Tube/amp ?

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I recently called John Atkinson a numbskull (Mikey was not happy) because he implies that a speaker's frequency response will follow its impedance curve when used with an amplifier with low damping factor. This is not true. Speakers, even electrostatics, operate on power. Sure, put a voltmeter across the terminals of MLs and it would show decreased high frequency response. Put an (ideal) ammeter in series with the speaker it would show a rising HF response. Correct? I have done this with mine (Montis, tube amps w/ 0.7Ω output impedance, compared with solid state): put a microphone in front and measure their response and there is little or no difference.

Power in this case is factor of voltage in speaker terminals. Typical speakers and MLs too are voltage driven thus output SPL will depend on drive voltage which will be affected by output impedance of the source (damping factor & power amplifier). Voltage on speaker terminals is result of voltage division between source and load impedance.
 
Can't say much about newer tube amps, but for vintage gear, I'd recommend Harman/Kardon's Citation II. I've got one that I've mildly upgraded, and it drives my Sequels, full range, very well. I'm not sure what the sensitivity of the Summit's panels are, but the Citation would have no trouble with them. They're very stable and have little trouble driving difficult loads. Find a good one, do some of the common upgrades, such as those that Jim McShane recommends, and you'd be VERY happy.
 
Pneumonic in post number 10, brilliantly, succintly and concisely captures all major points and heads towards a conclusion in the ongoing debate tubes amps versus solid state amps. A treat to read.

Have fun listening to music.
 
Pneumonic in post number 10, brilliantly, succintly and concisely captures all major points and heads towards a conclusion in the ongoing debate tubes amps versus solid state amps. A treat to read.

Have fun listening to music.

You can say that again Spanky!! Very well written post. I'm amazed at the power Summit panels can suck from an amp, Since the meters on my 500wpc continuous @8ohms only show that measurement, I have no idea what it's really doing. When it hits 250 on the peak meters (it has regular and peak for each channel) it is more than enough for my room. I've played with some tube designs, A BAT that I can't remember right now, It was lovely but, no oomph! It was rated about 125wpc IIRC, I love tubes and can't see how you can go wrong with them, great for low level listening sessions with some nice peak headroom on the higher output models. I think if you like the tube sound you might be better off using a tubed preamp and having a solid state amp grunt the muscle these panels need/demand! YMMV
 
Pneumonic in post number 10, brilliantly, succintly and concisely captures all major points and heads towards a conclusion in the ongoing debate tubes amps versus solid state amps. A treat to read.

Glad you found my post useful.

However, I am not so sure that we'll ever reach such a conclusion in this, oftentimes, crazy hobby. :p

Have fun listening to music.

:music:
 
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Cary CAD-211FE on my Summit X's
 
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Amp

Have a chance to get a good deal on a audio research ref 75, do u guys feel this would do a good job driving the summits with out any problems? Thanks
 
Hola Ken. What do your ears tell you? Do you like your new sound? Do you find any distortion with the signal? You are driving only the stat panels. Your new ARC does not uses any power for driving the bass.

Tell us about your finding with the stage, timbre, size of the instruments, vocals, wind instruments, percussion instruments and string instruments. ´

Your ARC is capable to use the new KT-150s power tubes. There is a factory kit for it, if you would like to add a little more power to your amp. But, I assure you that you are safe with the KT-120s. I am using them in my ARC VT-100MK3 and was a very good improved tweak, specially at the mid range section.

Happy listening!
 
Hola Ken. What do your ears tell you? Do you like your new sound? Do you find any distortion with the signal? You are driving only the stat panels. Your new ARC does not uses any power for driving the bass.

Tell us about your finding with the stage, timbre, size of the instruments, vocals, wind instruments, percussion instruments and string instruments. ´

Your ARC is capable to use the new KT-150s power tubes. There is a factory kit for it, if you would like to add a little more power to your amp. But, I assure you that you are safe with the KT-120s. I am using them in my ARC VT-100MK3 and was a very good improved tweak, specially at the mid range section.

Happy listening!

Roberto: sorry if u misunderstood but I have not purchased it yet I was just asking if it was ok to use with the summits? Yes it would be just driving the stat panels.
 
Ken, I have a dear friend with an ARC Ref 75 with a CLXs. They do sound fantastic! Its a great amp. I think that you will love it too.
R.
 
Ken, I have a dear friend with an ARC Ref 75 with a CLXs. They do sound fantastic! Its a great amp. I think that you will love it too.
R.

Hmmmmmm, whilst I consider the Ref75 to be a superb amplifier I do not consider it to be an optimal match for CLX.
That combo would be fine if listening at mid range levels however, as an example when one cranks dB's up to live performance levels you do require at least 150 watts if looking at ARC, with my own previous Ref150 were I to push into the high 80's to 96dB CLX's were drawing 90 to 148 Watts on peaks.

Having now moved to ARC Ref250 SE one can now perceive how often the 150 was running in the RED zone, the new amplifiers bringing percievable improvments accross the whole spectrum.
 
Well if we consider that 75W compared to 150W means full 3dB maximum SPL more, it wouldn't be critical difference for most users. If you really do need that extra power then surely 250W (~5dB)is a meaningful difference. Most of my listening is happening in the <1W zone :cool:
There are other reasons why REF75 might not be optimal for ML, namely relatively high output impedance. OPT also look relatively tiny so they might be driven close to saturation point which is not good for signal control. REF75 however is most likely a sweet sounding amplifier (think about Classic 30) so when operated within its' comfort zone should be quite pleasant to hear.
 

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