Tube amp power?

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khenegar

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I am planning on buying a audio research ref75se power amp. It is rated at 75watts per channel, do u feel that would be adequate to drive my summits for two channel use and also home theater use? Thanks
 
Plenty of power

Nice amp with plenty of headroom no worries at all. Also look at the Balanced audio tech the vk se 60 & 75 plenty of power. The bat amps are incredible from 250"hz and up one of the best amps I've ever heard. The reason I say that is because of the reproduction of the human voice. Also both amps dig deep down in the bass with tons of slam. Can you tell I like them. Both are incredible amps. Also the prima 70 watt monos are awesome as well. Great value have fun. The audio research are incredible as well if I had my choice.
Bat
Ar
Prima
 
Hey khen, 2-channel yes at moderate levels, so no for HT is you like the full on effects from the movie. It's important to remember that tubes put out higher outputs than rated vs. SS and, clip softer. I'm amazed at how much power the Summits can suck from an amp.

I agree with Norway84 about the Bat's, I loved the VK SE70's a buddy had brought over...magical!! I like it loud though in my 16' X 26' room! I hit around the 250w mark on the big SAE meters having a blast! I'd love to have a nice tube amp for another level of sonic bliss. Have fun with your search bud! Craig
 
Been down this road before

Khen, the ARC (or mentioned BAT) are more than adequate for the Summits. That said, I was on this road before with an integrated tube system pulling double duties for stereo and home-theater applications. After living with this integrated system for years, I found:
  1. Tube power for the LR mains give little benefits for movies since the dialogue are concentrated at the center channels.
  2. Unless you're really into music and concert videos, most of the time, the emphasis for movies is on special effects with everything amped up to convey 'impact'. Tube amps, with emphasis on finesse yield very small benefit here, if at all.
  3. I am burning up tubes unnecessarily for HT. In my case, I am looking at a total of 12 EL34 tubes for replacement, I'd rather put them to work for audio instead of HT.
I simplified my system by having a Yamaha soundbar for HT, leaving the Logans as a stereo-only system. Just my 2-cents from the experience I learned with my system, your application and preference will most likely vary from mine.

Good luck
Spike
 
I am planning on buying a audio research ref75se power amp. It is rated at 75watts per channel, do u feel that would be adequate to drive my summits for two channel use and also home theater use? Thanks
Ultimately, the answer depends on how you define adequate.

Without doubt the amp will power your speakers and make music but, will it power your speakers such that it can supply enough output current to properly drive the speakers during low impedance conditions and can it swing enough voltage to play the speakers, to your desired volume level, without pushing your amp beyond its parameters and into non linear mode (ie clipping).

Just being honest here but, unfortunately, short of tossing an oscilloscope on the amp's output to test for such conditions, there is no certain way to to say for sure. You really need to measure it - in your room, attached to your speakers and at the volume level that you listen too, with music representative of what you most listen.
 
A good rule of thumb I've been told is (Tube Amp Wattage) x 3 = Solid State Amp Wattage. Tube Amps produce way more current that SS amps.
 
A good rule of thumb I've been told is (Tube Amp Wattage) x 3 = Solid State Amp Wattage. Tube Amps produce way more current that SS amps.

Really?!

I think it's quite the contrary, tube amps can have huge voltage swing but somewhat limited continuous current capacity. There may be exceptions but generally tube amps have higher output impedance and this is a parameter which has more effect (positive or negative) to sound quality than current output capacity unless driven to absolute limits.
 
Really?!

I think it's quite the contrary, tube amps can have huge voltage swing but somewhat limited continuous current capacity. There may be exceptions but generally tube amps have higher output impedance and this is a parameter which has more effect (positive or negative) to sound quality than current output capacity unless driven to absolute limits.

I'm not certain honestly. I've just always heard that. I've never stopped and looked into it. I had a pair of McIntosh MC75s that I was in the process of restoring, but I sold them and bought a Parasound A23 instead, so I didn't have the chance to compare them.
 
I am planning on buying a audio research ref75se power amp. It is rated at 75watts per channel, do u feel that would be adequate to drive my summits for two channel use and also home theater use? Thanks

I have matched ML with several amp at my "local" store - and even tough Audio Research is a great amp - they don´t match with ML at all - or any ESL for that matter. The impedance match is way too far off. I am surprised that you get positive feedback on this match. this is ABC.
 
I would respectfully suggest you try ARC with other related products and listen again. ARC tube equipment mates very well with ML.

I don´t agree. The impedance match is not a match in heaven.. You will have a rolling-off effect with ARC, maybe with a exception with a the largest tube amps (larger bandwith), but I was thinking of the 75W. Compared to a Gryphon (direct coupled SS) for instance - the differences are huge.

I have myself a rolling off problem with the Macintosh due to the transformers. However, the effect is not that bad compared to some tube-amps.

Of course, I respect anyone that disagrees. However, I think I have the maths on my side. It is difficult to match a ML with an amplifier. The midrange is always best with tubes - but the mismatch in impedance for low and high frequencies (due to the transformer and the varying speaker impedance loads) makes the direct coupled SS always the best match. The problem with SS amps: they sound harsh on very honest ESL speakers - so you need to find a amp between tube and SS. Go figure.. The ARC is best matched with loudspeakers with a stable impedance over the whole frequency area - the very opposite of MLs.

I do love the ARC amps, but not matched with ESL.
 
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I disagree. The low end won't be a problem since the OP is pairing them with Summits, which have a SS amp on the woofers. The ARC will give a beautiful midrange and any roll-off on the high end will probably not be that drastic or detrimental to the sound.
 
I disagree. The low end won't be a problem since the OP is pairing them with Summits, which have a SS amp on the woofers. The ARC will give a beautiful midrange and any roll-off on the high end will probably not be that drastic or detrimental to the sound.

I have been of the same opinion. I was measuring the high frequency roll off - and I didn't find a big difference in regards of loss of high frequencies.

However, the mismatch has another issue which is IMO a worse problem. The mismatch (or "roll-off effect") makes the whole frequency band less than optimal - that makes the soundstage sound more compact. I can to an extent fix this problem on a integrated macintosh by using the EQ, but this is not an option on a tube amp. I am not going to claim that this is an issue for all tube-amps - but I would be aware of this risk when trying to match the ML speakers. I have only tried a few ARC amps as well - but this issue is not "invented" by me - it is well discussed on other sites or even here.

My apologies - I think I have been enough negative for one day. After alle we are discussing two very good brands - but I just believe they dont match well (or at least, some of their products). I understand that several of you may disagree due to - after all - a great sound - but imho a A/B test may reveal some issues.
 
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No need to apologize for offering your perspective, redux. All opinions, positive or negative, can be helpful. Ultimately the OP just has to listen to it in his room and with his associated components to know for sure whether he likes the sound. The rest of us are just guessing based on our own knowledge, experience, and personal tastes. Personally, I love the sound of my CJ 140 tube amp with my Summits, but it's a little beefier than the ARC amp under consideration.
 
I don´t agree. The impedance match is not a match in heaven.. You will have a rolling-off effect with ARC, maybe with a exception with a the largest tube amps (larger bandwith), but I was thinking of the 75W. Compared to a Gryphon (direct coupled SS) for instance - the differences are huge.

I have myself a rolling off problem with the Macintosh due to the transformers. However, the effect is not that bad compared to some tube-amps.

Of course, I respect anyone that disagrees. However, I think I have the maths on my side. It is difficult to match a ML with an amplifier. The midrange is always best with tubes - but the mismatch in impedance for low and high frequencies (due to the transformer and the varying speaker impedance loads) makes the direct coupled SS always the best match. The problem with SS amps: they sound harsh on very honest ESL speakers - so you need to find a amp between tube and SS. Go figure.. The ARC is best matched with loudspeakers with a stable impedance over the whole frequency area - the very opposite of MLs.

I do love the ARC amps, but not matched with ESL.

Do you mean ARC REF75? It might not be optimal for ML, try REF150 instead or some older high wattage models. Output impedance is typically improved as nominal output power is increased, there will be exceptions however.
 
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