadly optimistic due to the sad state of mastering these days), giving you 90dB. You will need <10W on 88dB speakers to hit those transient peaks! I'm in a similar room, with similar efficiency speakers and a 130W/channel amp. I never get near the top end of it.


perhaps it's the speakers I have the wrong impression of. they have a reputation of being power hungry, but if the Onk would actually drive them, I don't see why the point is made for power amps. I am making the upgrade to LSi9's from Energy cf-50's in hope of improvement, but maybe it's not going to be as much of one as I thought. the Energy speakers are really nice from it's own level and I do like them. but i still need a lil more depth to the sound. the ring radiator tweeters are appealing  and the LSi9 rep makes me think they would be more robust.

it's ironic but the last upgrade I made was the Onkyo TX-SR607 and a pair of Polk TSi200's. I should have bought a Stereo receiver rather than an A/V receiver since it was just for stereo music. the TSi's were not going to cut it and Amazon had the cf-50's on sale for 1/2 price so I snagged 'em. so far, I'm fairly pleased with them. they have subtle audiophile qualities and are fairly ballsy. they are good for all genres are continue to impress me with what they can do. but something is still missing. (and no, it's not the sub woofer  ) although the cf-50's and the LSi9's retail for about the same i still feel as if it's a significant upgrade, especially with the rep the LSi9's have vs. Energy being looked at as a Klipsh overly bright baby. I would prolly upgrade to higher end Energies' but RC-70's have been discontinued and the next level starts at about twice what the Polks' retail for, which is juat a lil out of my price range. but having no luck with the Polks the first time around  I don't want to buy a glorified TSi200

I am also interested in the subject of possible configurations for pc to output. stereo receivers vs A/V receivers. integrated amps vs pre-amp/power amp. (what I like about the Onkyo integrated amp is that it has digital input for s/pdif out from a sound card, burr brown DAC but then its 40w). some say direct digital out card to an external DAC to powered speakers. all the different options for sound cards, external/internal, combos. last i read direct digital is integrated in most common cards (i have bgears b-enspirer with s/pdif out). which is why I like the idea of the Emotiva pre-amp best possible connection between pc and amp according to design. according to the manual if you connect it from pc with usb the pc will utilise it as the system sound card, (i mean that's one hell of a sound card). to the power amp to the Polks'


Quote from: DVDdoug on
Quote
how loud any given amp can make these speakers is not my primary concern. I will most likely buy one of the two named amps; Emotiva or Outlaw. between the two, my main concern is would the Emotiva under power the Polks'. the way I see it stated in other posts is that, if these speakers are 'under powered they' will not 'preform' as they should.
What???  A speaker converts electrial energy into acoustic energy.  More power (watts) into the speaker means more acoustical energy/loudness (SPL).  Unused available-power (headroom) doesn't change the sound.

...Let's say you have two amps.  A 10W amp and a 1000W amp.  And, let's assume that other than power capability, the specs are identical (same gain, noise, distortion, and frequency response at any level below 10W).

And, let's assume you are playing music and the peak power from hits 9W.  You can switch between amps and both amps will sound identical.  There is no "performance difference", since in both cases the same electrical signal is going into the speakers.  The extra 991 Watts of headroom has no effect whatsoever on the sound.

Now, you are listening to the 1000W amp, and you turn-up the volume to where the peaks are hitting 15W.  If you switch to the lower-power amp (at the same attempted volume) you'll get clipping/distortion.  Now, there's a performance difference.


right, exactly, the effect is direct not collective. speakers will not utilise more power then what you manually feed it, the rest is headroom. the drive is the same per watt. performance is more speaker quality and not power utilisation. so if I don't need more then 185w the rest is unused and will drive the speakers as far as they can go with the same 185w with a 300w amp. if the Polks' are not expected to use more than 20-50watts maybe my Onk would suffice after all. in some other forum someone told me they doubt my cf-50's are using more than 1watt. the Onk is rated@90w so it should push more power to the right speaker. which gets into the issue of "all channels driven" is it 90w per channel or 90w between the 7??


Quote from: pdq on
Carrying on the 10W vs. 1000W analogy, it is also noteworthy that the 1000W amplifier, when operating at the same output power as the 10W amplifier, is operating 20 dB closer to its noise floor.

In other words, the 1000W amplifier has 10x higher gain than the 10W amplifier, so the signal input to the 1000W amplifier needs to be 10x smaller to produce the same output power.

The bottom line is that the 1000W amplifier could actually be noisier than the 10W amplifier.


I think that's a great point to make. which is also one of my concerns. more than enough power might be overkill rather than comfortable headroom.

thanks all

Polk LSi9 Amp Pairing

Reply #12 –
please, any further comments or suggestions are welcomed.

thanks

Polk LSi9 Amp Pairing

Reply #13 –
I had missed that your current speakers (Energy CF-50) were 96dB sensitive! The Polk LSi9 requires 7x the power for the same volume level. That's a relatively large difference.

Having said that, 90W should still be enough for all the reasons stated above. Most importantly, it'll allow 107dB maximum output.

(As an aside, "all channels driven" is a good thing - essentially it means that all 7 channels can simultaneously put out 90W. Some really cheap receivers don't have a strong enough power supply for all channels to support that power at once)



Could you articulate further on what you think is missing at the moment? Personally, I would also look at your listening room. You can look at treating the first reflection points, as well as try to lower overall reverberation time (RT60) with room treatment. For me, that provided the strongest subjective improvement.

Polk LSi9 Amp Pairing

Reply #14 –
what is missing is what I hope to get from the upgrade to LSi9's. just a lack of overall sound depth. it doesn't flood the room and it doesn't pour out of the speakers. it's more projected and itemized. even though it's how loud speakers work. there is just no "solid core of sound". I don't know how to describe it, and maybe it's just me. it just seems back in the old days when you were in a room with a killer setup the sound just seemed so big (or deep). maybe it's the Onk

I am currently considering the HK 150 watts times 2 at 4 ohms. It has 45 amps of current. digital inputs. pre-outs. cheap price.

the Yamaha HTR-6230 is dirt cheap and clains 100W x 5 or a total of 500w but I don't know if it does 4ohm.

thanks

Polk LSi9 Amp Pairing

Reply #15 –
Quote from: foodunit on
what is missing is what I hope to get from the upgrade to LSi9's. just a lack of overall sound depth. it doesn't flood the room and it doesn't pour out of the speakers. it's more projected and itemized. even though it's how loud speakers work. there is just no "solid core of sound". I don't know how to describe it, and maybe it's just me. it just seems back in the old days when you were in a room with a killer setup the sound just seemed so big (or deep). maybe it's the Onk

I am currently considering the HK 150 watts times 2 at 4 ohms. It has 45 amps of current. digital inputs. pre-outs. cheap price.

the Yamaha HTR-6230 is dirt cheap and clains 100W x 5 or a total of 500w but I don't know if it does 4ohm.

thanks


I highly doubt it has anything to do with the Onkyo. If amplifiers aren't clipping and don't have atrocious levels of distortion or frequency response deviation (and the Onkyo passes both of these without trouble) then blind tests have never shown any ability to discriminate between them.

Further, your current speakers are extremely efficient so there's no way that the Onkyo is even close to clipping.

I know you said that you don't think it has anything to do with the lack of a subwoofer, but bass response definitely provides a "fullness" in sound.

And secondly, I'm going to double-down on my prior suggestion that it's primarily your room that is lacking, more so than the speakers, and infinitely more so than the amplifier. The only way around this is room treatment. Can you describe your room (size, surfaces) to us?

Polk LSi9 Amp Pairing

Reply #16 –
room correction is something I am unwilling/ or am unable to do.
my concern is focused on quality of speaker and correct amp pairing.

thanks

Polk LSi9 Amp Pairing

Reply #17 –
Quote from: foodunit on
room correction is something I am unwilling/ or am unable to do.
my concern is focused on quality of speaker and correct amp pairing.

thanks


"Correct amp pairing" is already taken care of unless you go out and buy extremely inefficient speakers. I think we've beaten that horse to death.

If you're unwilling to look into room treatment consider trying to find a speaker with a fairly uniform, but not too wide radiation pattern to limit room interactions. That, in addition to a subwoofer are really the only other possibilities for solving what you're alluding to (however, be careful of the subwoofer as you have some easily excitable and not too deep room modes - resonance frequencies - in a room that size).

Polk LSi9 Amp Pairing

Reply #18 –
another issue I need help with is when running a A/V receiver through the pre outs to a power amp does the receivers settings still apply? such as speaker level/distance listening mode ect. or is the signal clean and unaffected by the receiver?

thanks

Polk LSi9 Amp Pairing

Reply #19 –
Quote from: foodunit on
another issue I need help with is when running a A/V receiver through the pre outs to a power amp does the receivers settings still apply? such as speaker level/distance listening mode ect. or is the signal clean and unaffected by the receiver?


Usually, only things like speaker selector switches are bypassed by using the preamp outputs of a receiver.

The items you mention are probably all handled by the receiver's main DSP, which is in the signal path no matter which way you go.

The preamp outputs will reflect DSP in/out settings for receivers that have a means for completely bypassing the DSP.

Polk LSi9 Amp Pairing

Reply #20 –
any opinions on DefTEch BP10B?

P.S. the HK 3490 is what i refered to.

thanks

Polk LSi9 Amp Pairing

Reply #21 –
I think you're good. You don't need an amp, you'll just need a bit more of a rotation of the volume knob to get the Polks to the same level of the Energys, but it will be worth it in my opinion. I'm not a fan of the Energys. The Def Techs? Big, room-filling sound from the bi-polar design. Less of a load on your Onkyo, than the Polks because of the powered subwoofers. They can be very boomy, though - turn those subs down and don't place them too close to the walls/corner. And they can be too bright, or just right, depending on your taste and your room, due to the metal tweeters and bi-polar design. This is where the sound is made -- speakers. Stop worrying about amps. Find the speakers you love. Unless they are very inefficient, the Onkyo will drive them just fine.

Tim

PS: most modern receivers have some kind of direct mode which bi-passes all the processors, tone controls, sometimes even turns off panel lights, and goes straight from volume control to the amps. I don't know if a direct mode would also go straight to preamp outs. You would need to research that one.