Help KEF 104/2 what amp do I need to drive them?


I recently picked up a pair of KEF 104/2's at a local sale. I have had these hooked up to a new yamaha receiver (around 100 watts)and they sound pretty decent. However, from the little information I have been able to find on these speakers it seems that they are rather picky and like a strong amp. I am trying to find an amp that will drive these to their full potential. Does anyone have any recomendations or past experience?

I am looking to spend no more than $500 on the amp right now and I am hoping to buy used. I have seen several 125 watt B&K amps online. I was also thinking about a used NAD amp. Can someone please help me out?

Thanks!

Madison
madmanbmw
I think these speaker have low impedance at low frequencies, so they need a lot of current delivery ... that's probably where the yamaha falls over.

At $500 it's tricky to find good current delivery, but NAD and rotel would be the first names that come to my mind. If your receiver has preamp outputs just get a poweramp and you could get a better preamp later.

If you can find one then a used Audiolab 8000P power amp would work well and is a step up from NAD/rotel.

And if you ever find a used Mission Cyrus 2 with the PSX power supply then that would work a treat, but they are rare as hens teeth.

In fact here's one that looks good.

http://cls.audiogon.com/cgi-bin/cls.pl?ampstran&1124652835
I agree Cyrus 2 is a good amp but I have a feeling that it would run out of steam if pushed too much. It entirely depends on your listening habits. If you do not play it loud the Cyrus would be a great amp.

I have heard many NAD amps and also own one (25 watter) and I have a feeling that it may be a great all rounder for your 104, I have the Kef Reference 2 which is a direct decendant of the 104 in terms of woofer configuration, I can tell you that the Kef is a bear to drive. They needs loads of current and at your budget your best bet would be something like the NAD 370 used or even 372 if you can get hold of within your budget. NAD has very good reputation when it comes to budget equipment. Rotel as already pointed out is also a great chice to drive the KEF's but they are slightly forward sounding compared to the NAD. They tend to be slightly more expensive as well compared to NAD.

Good Luck with your hunting for an amp!
The Cyrus 2 would need a PSX to really sing with KEFs.

In England a friend of mine ran Kef 103/4 with a Cyrus 2 / PSX and he could blow the walls off in a large living room.

But they're so rare it's probably a non-issue.
I may have a friend willing to give me a deal on the Krell 300i integrated amp. I think it is 125w per channel for stereo but other than that I do not know much.

How would this do with the KEFs?

thanks
madison
Could you try it out? I have no personal experience with Krell, but unless someone here posts a response based directly on experience with the 300i driving 104/2s I would ask your friend if they mind you doing a quick home demo.
I have done extesive listening with the Kef/Krell combo and I was not impressed with the 300i, very cold sounding amp. The current setup that I have is Quad 606II which sounds far better with the Kef's, the NAD has a sound closer to Quad and Cyrus than Krell. Besides the 300i was not a good model, infact some think it was the biggest mistake Krell made. Krell was also very quick to come up with an upgraded one. If any other Krell was being discussed my opinion would not be same.

If it is easily available to you for audition, by all means try it, you can make your own judgement.
A pair of Kef 104.2 were my first speakers and I attempted to pair them with a Hafler DH 500......not good...under powered...especially at "party volume".

Just some info on what doesn't work.
Thanks for the advice guys. I am looking into the brands you all suggested. Does anyone else have any more advice and/or experience with these speakers?

madison
mtmajor@uiuc.edu
The KEF 104/2 is a true high-end speaker that can compete with the best on the market with mods and the right amplification. It sounds better and better with higher-power and lower impedance amps. My modified pair were called "killer speakers" at CES this year (dont ask - the mods are $6K). I use modified Parasound JC-1's to drive them - delivers ~1000W/chnl into 3 ohms.

Steve N.
Empirical Audio
Manufacturer/modder
MMBMW, if you don't mind running Class A amps, they run hot and you normally wouldn't leave them on all the time...like tube amps. I would suggest waiting for a Forte Model 4 or 4A. I am very familiar with the Kef "sound" and in particular your speakers from their inception as the plain old 104 ( had the originals when I lived in Germany). I have owned the Forte amp and it's bass with match your Kef bass perfectly. This amp is also very musical and non-fatiguing, much like how the Brits like their sound. You may have to shell out another $100 or even $200 over your $500 budget, but it would be worth it. Synergy is always the key to good music and the Forte and Kef combo is a perfect match. Don't let the 40 wpc fool you, this amp is pure Class A and powerful! I'd be patient and wait for one to pop up on the Gon. My 2 cents, good luck.
Having owned the 104.2 for some 5 years now, I wouldn’t call them particularly picky. Like most good designs they do respond to better amplification, but, as your experience shows, they will sound decent with even mediocre amplification. I’ve run mine with everything from Rotel receivers to a Bryston 4B to a Rega Mira integrated. The most notable improvement from better amplification is in the bass, which can sound loose and wooly if underpowered.

The Cyrus is a good recommendation, though a bit hard to find here in the US. The Rega really surprised me with it’s relatively low power rating. It did an excellent job (especially for $400!) controlling the bass while extending the highs as well as the Kefs’ soundstage. Considering that you haven’t budgeted funds for a preamp, I’d go the integrated route for now. Solid offerings from Rega, Cambridge, Rotel, etc... are within your budget.
I dont really have to go integrated, though that is an option. A used NAD 370 integrated seems pretty appealing since I dont plan on adding a sub anytime soon. The $500 price budget was just a rough idea. I can go higher or lower if I would notice a big difference or I could spend more if I was getting a really good deal. I just want to get the best sound for a good price and seperates are by no means out of the question.

Since I live in a rural area it is hard to test different amps with the speakers and other than your suggestions I will be buying blind. I want to make sure I get enough power for these speakers that I will never desire anymore. I do not need to have the best amp but I want the speakers to perform at 99.9% of their potential.

Madison
How would a Rotel 990BX perform with these. 300 watts into 4 ohms.

Madison
mtmajor@uiuc.edu
Quadophile,

No, I am looking for amps on Audiogon and on ebay. Sadly there is no place around me that carries used equipment.

What do people think about B&K and Adcom?

madison
I have never heard B&K amps so cannot help you there, but, yes I am familiar with Adcom, I never liked them personally even though I have heard them in different setups as well as having different power ratings. For the amount of money one pays to buy Adcom there is always better ones available for the same price.

I hope it helps.
I have been using a Leak Stereo 20 with my 104/2 for the last 5 years and can not believe how synergistic the pair is.
Has anyone ever used a tube amplifier to drive KEF 104/2 speakers? If so what did you use? I'm just curious. I'm thinking I may try a Jolida JD-502P with a quad of Tung Sol KT-120 tubes in place of the 6550 tubes it comes with. Preamp would be an Accuphase C-200.
I had some KEF 104.2's in the garage, planning to give away. So to test them, I hooked them up to an VAC Avatar integrated (EL34 tubes) running in triode mode,(27 wpc) and it sounded so good that it replaced what I had, and is still producing endorphins.
I've been using a Dared 300b tube amp set for years, with great results. These are very affordable. Efficient speakers.
If you can stretch your budget just a bit, I'd imagine a used McCormack would work very nicely indeed.
I have a friend with 104/2's who uses an Adcom GFA-555 with them. He loves the combination but is admittedly not an audiophile.
I also used to run my 104/2's with that Adcom back in the early 90's! By the time I reached my all-tube all-the-time system the Kef's had been long replaced by my Spendor S100's! I remember how highly-acclaimed that Adcom was. At the time I was just a rookie at all this, to my ears the amp sounded fine, I wonder how it (GFA-555) would rate today?

I have a pair of Kef 105-2 and drive them with a Chord 4000 spm sounds real nice.
madman,

Just curious if you ever settled with an amp for those KEF? I have a pair myself and was wondering which amp you decided on and how they sound?
I had lost track of this thread. Thanks for updating it Itsmetn. After the follow-up replies to this thread after mine I did hook up the Jolida JD-502P to the KEF 104/2s and the music was awesome. Whether it was Tung Sol KT-120s, JJ KT-88s, or GE 6550s in the Jolida the music was awesome. Also for a bit I hooked up a pair of re-built Response Audio BellaExtreme 60 monoblocks. These monoblocks have a pair of 6C33C tubes in each amp. The music was pretty awesome also with these amps and the KEF 104/2s.