4 amplifiers to drive 1 pair of speakers?

Hi 

I am using kef reference 5 with recommended 50-400W needed to power it. Most of the impedence on the chart is around 4ohm instead of 8 ohms. Lowest dips to 3.2 ohms. Although it is 90db at 8 ohms, there are 4 woofers, 1 tweeter and 1 midrange on each speaker - hence may require more power/current. 

From what I understand tube amps (or at least SET amps - not 100% applicable here as they are PP) should not be pushed past their 25% limit to have a good sound.Hence for a 18W 300b PP monoblock amplfier to drive my speakers will likely be insufficient. Hence exploration of 4 amplifiers and whether anyone has tried it before/if it is feasible. 

@scchengmus what do you mean by power ratio calculation? Why will there be equipment failure? :) sorry am not well versed in that

Thanks

Hi @atmasphere 

Thanks for sharing the idea on monostrapping! Was reading up on it. How about what if I do not monostrap? Monostrap kind of puts the amplifiers in series if Im not wrong? So if I place the amplifiers at parrallel will they actually sound more musical/less harsh and heavy handed?

Thanks

I can see maybe 2 at most ,it creates too many issues the input sensitivity of each amp is different if not the same ,
a amp for the bass for sure a quality SS amp, tom tube or SS 
and a Tube preamp , SS amp is widely used or tube .
your speakers will determine this too by their efficiency
thrn if you have to add a external crossover  that more added in the circuit which dips never better less sonic purity ,less is always better in 5he signal path . No mention of the speakers being used 
and space size needed , if monitors ,then judt get a good powered sub with nice modern app like a Svs ultra 16, or Svs- SB 3000 sub. Then you only need an amp on top .

thegreenman, excellent job of thinking creatively in terms of system setup! Most people do not have the vision to see such potential. It is through exploration of options that would not necessarily be considered that some very cool things can happen. Note well: multiplicity of amps does not equate with superior results. Many factors go into the result, and simple higher quantity of amp channels is no guarantee of superior sound. 

You have been given superlative advice from seasoned veterans that it may not be an ideal setup. In general, over many years of building hundreds of systems, it has not been the quantity of amp channels, but the quality, i.e. not only the build quality and preference for SS or Tube, but Watts and current delivery, that has been THE most important aspect. 

I have many times tried unusual configurations such as splitting the pre output in order to do additional channels, and nearly always a simply superior amp yields a much preferable result to use of several amps. There is a HUGE difference in systems set up with even one stereo amp and bi-wiring versus multiplication of lesser amps, or additional amp channels. That may sound counter-intuitive to you, but you need to trust me and others who are guiding you.  :) 

Listen to the old warriors; they know whereof they speak.  :) Personally, I would not dream of using so little power on any nearly any speaker, regardless of its efficiency. I have speakers above 90dB sensitivity, and I drive them with hundreds of Watts. I would not wish to drop down in power, because even they would sound relatively anemic in comparison. You may disagree now, but that is lack of experience. You are absolutely wasting those speakers with 18Wpc.  :(  You are getting nothing close to what they could do, and with zero loss of beauty of tubes.  

You will get a fresh take on amps in my upcoming article at Dagogo.com in regard to the Legacy Audio i.V4 Ultra Amplifier. The world is changing, and in this case, much for the better!  

Now, there will come along someone who will suggest i have it all wrong, 
that even the 18Wpc is "plenty" to drive the speakers. True. Is it superior, the best you can do? No, not even close, imo. Of course, opinions will vary, and you must choose your authority - and get your results.  :) 

Was reading up on it. How about what if I do not monostrap? Monostrap kind of puts the amplifiers in series if Im not wrong? So if I place the amplifiers at parrallel will they actually sound more musical/less harsh and heavy handed?

I think you'll find that by monostrapping you'll be able to drive the speakers far more easily! The only tricky bit it you need two identical stereo amps to pull it off.


BTW instructions on how to do this are in the Dynaco ST70 manual. I used to run monostrapped ST70s when I was in college.


BTW you **can't** use this technique with solid state amps- you'll blow them up!! It is possible to monostrap them too, but the technique is entirely different.