• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Magnepan .7s Tube Amp? SS?

Reel1

New Member
Joined
Jan 14, 2020
Messages
4
Likes
0
Good afternoon everybody! New member here and absolutely love the amount of technical info found on this forum. Have been trying to learn more about the different designs and options. Have read a few of the Magnepan amp threads but still had some questions.

I bought a pair of Magnepan .7s a few months ago and was wondering if I would be better off with a Tube amp or SS design. I was originally going to buy the Schiit Vidar, but then found a good deal on a PrimaLuna Dialogue Premium. Obviously the Vidar is not as expensive but if the Primaluna will be that much better, I rather spend the money upfront from the beginning.

I have a turntable and phono stage, and plan on buying a DAC later on so don't necessarily need integrated. Any suggestions on options/amps appreciated, Thank you!
 
Last edited:

dkinric

Addicted to Fun and Learning
Joined
Nov 21, 2018
Messages
666
Likes
1,446
Location
Virginia, USA
Reel1, welcome to ASR!
Congrats on the Maggies, I would love to hear them. My understanding is they thrive with lots of power and an amp that can handle a low impedance load. You likely won't find as much love for tube based amplification on this site as others as they do not provide nearly as good measured performance as good solid state amps. Some may prefer and enjoy tube amps, but realize it is a personal preference and not objectively better - distortion is usually very high compared to solid state. Smilar to vinyl - you may like it for various reasons, and that's cool - but realize it's not objectively better than excellently designed digital sources and solid state amps. The cool thing is, these don't have to be expensive. One of the biggest takeaways from here is that there is not a big correlation between price and actual performance.

Some of the best measured amps we have seen are the Hypex and Purifi based class D amps. These put out a very clean, powerful, low distortion signal with extremely quiet background - would sound amazing on the Magnepans. You say you don't necessarily need an Integrated, but having a turntable, phono amp and DAC is not really relevant to that - a basic integrated combines preamp/volume with amplification - whether they are included with the integrated or not is a different matter.

Also, are you using any kind of sub(s) with the Magnepans? IMHO, the several grand spent on a Prima Luna tube amp would be better spent on a pair of Hypex or Purifi monoblocks and a powered sub(s). Since you asked :)

Suggest you stick around here and read up a bit with an open mind and you may end up with a whole different perspective on the audio industry.
 

raindance

Major Contributor
Joined
Sep 25, 2019
Messages
1,037
Likes
968
A tube amp of more than 100 watts per channel works reasonably - I've tried it. However, it'll leave you wanting more. You lose some "snap" and you lose some treble extension, which is a bit already limited on the .7. Also bass gets a bit looser. Audiophool tube amps that use low levels of feedback also generate copious amounts of audible distortion at anything above 5 watts or so, so the power rating comes with caveats.

Solid state amps capable of running 4 ohms work best. Typically we suggest amps that can double their 8 ohm output power into 4 ohms. And don't waste money on a tube preamp. They don't typically sound tubey.
 

thanhh

Member
Joined
Sep 17, 2019
Messages
38
Likes
25
Hi,
I happen to have the MG12 QR (older version, similar size to the 0.7) driven by both tube and SS. This is my impression:
  • Primaluna prologue classic (KT88 - 40W): it can drive the Maggies reasonably loud, I had the volume pot at 2 o'clock position and get average 85Db seating 2.5m away from the speakers. The bass always suffers on this amp but amazing mid range. I use this amplifier mainly to listen to over-compressed, low dynamic range music. It makes these albums easier to listen to. It goes great with acoustic as well.
  • Quad Elite Power amp (75W @8Ohm): Bass and details slightly better than the Primaluna (on good records) but not by much.
  • Crown xls 2502: I was sceptical with this amp since it's cheap ,a "PA amp" with not so great measurements but it's been the main amp for the Maggies since I've got it. I tried to listen to high DR track with average Db of 100Db and the -10Db light on the amp only blinks occasionally and I haven't seen the clipped light ever blink yet. Everything just sounds better with this amp. So yes, I believe you need at least 400W @4Ohm to make those speakers sing.
I hope this help and my English makes sense to you :)
 
OP
R

Reel1

New Member
Joined
Jan 14, 2020
Messages
4
Likes
0
Wow! Thank you for those replies. Didn't think it would be that detailed. Im probably more enamored with the nostalgia of tubes/aesthetics, even though I have heard the PrimaLuna with the .7s and thought the combo sounded great (Mainly vocals/acoustics, volume wasn't too loud). Just like with the turntable.

If I'm better off with the solid state, then will go that route. I had read that Magnepan did not like Class D amplifiers. That it sounded grainy. Is this accurate?
 

Blumlein 88

Grand Contributor
Forum Donor
Joined
Feb 23, 2016
Messages
20,521
Likes
37,050
Wow! Thank you for those replies. Didn't think it would be that detailed. Im probably more enamored with the nostalgia of tubes/aesthetics, even though I have heard the PrimaLuna with the .7s and thought the combo sounded great (Mainly vocals/acoustics, volume wasn't too loud). Just like with the turntable.

If I'm better off with the solid state, then will go that route. I had read that Magnepan did not like Class D amplifiers. That it sounded grainy. Is this accurate?
I've used some earlier Maggies with tube amps. One of the keys is getting one set up for use with 4 ohm loads or close to it. I had an amp where you could pick combinations of the transformer secondaries suitable for 5.6 ohm loads and using a 4 ohm Maggie was close enough. It didn't sound like solid state, but it was not flabby in the low end or lacking in power.

I would say generally Maggies are better with good SS suitable for 4 ohms loads. More power is better, but you don't need tremendous amounts. I've not heard them much with class D amps, but I have for short periods of time, and they seem a very good match actually. Class D isn't inherently grainy. They'd sound very good with some of the Hypex class D or the Puri Fi amps Bruno Putzeys is behind.

OTOH, if you've heard them with PrimaLuna and liked it, well you have a successful audition. Don't let chasing an improvement cause you to skip over what you know works for you.
 

thanhh

Member
Joined
Sep 17, 2019
Messages
38
Likes
25
IMO, any amps that are measured good and got enough grunt to dive a certain speaker will sound the same (i.e. transparent)
To put in perspective regarding class D, the Maggies distributor here in Australia set up his system for Hifi show this year using class D and he recommends it for Maggies. If I have enough fund, I'll go with a Hypex or Purifi amp but atm, I'm more than happy with the Crown.
 
OP
R

Reel1

New Member
Joined
Jan 14, 2020
Messages
4
Likes
0
The thing is I haven't heard them with a good SS amp. At the dealer they also had the Primaluna for demo so don't have much to compare. I don't necessarily plan on listening at high volumes all the time, but felt like the dealer didn't play them as loud for some reason, maybe lack of power or their listening style.
 

raindance

Major Contributor
Joined
Sep 25, 2019
Messages
1,037
Likes
968
Depends on the class D amp. That's a generalization :) Check out some of the amps measured on this site. Probably a really good class AB (actually class H) amp choice is the Benchmark. I would not go for the Schiit Vidar, the "tuned by ear" sliding bias scheme doesn't make sense and I don't think it has enough power. I've tried the Crown XLS series and the .7's have great bass with that amp, but, in my opinion, rolled off, slightly thick sounding treble.

I use a large Parasound amp and it's well balanced.
 
Last edited:
OP
R

Reel1

New Member
Joined
Jan 14, 2020
Messages
4
Likes
0
So excited! Throwing out all the research I've done and starting again haha. I have seen the reviews by Amir and even though some things are over my head technical wise, I do appreciate the scientific approach taken to measure everything. So all things considered, if I have the choice, pick an A/B over D amp if they cost the same?
 

thanhh

Member
Joined
Sep 17, 2019
Messages
38
Likes
25
I think it's very hard to find anything class AB with the same cost as class D if they have similar specs. If you have the budget, you cannot go wrong with the Benchmark AHB mentioned above. Otherwise, have a look at those Hypex and Purifi class D amps that were measured by Amir
 

raindance

Major Contributor
Joined
Sep 25, 2019
Messages
1,037
Likes
968
However, I do wish we could measure this alleged grain. Perhaps @amirm could figure out a measurement for this :)
 

dkinric

Addicted to Fun and Learning
Joined
Nov 21, 2018
Messages
666
Likes
1,446
Location
Virginia, USA
Grain in a subjective term, likely caused by increased distortion at higher frequencies, which you can tell from the measurements.
We have come to a point where, using the $28,000 AP Analyzer, you can "see" via the measurements how an amp will perform/sound. The preferred approach (imho) is to invest in an excellent set of speakers where you like the sound, and feed them the cleanest signal you can with generous power as needed. And in most cases, add a sub. Or two.
With this, you are listening to the music/mix/mastering as intended, and not any added coloration of the components. It can be striking when this all comes together. That's my experience anyway.
 

DonH56

Master Contributor
Technical Expert
Forum Donor
Joined
Mar 15, 2016
Messages
7,834
Likes
16,496
Location
Monument, CO
I love tubes on Maggies and they are a relatively benign (if low) load. But they are insensitive as well as fairly low impedance so need some power, and panel modes can be an issue that low amplifier output impedance is better equipped to help. For those reasons I would choose SS. Class D amplifiers have come a long way and I strongly suspect "grain" is in the eyes (not ears) of the beholder. I am not running Maggies now but heard no grain in my MG-IIIa's driven by a class D amplifier (older Pioneer AVR) and plenty of Maggie owners use class D these days. When I last had mine set up I was using Emotiva amplifiers on them and they sounded OK to me. If I could not afford the Benchmark AHB2 I'd look at ATI, Emotiva, Outlaw etc. for conventional or (more likely) class D offerings from @March Audio, ATI, and others. There are many choices these days so the choice may come down to budget and looks more than audible differences.

YMMV - Don
 

Wes

Major Contributor
Forum Donor
Joined
Dec 5, 2019
Messages
3,843
Likes
3,788
the .7 is a small speaker so won't need a lot of current at 4 ohms - what is the room size and type of music you will play?

yes, the budget is most important - so tell us what it is?

I'd get a SS amp and not worry - if you want the kind of sound that tubes give you can use a tube pre-amp with your SS amp

Lots of good SS amps out there for you at very reasonable prices - it would take a really crummy amp to change the sound more than room setup will do....
 

DonH56

Master Contributor
Technical Expert
Forum Donor
Joined
Mar 15, 2016
Messages
7,834
Likes
16,496
Location
Monument, CO
the .7 is a small speaker so won't need a lot of current at 4 ohms - what is the room size and type of music you will play?

yes, the budget is most important - so tell us what it is?

I'd get a SS amp and not worry - if you want the kind of sound that tubes give you can use a tube pre-amp with your SS amp

Lots of good SS amps out there for you at very reasonable prices - it would take a really crummy amp to change the sound more than room setup will do....

As a small speaker it has less panel area and less bass output. How much power (current) it needs depends upon room size and speaker positioning, distance to MLP, and how loudly he likes it. Not sure I see a strong correlation between the size and amount of current needed... At the time I felt my larger MG-IIIa's needed less power than the MG-I's they replaced but that was a long time ago. But less bass means less power in general assuming he uses a sub to offload it. Magnepan rates all sizes the same sensitivity; I have questioned that, but they stand by it. I have not measured them in decades (save my own) so cannot verify. I'm probably wrong.

Agree with everything else!
 

MRC01

Major Contributor
Joined
Feb 5, 2019
Messages
3,422
Likes
4,029
Location
Pacific Northwest
My experience owning the 3.6R for 20 years is that you need more power than you think, and you want a solid state amp that is clean especially through the mids and treble. The numbers say they don't need that much power, but they've always sounded better on more powerful amps.

Does the .7 have the same ribbon tweeter that the 3.6R has? I find them to be more revealing than most headphones, not just a subjective impression but also in A/B/X testing subtle differences near the thresholds of my perception, they reveal differences I can't hear on good headphones (like HD580 or LCD-2F). That ribbon tweeter has very low distortion in the treble where our hearing is most sensitive to it, so if there is any audible discrepancy or shortcoming in the amp: frequency response deviations, distortion, whatever, you are likely to hear it. They've also always been a little less efficient than the Magnepan specs suggest.
 

DonH56

Master Contributor
Technical Expert
Forum Donor
Joined
Mar 15, 2016
Messages
7,834
Likes
16,496
Location
Monument, CO
My experience owning the 3.6R for 20 years is that you need more power than you think, and you want a solid state amp that is clean especially through the mids and treble. The numbers say they don't need that much power, but they've always sounded better on more powerful amps.

Does the .7 have the same ribbon tweeter that the 3.6R has? I find them to be more revealing than most headphones, not just a subjective impression but also in A/B/X testing subtle differences near the thresholds of my perception, they reveal differences I can't hear on good headphones (like HD580 or LCD-2F). That ribbon tweeter has very low distortion in the treble where our hearing is most sensitive to it, so if there is any audible discrepancy or shortcoming in the amp: frequency response deviations, distortion, whatever, you are likely to hear it. They've also always been a little less efficient than the Magnepan specs suggest.

Magnepan specs at 2.83 Vrms (not Watts) so they lose 3 dB on their sensitivity spec when you convert to dB/W/m. They are more directional than most conventional designs so have always claimed that makes up the difference. Maybe...

The ribbon tweeter is only on the 3.x, 20.x, and 30.x speakers, not the 1.7, .7, or LRS. The ribbon tweeter was to me a big step up from the 2.x series and below. It does drop the HF impedance to around 3 ohms or so (but still essentially resistive and little power is needed up there).
 

drbarney

New Member
Joined
Jan 16, 2021
Messages
3
Likes
3
An 833A SET with a Hammond 1642SE output transformer is ideal for 0.7s. I use DWMs with additional output taps from the Hammond transformer. On each DWM I connect the two 4 Ohm elements in series and in phase the DWN gets an 8 Ohm output and the 0.7 gets its 4 Ohm output. The transformer is built to carry 300 ma and the 833A draws 120 ma with 1000 Volts on the plate and a 600 Ohm output from a 245 driven headphone transformer connected between ground and the 833A grid running at zero grid bias the way you can with an 833A. It sounds better than the solid state amplifier the store used for me to audition the 0.7s.
1616071182962.png
1616071270336.png

The DC for the 833A cathode heater ia 10 Volts at10 Amps and the tungsten cathode will not tolerate any ripple in the pure DC it requires. You can use a car battery with a 0.3 Ohm dropping resistor to get started if you decide to build your own amp and I will send you instructions on how to build a power supply which uses a 4.5 Farad capacitor for the final filter if you want.
 
Top Bottom