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Need suggestion on tube amplifier with XLR inputs

I am looking for a two channel tube amplifier (not sure of the wattage I will need as I am not 100% sure how the wattage correlates to transistor wattage so I will need a recommendation on this as well). My current set up is as follows: Emotiva DMC-1 Pre-amp/processor, Behringer cross-over, Emotiva XPA-5 (5 channel amplifier) and a Krell KSA-250 (2 channel amplifier) I have them connected via XLR cables throughout. I use the Krell to power my two JL-Audio 13W7 subs. I use the XPA-5 to run all other speakers at this time. What I would like to do is purchase a 2 channel Tube amplifier to run my center channel speakers as these are responsible for most of the mids/highs and use the 5 channel XPA-5 to run the surround speakers. My thought is that the center is responsible for most of the sound in a 5.2 system anyway so if I were to put my money on adding quality sound this would be the spot to do it. I need a two channel as I would like to run my tweeter on a separate channel then the mids so as to isolate each signal through the cross-over to have more granularities in tuning each of them. My tweeter has a speaker efficiency of 106 db and my mids are 87 db. If I run them through the same channel the tweeter will obviously overwhelm the mids and does as I have tried this already. So my question is, what 2 channel tube amp would you recommend that would drive 3 4” midrange drivers on one channel and then on the other drive 2 tweeters? I think I need something that would equal around 200 transistor type watts per channel as that is what the other surround speakers have running to them. I thank you in advance for any and all advice!

P.S. I would like to keep the cost under $3000 and am perfectly fine with purchasing used equipment. Thanks again!
ectomorph81
ectomorph81 OP
12 posts
 
Forgot to mention that this setup will in the end be a 5.2 system used for HT (the room is not large enough for a 7.2 system) As for right now it is mainly used for music. I would like all the front speakers in this system to be driven by tubes and the less used rear speakers I will just use a quality SS as these are not the main focus anyhow. Also I will be running the speakers in series so as to lessen the load on the tube amp. Depending on which amp I go with I will present a 8ohm load or higher to the amp. My end goal here is to have my front center speaker consist of 4 Morel 531's and 2 tweeters. Each of the left and right side monitor's will have 3 Morel 531s and 2 tweeters apiece.
ectomorph81 OP
12 posts
 
As of right now I have the cutoff set to 80hz but I can change it in the crossover at anytime. I also can change the slopes if necessary as well. The cross-over I have is pretty much infinitely adjustable. Thanks again for your help guys!

Mello
atmasphere's avatar
atmasphere
11,837 posts
 
Mello, there are not a lot of low power balanced amps out there. Our S-30 is likely one of the few, but it is a stereo amplifier, so you would have to accommodate that if that is how you proceeded. It might be easier to get some smaller amp since the tweeter only needs a couple of watts, and run the amp using half of the balanced signal, while loading the other half so that the balanced operation is maintained.

The midrange is going to need more power- 60 watts might actually be enough, depending on the room. As a side note, I would also try operating the tweeter off of the midrange amp, using an attenuator to reduce its level. You may find it sounds better- electronic crossovers often rob the system of detail.
ectomorph81 OP
12 posts
 
So, are you suggesting that I use a passive cross-over for my highs which in turn would allow me to use an RCA connection as I would not have to run it through my electronic cross-over? If so what amp would you suggest in that case? I had always been under the impression that electronic cross-overs were the way to go for sound quality? Or do you suggest using a passive cross-over on my mids as well? If so what amp would you use?

by attenuator do you mean an L-pad?

thanks a ton Atmashere! I really appreciate all your help!

Sincerely,
Mello
atmasphere's avatar
atmasphere
11,837 posts
 
Attenuator- L-pad, in this case.

Electronic crossovers really work well for getting more sound pressure, but its debatable whether they help sound quality. Some speakers are of such disparate design that sometimes there is no other way.

In this case if you don't use an electronic crossover the amp that you use for the midrange will have to play the bass as well, so that amp will not likely be able to play nearly as loud. Your tweeter is so much more efficient that you can drive it as an afterthought by any amplifier that can drive the mids. Does your crossover have a balanced output for the midrange amplifier? Can it be set up as a two-way?
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