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
BAT VK-60. Could probably pick one up for around $1,750 used. If it turns out that you need more power, it can easily be bridged to 120 watts. You would then, of course, need another amp for the tweeter, but a smaller amp, about 2 watts, ought to take care it.
Thank you all for your replies! In regards to J_bailey's suggestion I have been doing some thinking and being that the speakers that I am going with have a large difference in their efficiency would it be a better/smarter idea to go with 3 different amps for my situation? Have low power amp for the tweeter (SPL: 109 dB 1W/1m) , a more powerful amp for the mids (SPL: 86 dB 1W/1m) and then of course the ridiculously powerful Krell for my subs? Let me know your thoughts and thanks again for the replies guys!!
It sounds like you might be in over your head. Wouldn't a simpler system result in a better sound? That has been my experience.
With all due respect, this sounds like a horribly overly complex setup, which would be difficult to wrap your arms around.

I recommend stepping back to see the forest from the trees. For starters, are you using this rig mostly for movies in surround, multichannel music only, or 2 channel music? IME, most 5.1,7.1 etc. has most music from front mains, and the center channel is mainly spoken dialogue. Any rig that is bi or tri-amped is going to rely on expert knowledge of crossovers etc. to get any kind of balance. You mention everything except what your speakers are. That would help.
Can we translate your question to something akin to,

"I have X speakers in a HT setup w/JL subs, driven by Krells. What amp would make sense for the other 5 channels?" Cheers,
Spencer
If you have 3 midrange drivers in each channel I would put them in series since you have an electronic crossover- that will make them easier for a tube amp to drive.

However Jim and Spencer are both making good points- getting the system to blend and work together as a unit is likely your biggest challenge.
I don't feel like I am in over my head here. I am just trying to put together a system that utilizes the advantages of the different amplifier technologies. I don't have $30,000.00 to spend on a tube amp that can push my subs so I have to use SS for the low frequencies. As for the mids and highs, I would like to use tubes as they produce a warmer better quality sound (according to most reviews) and since my mids and tweeters are more efficient than my subs I think that I can us a less powerful tube amp (mainly one that I can actually afford) to drive these speakers. The reason for wanting them on their own isolated channels is so that I have more granularity in tuning each of the speakers so they sound right in the room that I have them. I do agree that a simpler system more often then not sounds better then one of extreme complexity but I would like to try to put one together that does sound good as I have a severe case of audiophilia and thoroughly enjoy messing with this type of stuff for hours on end. I am actually so into it that I have built all of my speaker enclosures using various software to tune each of the different drivers. I am not sure of how or if I even can but I would like to post a picture of my sub woofer box on here and I think once you see that you will agree that I am not in over my head with this... :-) So I guess the question remains, what would be a good tube amp for each of my speakers, I have 2 Morel's 531's which are rated at SPL: 86 dB 1W/1m and I have one tweeter PylePro witch is rated at SPL: 109 dB 1W/1m. So obviously the amp for the tweeter does not need to be very powerful at all but the one for the mids will need to be somewhat powerful. Since I would like to use two different amps to drive these what would you guys recommend for each of the stated speakers? Thanks again for any and all input!

Also let me know how to post pics if that is even possible as I would like to show you all my sub enclosure....

Mello
What is the cutoff frequency of the sub? That will make a big difference as to how much power the mids will need. Can you rearrange the drivers in that box so that they are in series?
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.
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
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.
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
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?
yea the cross over has a balanced output for the midrange amp. I can actually make it pretty much any range of sound frequency that I want it to. I was planning on setting up the midrange amp to receive a range from 80hz to 3.5khz and then letting the tweeter take it from there.
It sounds like you ideally you'd like a pair of amps that have lots of power on one channel, and just a little on the other -so you can run the high power on the mids, and the low power on the tweeter?
That would be ideal or even one amp that has 2 high power channels for the mids and another with 2 low power channels for the tweeters. Either way I would like to run tubes in both cases.
I've yet to see any amplifier that is low power on one side and high on the other.

We make a stereo 30/w channel amp called the S-30 and a several monoblocks. If you put the mids all in series our smallest monoblock, the M-60, may well make enough power to do the job- about 80 watts per channel.

Both have true balanced inputs. The S-30 may well be the lowest power tube amp to feature true balanced inputs.