Hi Amit,
I truly apologise for being very late in responding.
BTW, as I read your later posts in this thread, I am a bit confused about your own pairing of the Leben CS 300XS amp with the BE-718's. If you are 'sure' the amp would not be able to drive those speakers properly, why are you buying this combo in the first place? There exist a lot of other amps that can drive those speakers or there also exist a lot of other speakers with higher sensitivity that can perhaps be driven far better by the Leben. Please clear my confusion and report the results of actual hearing when you receive this combo. Or have you received them already?
To start, I'll throw in two extreme suggestions (extreme from price points). How about Viren's Amities? You have listened to them, I think. Have you given a thought to that? On the other hand, can your friend extend the budget to consider the Emerald Physics CS3?
As a third suggestion, I would put forth Audire. Have you been in touch with them? Do they have anything appropriate? Gobble and Moktan in our forum own Audire Callisto single driver speakers. May be they would know about other Audire speakers in the range your friend is looking in.
In light of what unleash has said about Harbeths, let me just say I did not mention them just on reading reviews on the net. I am long enough in this passion to know that at times(or is it most times?
) professionsal reviews can be biased or written in a particular way to favor a product or a combination. I tend to depend more on actual users' impressions, and if the actual user is experienced, there is nothing like it, even though everybody has a bias. In principle I fully agree with unleash's concern regarding the sensitivity. It is true that none of the Harbeths have a high sensitivity, and some are rather lowish. However, if you take a look at the Harbeth users' forum, you would find interesting information there about these speakers (like the SHL5 and the compact es-2 having average sensitivities)) being driven by a lot of low powered amps very happily and in particular by tube amps (like Lebens). In fact there exists a thread where the designer and the owner of the Harbeth speakers himself is discouraging use of high powered amps with his speakers.
Just google Leben cs300 +Harbeth and you would come to know about many happy users of this combo. But any way, unless your friend extends the budget even the cheaper pair (current version is the compact es-3's) would be outside consideration.
On the other hand, Leben CS300 and 300X/XS are such amps (according to reports by actual users and reviewers) that despite their lower wattage they can drive usual speakers well quite unlike usual SET amps.
I will quote part of my own post #392 from my amp thread in the following:
[\QUOTE]
Here goes an incomplete list (because there are actually more) of not-too-efficient speakers as reported on the net (most cases I have also included the source on the net) that have been driven very well by the Leben CS300 (12 wpc) / CS300X (15 wpc) / CS300XS (15 wpc):
1) Dynaudio Contour 1.1 (86 db, 4 Ohm)
(in the Czeck review
www.hifinazory.cz:forum:viewtopic.php?f=10&t=866)
2) Harbeth Compact 7e-2 (86db)
To quote:
"
I'm not sure i'd call myself an audiophile, i only have mid priced stuff. I use a Leben 12-watt vacuum tube amp (cs-300), and an Arcam cd-33t with my Harbeth compact 7-es2's. I sit close - about 1 and a half metres away. I can't turn the amp up past 11 o clock, or the police will visit (This is Japan!) . Anyway, It sounds superb. I previously had an older (Quad), more powerful amp, but it sounds feeble in comparison. I imagine this power would be quite sufficient in any small/mid sized room, though i guess things might start to deteriorate at a certain point in a largish room. I can't imagine why much more power would be needed in a relatively small space. The whole set up sounds very convincing and bold to me. I've got repetitive strain injury in my feet from too much tapping." by member "holden" in thread "How little power do I need for my Harbeths?" in a Harbeth user forum.
3) Harbeth Super HL5 (86 db, 8 Ohm)
4) Totem Arro (87 db, 4 Ohm)
(Look at the post by "Jasonics" in
ClubSNAP Audiophiles thread - ClubSNAP Photography Forums )
(See also
Singapore International Sound & Sight Exhibition 2007 Electronic Show Report and Audiophile Coverage by Enjoy the Music.com )
5) Sonus Faber EA-2 (86 db)
(see post #8 at
Enough Valve power 10w into 86db Speakers - 2 Channel Debate - All things HiFI and AV - HiFi WigWam - HiFi Forum)
6) DIY Breitbander (85 db) in the LP magazine review
7) Harpia Acoustics (84 db) (in the High Fidelity Polish review)
8) Roksan FR5 (87db, 4 Ohm)
9) Proac Tablette (86 db, 8 Ohms) (in Italian videohifi.com) (for the 300X version)
10) Quad ESL 988 (86 db, 8 Ohm) (used in the swedish review of bildochljud.se)
11) Quad ESL 989 (86 db, 8 Ohm)
(Swedish forum
Leben CS300 - Euphonia Audioforum )
12) Totem Model 1 Signature (87 db, 4 Ohm) (found in the same euphonia-audioforum above)
13) Totem Dreamcatcher (87.5 db, 4 Ohm)
(see posts 22 - 26 in
Leben cs300 vs Audio Note oto se? - Page 2 - pink fish media )
14) Sonus Faber Guarneri (86.5 db. 6 Ohm)
(see post #53 in
Best Valve Amp Between 2000 - 5000? - Page 4 - pink fish media)
15) ProAc Response 1 SC (86 db, 8 Ohm)
(see post#24 in
Best Valve Amp Between 2000 - 5000? - Page 2 - pink fish media)
16) Devore Gibbon 3S (86 db,8 Ohm)
(see
Devore Fidelity Gibbon 3s Loudspeaker Review at On Speakers)
17) Spendor S5e (87db, 8 Ohm, Min 4.4 Ohm)
(see
6moons.com - letters & feedback)
[\QUOTE]
However, at the end, I must warn you. I did the above research to convince myself that the Leben would drive my Cantons well. Use this information as you like. Of course there is no denying that more sensitivity is always better, but sensitivity is not the last word on the speaker-amp matching. Impedance vs. frequency curve of the speakers especially at lower frequencies is also a very important parameter. Of course I knew that my Cantons had very high sensitivity, but I could not locate any Impedance curve for these old speakers, and hence I wanted to be as cautious as I could and informed myself the best possible way. For example, if my Cantons had a sudden dip of impedance at a certain frequency, it sure would create problems, depsite it being very sensitive.
Most of the above have been discussed in my amp thread, but I have reproduced it here again, because the length of that thread makes it difficult for anybody to find the relevant stuff.
Regards.
