I have a pair of Sonic Frontiers SFM 75s that have bonded with the LS 50s extremely well. Tube monoblocks FTW. ;)
Best amp for KEF LS50
Looking for best possible amplifier for KEF LS50s. I have tried Parasound Halo A23, Benchmark's new amp and ,currently the Audio Alchemy DPA-1. So far, Audio Alchemy sounds the best, Parasound next and Benchmark the least satisfying, But, I'm still wanting a better match. I'm looking under $3000, tubes or solid state, new or used, and hopefully not huge and weighing a ton. I would really appreciate recommendations.
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I just completed a Pass DIY amplifier project based on using NOS Sony 2SK82 and 2SJ28 VFETs as a complimentary pair in a push-pull Class A amp (https://www.diyaudio.com/forums/pass-labs/276711-sony-vfet-amplifier-2-a.html?). Even though this amp is only rated at a nominal 15 watts per channel into 8 ohms and 20 watts per channel into 4 ohms, this is one of the finest amp pairings I have heard with the KEF LS50s. This amp has a relatively high damping factor of 45, and I believe this contributes to the synergy between this amp and the LS50’s. With my Audio Research LS7 tube line stage, I have no problems filling my living room with tonally rich music presented in a huge holographic soundstage that I previously thought was only possible with tube amps. Combined with the spectacular imaging of the LS50’s, I am treated to very engaging music events every time I play analog or digital tracks. I listen to a wide range of music from early choral to jazz to classic rock nd blues. In fact, I was jamming to The Who’s “Live at Leeds” earlier today along with Morton Gould and His Orchestra performing Copland’s “Billy the Kid” and Grofe’s “Grand Canyon Suite.” Unfortunately, the Sony VFETs are near-unobtainium, but Nelson Pass does build First Watt Class A amplifiers using new production equivalent (maybe even better) Semi South Static Induction Transistors (SITs). His SIT series of First Watt amplifiers have received excellent reviews and they are worth auditioning with the KEF LS50’s in an appropriately set-up system. |
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I see I have commented on this thread in the past so I thought I would update. 1) Paraound A23 + LS50 : I thought this was good combo but easily bettered by the next 2 amps I bought. 2) Second best was Peachtree Nova 150 + LS50. Lot of details, not harsh. Can listen for hours. The iPhone USB connection is surprising good with iTunes. I normally listen to FLAC or FM radio. 3) The Benchmark AHB2 + LS50 is my best combo, Just clear and deep view into the music. |
I just purchased a used Pass Labs INT-30A integrated amp and will try it with my LS50s. My only fear is the Pass Labs is a 30wpc Class A amplifier and my small home office where the LS50s reside could get hot! Doesn’t help that it is summer and I live in Florida. If it gets to hot int the home office I will try it in my main system. |
I've heard the LS50s a number of times. The first time was the best; it was at THE Show at Newport when they premiered. They were paired with Parasound separates that were approx $8-9k and a laptop for source. Very nice sound, but a lot of $$ for a $1,500 speaker. Then heard them with Parasound again, but an integrated (not the big one) and the sound was not near as good as with the separates. One thing I've heard over and over is the LS50s need lots of power. Too bad they don't have a more benign impedance curve. |
LS50 is a not an easy speaker to drive as it spends much of its low mid range and bass frequencies between 6ohm and 4 ohm. Solid state amps that fail to provide adequate current into those lower impedance range would result in higher frequencies standing out, hence sounding 'bright'. The best kind of amp to drive LS50 is one that can double power from 8ohm to 4ohm that could either be a Class AB or Class D if you're into solid state. For solid state, not to over spend way beyond price range of your speakers I would recommend Marantz HD-AMP1 or PS Audio S300, both have really great used price. I read great things about NAD 3020 but never used myself. I paired the Marantz with my B&W 805D3 with good results. Otherwise, tube amps do handle lower impedance better than most solid state in your price range. If you're new to tube amp, picking up a used Yaqin KT88 or EL34 based amp from Amazon.com or here on Audiogon could be a good starting point. |
Bigridge, What type of sound do you like? The reason I ask is because I am close to buying the Benchmark amp to go with my KEF LS50 and Benchmark DAC2. Your dissatisfaction with the Benchmark is surprising to read since all the prior reports I have read were very positive. What did you not like about the Benchmark? Hegel amp/integrated are being demo with KEF speakers at shows, both the LS50 and Blade2. You may want to check out a Hegel. The new Bryston 3B-SST3 is also another amp to consider. I heard the new Wyred4Sound amp with the KEF Reference 1 recently and it sounded great. https://wyred4sound.com/products/power-amps Also check out the DARKO web site which has a lot of reviews of amps with the LS50. http://www.digitalaudioreview.net/category/reviews/ BTW - I am currently using a Parasound A23 amp with the KEF LS50, but this amp is dying a slow death and needs to be replaced. |
Sounds like it’s time to try tubes. Check out the Rogue! http://www.needledoctor.com/Rogue-Audio-Cronus-Magnum-II-Integrated-Amp |