Magnepan LRS too much for BHK250?

Yikes, that is not a good look if a factory verified BHK cannot handle the baby Maggies, whatever the reason.

My only experience with LRS was at dealer auditioning the Rega Elex-R vs bel canto cs5i integrated amps, msrp of each under $2k. Neither had any trouble with the LRS at normal listening volumes over a one hour listening session. To be honest, had one of these much less expensive amps been unable to drive the Maggies I would have been disappointed.

On a side note, I wasn’t impressed with the LRS. Inexpensive, sure. But there are better speakers to be had for under a grand in my opinion. Even at $600, give me Kef Q150 (which I own as backup in third system) all day long. By contrast I was very impressed with a 3.7i audition (bel canto black electronics) I just could never get past the visual aesthetic (no way I could own in living room environment and remain married) but they sounded great.

I don’t follow LRS threads across the web but for those who do, are there widespread reports of other company’s amps being insufficient to drive LRS? Is this a big issue with these speakers for many amps?

I was responding to another poster who was looking into the .7

LRS appears to be power-hungry and particularly demanding if you need to play them at REALLY HIGH volume.

It just continues to boggle my mind, every time I see this thread bumped to the top.

I don’t have the LRS but I do have .7’s (both show the same 86dB sensitivity), and I’m running them from a Parasound Hint6 integrated. 270W into 4ohms. For current, it’s 45 amps peak per channel. It’s flawless.

With as much power I would assume the BHK250 has, I can’t believe that it can’t properly drive the LRS. 500W into 4ohms, right? How much current? Is that the secret sauce?

With a tested sensitivity of 80dB, and an impedance of 2.8 ohms between 400 and 600Hz, these speakers present a very difficult load, especially when played loud as described by the OP.

It sounds like this is a good reason to start with the .7 and skip the LRS.
I drove .7’s to occasional “party” levels very well with just 30 watts.
Everything seemed to play nice together, no drama.

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I definitely believe the sensitivity of the LRS has to be much lower than 86db. They do sound great and perform flawlessly with the Stellar M1200’s…

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well, I don’t doubt that the speakers test less efficient, but it’s amazing the BHK250 can’t handle them. I mean, it’s 500 WATTS PER CHANNEL!

I don’t play at wall-of-sound levels, and my room isn’t enormous, so I might have a different set of criteria.

Given there are a number of amps identified n this thread which have an issue driving these speakers, plus more reports (quick Google search), it appears driving these speakers loud can be a big problem.

My guess is when provided with sufficient current to drive the speakers loud they behave as a short/high resistance - signalling the driving amp to turn itself off in protest. Driven moderately the speakers are apparently not a problem.

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To the contrary, on a quick read of thread again the only amps I see people having issues with are a $700 Schiit and Emotiva.

That’s probably not the competition PSA wants for BHK.

That’s why I asked about other amps. Now I will say again why in the world someone would pair LRS with a $7.5k amp escapes me (no offense intended OP, it’s just a really odd pairing based on the order of magnitude price difference), but that doesn’t eliminate the issue OP having.

But we are talking about a signature level amp priced at $7.5k and spec’d stable at 2 ohm transients, so yeah it does seem unexpected I’d think.

Yes, plus a Goggle search as I mentioned in the same post.

And in each case the user makes a point of indicating they are playing the speakers loud. Thus, as I stated, I suspect there is something about the speakers when pushed hard which causes the problem.

There are many reports of using modestly powered amps with success - as in the Stereophile review - at modest levels.

Amps do not respond well to loads which act as a short, regardless of the price of the amp.

Of course, there could be a design deficiency in the BHK250. But given other amps have the same problem when driving these speakers loud I suspect the speaker.

The answer is… WHY NOT???

Probably that was to me. I hear ya. I always cross test everything I have too (sitting here A/B’ing two of my speakers as I type) and would have tried it myself. I shouldn’t have questioned the pairing.
Cheers!

I should add, that when purchasing my LRS’s I had the unusual opportunity of buying them from Wendle at Magnepan, the big man himself (he just happened to answer the phone). He quizzed me a bit on my amps and seemed to think the Emotiva XPA’s would be more than capable of driving them. They were not.
I run Wharfedale EVO’s now with zero issues (and much nicer sound) and I ran my Martin Logan 35XT’s with the Emo’s with zero problems. So yeah, LRS’s seem tough to drive…

For what it’s worth New Record Day on YouTube has a video where Ron shared a lot of detail about his troubles finding the right amp to drive the .7’s properly.

The LRS was meant to be a speaker to give people a taste of the Magnepan sound at a low cost and nothing else. It required them to take short cuts to get it in at the price target. The main shortcut was it’s less than optimal impedance profile when driven hard in a larger than optimal environment. So if you are having problems with the LRS then chances are you are driving it to hard in the wrong room. No fault of the speaker or the amp. The fault lies with the owner who is expecting something more than what the speaker was designed for.

From their website after they mentioned the previous SMG speakers of the same size could be driven by and were designed for also cheap receivers:

„The LRS was designed using high-end electronics and mono blocks. The LRS will perform nicely with a receiver, but it was intentionally designed to extract the most from high-end amplifiers and electronics. The LRS expects more from a properly designed high-current amplifier. That is a radical departure from most entry-level loudspeakers. If you put your expensive high-end amplifier on the LRS, you will hear the difference.„

I am happy with the speakers even with all its “difficult” features. Like I’ve said before, I am now driving them with Stellar M1200’s who do an amazing job and have no problem with them. My room is not large and does not have anything to do with the problem I was having with tht BHK250…

I don’t think that’s fair to LRS, because there are plenty of amps that don’t buckle and allow the LRS to reach full potential.

Either an amplifier is up to it or not.

LRS isn’t the only speaker with a difficult load profile. At end of day each speaker is just a load profile that any given amplifier is either capable or incapable of driving across the speaker’s performance spectrum

Just out of curiosity mdiaz, have you measured your average and peak db level c weighted at your listening position? I’d like to know what you listening loudness preference is. Thanks!