Amps for KEF Blade 2

I am looking for advice from owners or dealers of the KEF Blade 2 loudspeakers. I am concerned my current pair of amps will not be sufficient for the B2s because of an article written about the original Blades published on July 5, 2013 in The Absolute Sound:

"The Blades have a nasty kick in their crossover that will suck an amplifier dry quicker than a student downing free tequila shots ... Just don’t be tempted to cheapskate on the driving amps, or you’ll live to regret it. Tube amps at least have an output transformer to hide behind, but when the Blades suck out a solid-state design, they celebrate by spotlighting their tweeter something chronic. To give you some idea of the lengths required, the otherwise excellent Rowland 625 [550 watts into 4 Ohms] wasn’t up to the job, it taking a pair of the 725 monoblocs [650 watts into 4 Ohms] to restore order. "

Are the Blade 2s just as demanding as the original Blades in terms of amplification? I would guess not due to the smaller 6.5 inch woofers, but this is just an uneducated guess. I own a pair of Benchmark AHB2 amps, which according to the manufacturer produce “a little over 500 watts into 4 Ohms”. Will this be enough?
Stereophile has a full set of measurements on the Blade 2 and it primarily shows the speaker requiring full 4 ohm stability with an ability to be fully stable to a 3.2 ohm load. This will simply require an amplifier with adequate current capability. As an example, some of the older ASP1000 based amps did poorly with lower lower impedance speakers than their ASP500 counterparts on some speaker models. The reason was due to the first generation higher power amplifier apparently being less comfortable in dropping below 4 ohm than its lower specified counterpart.

In terms of the Rowland, it does specify near doubling of output at half impedance with the 725 mono blocks as compared to the 625. Most of this load is below 200hz and rises to 6 ohm nominal above it. This could explain the spotlighting phenomenon since we know the B2 goes as low as 3.2 ohm in this area. My suggestion is to try and mate amplifiers that offer 2 ohm stable output in order to prevent the amplifier going anywhere near its potential current reserve. One suggestion would be some of the Pass Labs models, as some are capable of power into 2 ohm loads without much stress. This factor is tough to know until you get the amp on the bench. Even then, there is something to be said about overall synergy.  
Thanks mmeysarosh for the informative post. I decided to contact Benchmark about their AHB2 amps driving the KEF B2s and this is what they wrote back to me:

"This is from engineering. This is actually a very easy speaker to drive in mono mode. It is a nice design with well-controlled impedance curves. There will be 6.0 dB more headroom in mono mode with this speaker. The AHB2 will have current to spare when driving this speaker in mono.

Max SPL in mono is 115.9 dB (ignoring power compression)
Max SPL in Stereo is 110.1 dB (ignoring power compression)

Typically you will need to subtract a dB or 2 to account for power compression."

It’s been a very long time since I took college physics so I can’t say I thorougly understand everything that the both of you wrote, however, I do understand "current to spare"! In conclusion, I’m still not sure if the B2s are easier to drive than the original Blades but, it appears my amps will be able to handle the B2s so I suppose I should be satisfied with that answer.

I did see some of the specs on their website and they do specify increasing power output at 3 ohm load, which indicates amplifier design with current capability in mind.

While the the power output isn't able to drive the speaker to its max SPL, my take being that you'll give up before either amp or speaker do.

Overall it sounds as if you have a capable partner. I brought up some of those ASP1000 class D amps as they doubled output going from 8 to 4 ohm impedance, but quickly fell apart anywhere below that. The speaker in question was the Revel Salon2, which is also current happy design with lower efficiency in comparison to the B2. So you really want to get a clear answer if the design can dip to 3 ohm or even 2 ohm. Which is was you do have with your current amp.
When I auditioned the Blade 2, it was paired with a Chord SPM 5000 and did it quite well.  If you want an amp stable to 1 ohm, you can look at the Electrocompaniet Nemo monoblocks.   Those can drive anything you can throw at it.

It has been a year since the last post here. I was wondering how you liked the AHB2 with your Blade 2? What is the rest of your system?

I am all over the map on DAC | Pre | Amp choices for the Blades (for my living room). I am going to try and listen to the Theta Prometheus, Bryston 7BSST3, and the AHB2 with the Blades . If I go this route I am thinking of something like a Briscati M12 (includes DAC + analog volume + soon to be Roon Ready via ethernet).

The other option which I think will definitely work great is getting high quality separates for the Blades. However, there will be a substantial increase in costs doing this. Your approach of using the AHB2 is something I thought might be a way to get around high cost amps for the Blades.
I've been planning for Blade 2s when I consolidate my two setups.  I plan to keep either the new Ayre VX-5 Twenty ([email protected]Ω, [email protected]Ω) or the Parasound JC1 monoblocks ([email protected]Ω, [email protected]Ω) and use an integrated for the LS50s.  Will either of those amps have trouble driving Blade 2s?  I use the VX-5 with a KX-5 Twenty preamp and the JC 1s with a JC 2 BP if that's relevant.

Fantastic together. I have been on the audiophile merry go round for more than 25 years. I use a Mac mini into a PS Audio DirectStream DAC directly into the amps. I’m done. This is my “forever system”. Good luck to all of you and merry Christmas!
Thanks for the feedback. I will have to do the home demo with the Benchmark amps. I was also thinking of the PS Audio DS or the Briscati M12 (soon to include ROON via ethernet).

I think the Ayre maybe a little weak for the Blades from what I have read about the Blades.The JC1 is a popular amp for the Blades. I heard the Hegel 360 integrated with the Blades and it can drive it well. Another alternative amp, and 1 I am considering along with the Benchmark, is the Theta Prometheus. A fellow A’Goner sent me an email indicating that it was a phenomenal combo with the Blades. A well known KEF rep came to his house and said it was one of the best Blade + amp combos he had ever heard. I won’t get into details of the email since it was a private message. The Theta measures similar to the Benchmark but 2x the cost..

I also have the KEF LS50 and I am amazed at how good it now sounds with my new integrated, a PeachTree Nova 150 ($1500). My prior amp, a Parasound A23, never sounded this good with the LS50,


I was disappointed with the Parasound A23 driving the LS50s, but the A21sounded very good.

I replaced a Proceed HAP 2 with JC 1 monoblocks to drive KEF Reference 107/2s.  The improvement in sound wasn't subtle.  The JC 1s really made the 107/2s sing.

Without too much trouble I could try the Ayre KX-5 Twenty preamp with the JC 1s and 107/2s, and it's something I should do.  OTOH, perhaps I should just keep my beloved 107/2s and forget the Blade 2s.

I only noticed today that you had asked me about whether I had the Blades in a previous post. Sorry for not responding. I do not own them yet but today I have the money to buy them (worked a 2nd job for them). So some time in 2018 I will buy them.

I am actually now going for the Blades for my office because I have a new baby (who is very active at 19 months) and I am seeing that the living room could be problematic. Another poster on A’Gon related that he was able to get the Blades to sound good in a 14 x 13 room so that gives me hope for the office.

Just as an FYI, I have a few choices in electronics to figure out from the following list:

1) [PS Audio DS DAC or Mola Mola Tambaqui DAC] + MD 102 Analog Tuner + new Luxman 509x integrated. Not sure if it has enough power, but most reviewers state that Luxman underreports the power specs. I we see soon enough.

2) Briscati M12 (DAC + analog volume) + MD 102 Analog Tuner + [Theta Prometheus or Benchmark AHB2 or Luxman m900u or Briscati M15]

3) Mola Mola Tambaqui DAC (cannot use my MD 102 tuner here) + [Theta Prometheus or Benchmark AHB2 or Luxman m900u or Briscati M15]. Sell the tuner and listen to my beloved KRCW via internet.

I had a large list of high end integrated’s I was looking at but I am starting to see that there are a few really high quality DACs with good volume control or preamps with built in DACs.

Guys as a Blade dealer having both the JC 1, Electrcompaniet, Chord and T+A electronics on the Blades.

Here is our take, the JC 1 were okay amplifiers, not magical and not worth the hype, the Electrcompaniet AW 400 were fantastic and dramatically outperformed the Parasounds, the AW 400 also came down in price to $12k vs the nearly $10k price for the JC1.

A pair of Chord SPM 650 monos were a bit better, and the $32k Chord SPM 1400 were amazing.

We lost the Chord line due to not enough sales, brought in the T+A electronics and quite frankly outperformed the Chord stuff.

We have used the big T+A amp and preamp with the Blades and the sound is amazing! Huge soundstage, fast, tight bass, warm midrange, fantastic stuff.

If you are on the East Coast come in for a listen. 

Dave and Troy
Audio Doctor NJ

For those guys who say yeah right prove it here you can see all the gear we tried with the Blades: ( notice the Electros the Chord and the JC 1 same setup then replace the 207 with the Blades

now see the Blades in the same space as the 207.2

Long story short, the T+A gear was the best solid state we ever ran with the Blades, as well as the Persona 9H

We also tried the Thrax gear, the Devialet D400 monos, CJ Arts and a few others the T+A gear has so far come the closest to the mega dollar gear for a fraction of the price which is why we recommend it so highly.

Dave and Troy
Audio Doctor NJ
I heard the Blade Two's at the LA Audio Show with the Hegel H360 and it was surprisingly good. A $6k retail integrated driving a speaker of this magnitude may indicate the load is not all that difficult; just a guess on my belhalf. I'm sure there are better pairings, but for the cost, it was really pretty good.
Pokey sure they will sound good, but good isn't amazing. When you use uber class electronics the speakers become much more holographic and the sound stage gains huge amounts of width and depth. 

There are tons of very capable components but you have to hear an uber class component and you will know just what special is.

We demoed a $11k T+A R2500 integrated amplifier and it just was a relevation compared to all the other great intergrated amplifiers we had in that room. 

The T+A had a sense of rhythemic drive that the others didn't have, macro dynamics, along with a huge three dimensional soundstage, superior resolution and bass definition. 

The result is that this piece just made music intoxicating and you were drawn in.

When you hear a component which does this you will understand the world of what makes great from good. 

Think of it as tasting the highest quality freshest ice cream where you can taste all the components that make up the flavor, distinctly and yet enjoy the blended quality of the taste, and you can experience the creamy smoothness. 

Whether you are comparing high end audio gear, fine food, Scotch or other things of this type there are those stealler products that you can just expereience their superior refinement. 

Dave and Troy
Audio Doctor NJ
I think you are missing the point of pokey's comments.  
No Ghosthouse, I am not. Pokey has not had the opportunity to compare a product at the Hegel level to the T+A on the same speakers like what we did when we were shopping for replacment electronics. 

We are always amazed at how good some reasonably priced components can sound, the difference is are you getting all you can out of the speakers?

Dave and Troy
Audio Doctor NJ
I think you did.  He wasn't touting the Hegel as endgame electronics for the Blades, merely commenting that the sound was good even given the disparity in price between that speaker and those electronics - possibly indicating the Blades are electronics-friendly.  Regarding your comments, I've no doubt the T+A brand is a well-qualified member of the highest echelon of audio gear.    
Hi Dave,

I appreciate your comments. But in this case, ghosthouse better understood the essence of my comments. Yes, I have not heard the T+A gear with Blade Two's, just the Hegel H360 and that is what I was trying to convey.

I have heard much of the T+A HV series gear with Wilson and liked it alot. Had hoped to hear it with the Persona's, based on your comments, a few months ago, but when I was at the dealer the HV integrated was on loan.
own b2 for 2 yrs. driven by emotiva dxa1 GEN 2 and emotiva dc1 stealth dac / pre.

love the results. no issues whatsoever.

upgrading to blades and plan to use same components
Jrfa, sure you may love the results but without auditioning  other gear on the speakers we don't think you  are scratching their true potential.

We have heard startling differences between $15k and $35k digital front ends how do you think a $500 dac will sound compared to such expensive digital front ends? N

Most people do find the Emotiva stuff to be great for the price but great for the price doesn't necessarily mean it perfoms great.

Personally we would never recommend such pairings as you are dramatically undercutting what the speakers can really sound like. 

Dave and Troy
Audio Doctor NJ
Post removed 
d2girls you talk to much without adding anything. Please keep to the topic which is Kef Blades.  Which we have on display and have been working with them since they premiered on the market.

We have been working with KEF for quite a number of years and have paired them or tested them, with Hegel, Luxman, Parasound, Devialet, Norma, Naim, Coda, Micromega, Anthem, Nuforce, Electrcompaniet, Chord, Merrill Audio, Manly Labs, CJ, and T+A audio.

As per shitty store, most of the people who have been here have commented on our remarkably diverse selection.

it is a shame that you would not be allowed to set foot in our "shitty store
 which has one of the best collections of gear in the New York Metro area.

Dave and Troy
Audio Doctor NJ

Last point D2girls, please check our Google reviews of people who have actually been to our shop, many people who have shopped with us have said we have a wider selection of gear then anyone in the state of NJ and we have a larger and more diverse collection of gear than the NY City stores.,,

Who in the New York area has a wider selection of affordable high performance  speakers: we have: KEF, Dali, Paradigm, PSB, ATC, Quad, Elac, Cabasse, Rethem, Legacy and we are playing with Bache. 

Digital where in the area can you hear: T+A, Lumin, Aurender, Baetis, Naim, Mytek, Aqua Hifi, Light Harmonic, M2 Tech, and a few others.

Electronics: Naim, Manly, CJ, T+A, Electrocompaniet, Anthem, Unison Research, Mytek, Nuprime, Micromega, Parasound, Nad, Nad Masters, Cary Audio, Synthesis, Audio Control and a few others. 

d2girls, your attitude is appalling, you don't know us, never directly talked with us or have visited our shop.

We have many followers here on Audiogon, who follow our posts who find our perspectives and experience to be very beneficial.

Dave and Troy
Audio Doctor NJ
Conversely, many find you pompous, self absorbed, and long winded concerned only with the an inherent interest of financial gain couched within the guise of “providing information based on lengthy experience “

The door swings in 2 directions. 
yes wcfell we are selling truck loads of gear all over the country.

Our responses are usually short unless we are being attacked which requires long rebuttals sometimes to prove a point

Again wcfell unless you have personal experience with us how do you base your opinion on forum posts?

Most intelligent people seek knowledge from the source rather than relying on heresay.

Good luck to you.

Dave and Troy
Audio Doctor NJ
Post removed 
Post removed 
Thanks again for proving my point. 
I don’t need good luck though. 
Wcfeil just read some of your responses.

A forum is a place to exchange ideas on the topic at hand.

Read all 7 of your responses almost everyone of them is off topic.

In the future add a direct ancedotal story or raise a point that furthers the conversation I am quite sure most people are turned off by your immature drivel.

Please tell people your direct experience with Kef Blades do you own a pair?

We do. 

Dave and Troy
Audio Doctor NJ
KEF uses Electrocompaniet Nemo monoblocks to drive the Blades in their factory museum:

They might know a little something about driving them....
KEF uses a variety of amps to demo the Blades. The latest love connection seems to be with Hegel. The new Hegel 590 integrated and the Blade have some sort of development deal.
I've heard the KEF Blade 2 with Hegel H360 and their reference separates and it was very good on both. Also heard the big Blade with the Luxman 900 separates and again it was really good. Not sure which I liked best since that was around 6-8 months apart. I was surprised how good the H360 was with the Blade 2s though.
I have the h360 and used it to drive a pair of salon 2's which it did nicely, but not dynamically and that's a deal breaker for me. When I suggested bi-amping horizontally the crowd' overall said it wouldn't make a difference? My h360 isn't going anywhere and I expect the Blades will sound the same, as in 'good but limited'. What do you guy's think? if I bought a pair of steller 700's to run the bass and the hegel on top would that be enough headroom to let these sing? 
I have had the Blades for one week. Currently running on woefully under-powered NAD M3 integrated (described as dual mono block design) and actually the Kefs sound rather good.