The inefficiency issue... | Magnepan LRS+ & Bryston 3B Cubed Power Amp Review 

My LRS+ speakers arrived 2 weeks ago. I power them with a Starke Sound Fiera4 (This class D amp suppliers 260 W RMS at 4 Ω (1% THD，per channel) but allows for bridged operation of the 4 CH into 2CH at 500w/ch. This is a match made in heaven, providing open, strain-free reproduction at levels louder than I ever want to listen at. But here’s the kicker. I’ve been experimenting with Dirac room correction as, in my room, the LRS+ has way too much energy in the 70-90 hz range and way too little energy in the 120-150 hz range. I’m early in the experimenting stage but, so far, I’m very pleased with the results.

Tom, Thanks for another great LRS+ review! FWIW, obtained a "full optioned" Starkrimson Stereo Ultra amp in July to drive my 86db AA Sierra-2EX stand monitors. The Additional power (+6db more headroom than prior amp), control, transients, dynamics and soundstage 3D clarity presentation is just Stunningly Amazing!! Now, I-Am-There in the live recorded audience venue, with performers and musicians precisely in their proper space (beyond back of the monitor baffles) and with realistic air, size and dimensions of each! Most listening sessions elicit Ho..Sh.. moments, as it now becomes jaw dropping LIVE!! 😊

If you can afford a Bryston amp go for it but most people can't afford it and that is where the used market comes in. The big question here is can the amp supply enough current something total watts won't tell you ,now If the output power doubles when you half the impedance it most likely will. I am using a used Sunfire Ultimate Receiver II (with it's unique tracking down converter power supply ) it puts out 200W x 7 into 8 ohms but more importantly it puts out 400W into 4 ohms in 2 channel mode and can deliver 800W into 2 ohms on a time limited basis. It makes the LRS's sound fantastic for a fraction of the cost of a new amp. Watch Ron at New record day review the .7's to see it takes muscle not just money to drive them.

It's true but worth mentioning a warning to new Magnepan owners. I just bought a vintage pair of MG 2.5R, hooked them to my 350w Rotel amp, and promptly blew the tweeter fuses in them, lol.. Maggies, especially older Maggies, are power hungry and just don't play as loud as large/equivalent size traditional speakers. So it's a lot easier to max out the fuses than you think when you're not familiar with how they play.

LRS with Bryston 3Bsst here. 13x19x 7.5ft room. 2 REL subs. Very satisfied. Not attempting concert volume though. Timbre more important to me. Enjoyed this presentation, thank you! 🎵🎶🙂🎶🎵

I use an old modded 100 watt Quad 405-2, and it goes plenty loud for my LRSs. Part of the challenge is the impedance swings of this speaker, & as the Quad was designed for use with electrostats so has headroom for those low Ohm dips

Great points.May I suggest a future video of what other amps (of all classes and price points) which have that synergistic sound with the LRS+.

I forgot to mention that the Stark Sound Fiera4 is priced at $1499 MSRP so, IMO, an incredible bargain.

I am using used Rotel RB-980 BX amplifier with my Magnepan 1.6 QRs. I have no problem driving them in a room 18X 20X 7.5 feet. Volume knob on my Preamp (Adcom 750P) never has to go above 9 O' clock to 10 O' clock position. Lately I am thinking of upgrading to monoblocks.

Would an Audio Research D125 power amp with 8 6550's fit?

Your comments about the LRS+ and the necessary power that one would need to drive them properly is appreciated. I saw an online review which took the LRS+ apart and they noted that in stock form the speaker's tweeter is crossed over at a very low point making it possible to overdrive the tweeter with little power. Your review seems to suggest that that speaker comes alive with lots of wattage. I am trying to reconcile the two positions with respect to power ratings. Any thoughts?

What are those boxes in the corners?

FWIW Tom: JA at stereophile estimated the efficiency of the LRS at 80db! Since they radiate in both directions, they're hard to equate with boxes. At 1 metre you're not measuring the full output of the large panel anyway. (The inverse square rule seems to be strangely circumvented by their design also.) I run mine with GiK abfusors at 45° across the corners behind them with bass trap behind that (Diffuses the back wave nicely). REL subs on the space below. Visiting friends marvel that the music just IS - not seeming to emanate from the panels at all, with a visceral substance to the sound. I'm very grateful to Magnepan for these two slices of Magic at such a reasonable price! I've found my last speakers 🎵🎶😊🎶🎵

I love my 1.7i Maggies! And they love my room based on how they sound when you get them going! But the room is a major and unfixable problem! Behind them is a 17' high wall with a partial opening to a balcony to the right. The ceiling slopes diagonally to a corner about 38' away. The wall to the left of them is only 8', so open above it to the ceiling. And there are openings to walk and pass stuff through. So it is more of a barrier in a room roughly 40' x 35'. Lots of angles and openings, stairs,.... They overheat my ADCOM GFA555 if I really push them. But the available space really lets them sing! The depth and width of sound stage. And interestingly how they energize the room which you hear as you walk around it. But I hope to move them down to a listening room after it is done.

I have Magneplanar MG-IIIIa speakers and drive them with an original Adcom GFA-535 amp. It outputs a "whopping" 100 watts/channel into 4 ohms. I have read that this amp does have a significant amount of headroom. I have no problem driving my Maggies to levels so loud I cannot stand to be in the room - what I would call "deafening" volume - before clipping indicators on the amp come on. The listening room is approximately 14' wide by 22' long.

Hi , I have the LRS + on order. I presently own PS audio Stellar Gain Cell DAC and 2 M700 monoblocks putting out 700 watts per channel at 4 ohms. Also damping factor of > 1100 . Should this be a good match for the LRS’ + ‘s ?? Thanks for you input!

Just rewatched this, a good tube preamp and a class D crown amp works, then latter upgrade . Yes the mags need 200-600. Open baffle subs can be fun.

I have the Rotel 1592 MK2 driving 1.7i. Before that I had the Sound Artist SA200ia driving them. I obviously like my Rotel better, but I honestly think you would be shocked by what the Sound Artist got you for around $400.

I just bought 1979 MG IIA ' s (1994 refurb) and am running them with a NAD C700... I would recommend more power and perhaps A or AB amp. Surprisingly, the C700 does sound great with them, it just "needs a bit more". BTW, loving the maggie's. I also appreciated your point about a $5000 amp with $1000 speakers. A sales person and I were just talking about that. Your speakers are only as good as your source...DAC, amp, preamp... Like in business, bad data in = bad data out. Bad sound in = bad sound out. If you are on a budget, which most are, put money into the source. Someone could say, well....the best amp in the world will also not make a crappy speaker sound good...that is true. But... a bad amp will make nearly all speakers sound bad. So statistically-speaking, it's best to put the money into the amp.

I'm a little confused about the new Magnepan subwoofer. Do you know if it's meant to be a standalone full range speaker or is it meant to be used in conjunction with something like the LRS+, which I've heard can be a bit weak on bass? I know you can used them standalone. I've seen all the recent videos of people blown away when they find out the LRS's amp was turned off while music was played in a demo of the subwoofers.

A pedantic note on the dB calculation, "double the power for 3 dB" is a (pretty good) approximation, if you want to be exact you should count 10x power for 10 dB. FWIW, double is around 3.0103 dB :)

High current amps into 4 ohms?

From my experimentation and others it seems that watts are not really the thing you need. You need some of course but I think Gain is more important. And noise reduction just after that. A preamp with 12 or 20 db of gain makes a world of difference. Lets say your amp has 26 or 29db's of gain and you put 12 to 20 more db's on top of that you'll hear it for sure! Second, noise, because most of us don't really realize how much noise we're asking our amps to push instead of sound. I realized at some point going up the latter and reaching 800 watts in 4 ohms that i was still unimpressed. Why? The gain was the same on my amps and the style of cables i was using. There was a difference but not enough for the wattage. I realized that noise getting in, masquarades as "highs" or "air". When you play with cables and now i build my own, you realise that a lot of "air=noise" gets in ,especially at both ends of the cables. When you try full aluminium casings (but carbon/metal are better to my ear) on both ends of an AC cable and you get at least 2 of these in your system you'll notice that your entire system sounds way stronger. Why? Because the proportions of sound versus noise = air your pushing has changed and the mids and midbass are way more prominent now. The effect is so obvious that if you accumulate more of these cables you can easily go overboard and feel like there is not enough air in the sound. At that point i change the heads with silver plated copper to get some air back wihhout introducing noise. But my point is that you can dramatically change your impression of strength from your amp by simply changing the AC cables that are in the system and thus getting way more from your amp than you thought it could deliver. I call it the Hegel/Naim effect. The main reason they sound so much stronger is because of their capacity to block out noise and push sound instead of air. Gain plays a part of course but if you dont have the money like me, cables are the way to go and additional gain from a preamp. A good 12db or 20db of gain from a preamp makes a lot of difference in the strength that you have at the other end to drive your Magnapans. I went from 300 watts to 600 to 800 watts into 4 ohms with 1340watts peak and was still not impressed because the amps we're all the same db's of gain and i was pushing noise ,that i couldn't hear, but was evidently there... Now just with cables , i can make low wattage amps sound way stronger. They're not stronger they are just pushing the right proportion of sound and air thats all. That's my experience anyway.

I have recently purchased the LRS + and I bought a peachtree gan 400 to power it. Both are still in the break-in period. I am also waiting for the magneriser to be shipped.

there is an extensive write-up of the LRS+ in the Oct 22 issue (no. 331)

Had many maggies and did enjoy them but the dynamics were so compressed I had to move on. I still run AMT and ribbons but have moved more into horns. Horns allow me many amplifier options inefficient designs are limiting and may save money on purchase but make you pay much for amplification and electricity. I can run 1000 watts or just 2 on many of my horn systems I can pick SET PP Class A -D OTL whatever I want.

Magnepans's have no enclosure so no sound of their own. I bought old but rebuild 0,5's for only 250 euro/dollar. My 60 Watt tube mono blocks were not able to handle them. So I bought an Ayre V6 2x300 Watt for 1900 euro and they sound great. This combi will be hard to beat for the money. Now I wonder will a 1.6 or 1.7 sound better in my small room, 10 x 15 feet? Any suggestions?

Always better to have HEADROOM, especially for Mahler!! In my dedicated space (18x24x8), I have a Parasound A-21 driving a pair of Martin Logan Classic 9's (90 DB efficient) from their Masterpiece series. Sitting 20' from the speakers at the listening post, the suggested 400w. pc. by Martin Logan, for orchestral recordings, it's all the dynamics and sound pressure levels one could ever need. Ear damage can and WILL occur.😵‍💫 Needless to say, I have never topped that amp out!

My $600 Polk L100s love my Levinson 5302 power amp.

Schiit Vidar 2? or even 2 of them 400w less then 2k

My Mark Levinson is rated 100 wpc 8 ohms, 200 wpc at 4 ohms, 400 wpc at 2 ohms. It makes my LRS to 1.6R (modded) sing with glory.

Its not about raw power...It's about the amplifiers current capability. I have LRS and I run them with 12wch tube amplifier. They play plenty loud in my 12 X 24 X8 heavily damped room....My 50wch Pass Lab First Watt F5v2 really makes them come alive. You don't need 500-1000 watts to get LRS to perform......

Kudos to TAS for all the interviews and product discussion videos - coincident with Fremer’s addition, you guys have been flooding the airwaves (Alon Wolf, Mark Spitz, Nagra…) - but…could “Tom” at least introduce himself at the beginning - I’ve been an audiophile for 50 years, read everything that comes out but find it off-putting when on multiple videos, someone just starts talking - rather than listening I spent most of the time wondering “who is this guy?”

That math is at 1 meter away too. There's an additional multiplier for every 1 meter back to the listening position. Ouch! 🔈🔉🔊

I run Outlaw M2200 Monoblocks on my Magnepan MMGs.

I have often felt the 60% of your audio budget should go towards speakers as an outdated approach. I find that one should first find the speaker that suits their taste and budget first. Then allocate towards the amp that has best synergy towards it. In short, the amp and speaker should be considered as a whole not individual pieces at a given price point.

My Marantz PM 8006 is 8 / 4 Ohm 70 W / 100. Want to get a pair of the LRS+ but I've been told it's probably not a good match.

Has anyone up there in AS heard of or tried the hi-fi player app, 'USB Pro' . . . a great sounding, downloadable digital player App, for PC or any streamer. Wait for it!

Will the Bryston 2.5 cubed be enough power for the LRS+ ???? HELLO- ANYONE?

I don't believe an LRS+ could EVER produce 115db. And I don't believe you could hear an instrument playing at 30db in your room as you suggest - 30db is like a whisper.

I’ve read two downfalls about the speakers. One is they don’t sounds great with an Adcom GFA 555, and two, they don’t handle Led Zeppelin well

It's not inefficiency that stopped me from buying Magnepan. I have sufficient power, but I found in auditions that the speakers really do not come alive unless they are played loud (>85dB). Even with plenty of power/current, they sound flat at listening levels that I find comfortable (65-75dB). I'll call this insensitivity. At 85-90dB, they make magic that is incomparable, but that is not the way I listen to music on a regular basis.

If you need a high current/high power amp to drive the LRS+, then why does a 20-25 First Watt Nelson Pass amp drive those speakers just fine?

I use a Crown 1502 XLS amp rated at 525W into 4 ohms and my 1.7s sing. It annoys my audiophile friends that I use a Crown, but it works and works well. My room is 19x17x8.

@14:39 not really true anymore in my opinion. Class D amplification has really come a long way. Crown makes some great stuff around the $500 range that measure extremely well with tremendous power. They aren’t much to look at but they’ll be objectively better then many amps that cost a lot more.

Yes, min would be Quality 150 W 300 would be better

The Magnepan website states that to properly drive their speakers, the amplifier should come close to doubling the watts going from 8ohm to 4ohm. No Bryston amplifier comes close to that. Equating higher price with higher quality came become self fulfilling.

Watch the video at 1.5x speed.

Sadly the crossovers in the mags are not made with great parts,

What is this guy taking about? Anyone with any experience in this area always talk about current vs power. It is all about current with Maggies. Plenty reasonable price equipment can work well.

aaaaaahhhh

Respectfully, sir, not as helpful as I'd hoped. 17 mins into this video I'm ready to throw myself under a train if I hear once more how much I need to spend on amplification -- without any actual amplifiers recommended (not even the Bryston is discussed).

This is was an interesting video. But this person takes forever to make key points.