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post #91 of 129 Old 03-13-2014, 08:05 PM
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Nelson sure looks the part-A modern day hippie version of Einstein.

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post #92 of 129 Old 03-14-2014, 06:27 AM
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Originally Posted by NagysAudio View Post

Hi Arnyk!!!!! Hi!!! It's been known since dinosaurs roamed the earth that field effect transistors sound like vacuum tubes. They even operate on the same principals and MOSFETs can replace tubes in most amplifiers with minimal circuit changes.

We used Hafler FET-based power amps for a lot of our DBT experiments in the late 80s and 90s. They were very good - sonically transparent. IOW they had no sound of their own. Therefore they could not possibly sound like anything, even most tubed amps. ABX tests comparing good FET-based amps with good bipolar amps are like watching paint dry - nothing to hear, nothing to report.

FET based class AB power amps are a trifle less efficient and a generally a little more expensive to build. Because of their rapid switching speed, FETs are enjoying a resurgence in class D switchmode power amps.
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post #93 of 129 Old 03-14-2014, 07:40 AM
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Back in the day-mid 90's or so I had a pr of Maggie MGIIIa bi-amped.

I used a pr of Classe DR-3 VHC-very high current-amplifiers with the optional bricks rolleyes.gif feed by a Klyne preamp-maybe a 5??
I thought the system produced a beautiful sound.

Later I moved up to a Apogee Divas with a Dax with the DR-3's.
Probably my favorite system I have ever owned.
Only trouble was the amps produced so much heat in my apartment you had to listen with the windows open in the winter and in your underwear in the summer:D

I know the current Classe amps don't sound anywhere close to the DR3's.
The Pass remind me of the DR-3's but are better in all aspects.


Not pictures of mine...




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post #94 of 129 Old 03-14-2014, 10:38 AM
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Originally Posted by trans_lux View Post

Back in the day-mid 90's or so I had a pr of Maggie MGIIIa bi-amped.

I used a pr of Classe DR-3 VHC-very high current-amplifiers with the optional bricks rolleyes.gif feed by a Klyne preamp-maybe a 5??
I thought the system produced a beautiful sound.

Later I moved up to a Apogee Divas with a Dax with the DR-3's.
Probably my favorite system I have ever owned.
Only trouble was the amps produced so much heat in my apartment you had to listen with the windows open in the winter and in your underwear in the summer:D

I know the current Classe amps don't sound anywhere close to the DR3's.
The Pass remind me of the DR-3's but are better in all aspects.


Not pictures of mine...





With those monster heat sinks they had to be Class A.

Hate to break anybody's bubble but we now know that Class A SS amps are really just Class AB amps that have been intentionally given way too much bias.
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post #95 of 129 Old 03-14-2014, 11:00 AM
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Quote:
Originally Posted by arnyk View Post

With those monster heat sinks they had to be Class A.


Hate to break anybody's bubble but we now know that Class A SS amps are really just Class AB amps that have been intentionally given way too much bias.

Yes they were Class-A all 45 watts. They would drive a 1 ohm load, which at the time was impressive.
Borrowed from another site-power supply capacitors, reaching 160,000 µF per channel.

Your certainly right. At the time I thought they produced a wonderful sound-especially with the Apogee Divas.
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post #96 of 129 Old 03-14-2014, 11:05 AM
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Quote:
Originally Posted by trans_lux View Post

Quote:
Originally Posted by arnyk View Post

With those monster heat sinks they had to be Class A.


Hate to break anybody's bubble but we now know that Class A SS amps are really just Class AB amps that have been intentionally given way too much bias.

Yes they were Class-A all 45 watts. They would drive a 1 ohm load, which at the time was impressive.
Borrowed from another site-power supply capacitors, reaching 160,000 µF per channel.

Your certainly right. At the time I thought they produced a wonderful sound-especially with the Apogee Divas.


Delivering 45 watts to a 1 ohm load requires the ability to supply about 6.7 amps to that load. Any amp that can deliver 180 watts to 4 ohms, of which there are great many, should be able to deliver 45 watts to 1 ohm as it can by definition supply 6.7 amps.
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post #97 of 129 Old 03-14-2014, 11:20 AM
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Quote:
Originally Posted by arnyk View Post

Delivering 45 watts to a 1 ohm load requires the ability to supply about 3.6 amps to that load. Any amp that can deliver 180 watts to 4 ohms, of which there are great many, should be able to do that as it can by definition supply 3.6 amps.
I'm not sure what it produced at 1 ohm all I know it was one of the very few amps at the time that could drive the 1 ohm Apogee Scintillas.
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post #98 of 129 Old 03-14-2014, 11:59 AM
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These would work with the MMG, I just need to sell my home :(

 

soulution 701 monoamplifier

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post #99 of 129 Old 03-14-2014, 12:21 PM
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Quote:
Originally Posted by trans_lux View Post

Quote:
Originally Posted by arnyk View Post

Delivering 45 watts to a 1 ohm load requires the ability to supply about 3.6 amps to that load. Any amp that can deliver 180 watts to 4 ohms, of which there are great many, should be able to do that as it can by definition supply 3.6 amps.
I'm not sure what it produced at 1 ohm all I know it was one of the very few amps at the time that could drive the 1 ohm Apogee Scintillas.

The point is that if you use an amp that is sufficiently oversized, driving low impedance loads is possible. In these days of good clean relatively inexpensive but very powerful amplifiers, specialized amps need not be used.
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post #100 of 129 Old 03-14-2014, 01:11 PM
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Quote:
Originally Posted by trans_lux View Post
 
Quote:
Originally Posted by arnyk View Post

Delivering 45 watts to a 1 ohm load requires the ability to supply about 3.6 amps to that load. Any amp that can deliver 180 watts to 4 ohms, of which there are great many, should be able to do that as it can by definition supply 3.6 amps.
I'm not sure what it produced at 1 ohm all I know it was one of the very few amps at the time that could drive the 1 ohm Apogee Scintillas.

 

I suspect that your statement needs qualification; very few amplifiers at the time could drive the 1 ohm Apogee Scintillas to maximum volume or sustained high volume.  Often, an amplifier will work fine, up to the point when one asks just a bit too much, and then smoke may come out of it.  This is probably why amplifier manufacturers often give minimum impedance recommendations, as failure may come without warning if one attempts to exceed the current capability of the amplifier.

 

If we look at the claims here for the Apogee Scintilla:

 

Max Sound Level

110db in a 40sqr meter room, approx. 350sqr ft

Sensitivity @ 3m

79dB

 

http://www.apogeespeakers.com/scintilla.htm

 

And if we assume (and I know the assumptions may not be right, but it is not stated precisely enough to know) that both are at 3 meters, and if the sensitivity is with 1 watt, it would take 1258.9 watts to get that 110dB (here is an easy calculator anyone can use).  If we instead decide that we want to listen at more sane volumes, we may find we only need 100 or 200 watts into 1 ohm.  An amplifier capable of 400 watts into 4 ohms could deliver (at least) 100 watts into 1 ohm (as this would be the same current demand, with a lower voltage demand).  That is a fairly powerful amplifier, and not that many non-professional amplifiers can deliver that much power today either.


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post #101 of 129 Old 03-14-2014, 01:35 PM
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Quote:
Originally Posted by Jack D Ripper View Post

Quote:
Originally Posted by trans_lux View Post

 
Quote:
Originally Posted by arnyk View Post

Delivering 45 watts to a 1 ohm load requires the ability to supply about 3.6 amps to that load. Any amp that can deliver 180 watts to 4 ohms, of which there are great many, should be able to do that as it can by definition supply 3.6 amps.
I'm not sure what it produced at 1 ohm all I know it was one of the very few amps at the time that could drive the 1 ohm Apogee Scintillas.

I suspect that your statement needs qualification; very few amplifiers at the time could drive the 1 ohm Apogee Scintillas to maximum volume or sustained high volume.  

Looks to me like someone is moving my cheese. I responded to a comment about 45 watt amplifiers, and now there is disparaging talk about "maximum volume", which is by the way exceedingly vague.

For the record here is a published impedance curve for the Scintillas:

http://www.lippaudio.org/MySystems/Scintilla/



And the sensitivity and power ratings are:

http://www.hifi-advice.com/Apogee-Acoustics-scintilla.html

Max Sound Level
110db in a 40 sqr meter room, approx. 350sqr ft

Sensitivity @ 3m
79dB

Another review says:

http://www.apogeespeakers.com/reviews/scintilla_hifichoice_1987.htm

"Sensitivity was rather low at 79dB/W, and the watt referred to here is a nominal 8 ohms reference"

That suggests that actual sensitivity is about 8 dB lower or 71 dB/W. Achieving 110 SPL at an approximate 18 foot listening distance in a 350 square foot room would take 39 dBW or just under 10,000 watts. If you pick the higher sensitivity number then power needs drop to a mere 1200 watts.

Apparently the guy with the 45 watt amp had to satisfy himself with peaks of from 87 to 96 dB depending on how you interpret the numbers.

Obviously, not a well designed speaker! I understand that they learned their lesson and never did that again!
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post #102 of 129 Old 03-14-2014, 02:25 PM
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I don't understand your comment about cheese.

 

What I am saying is that you are right that an amplifier that can drive a 4 ohm load can drive a 1 ohm load, with a quarter of the power at 1 ohms being the same amount of current as would be the case with 4 times the power at 4 ohms (e.g., 100 watts at 4 ohms will require the same current as 25 watts at 1 ohm, etc.).  If whatever the 4 ohm rating or measurement is, is the maximum current that the amplifier can deliver, then it will only be able to deliver 1/4 of that power into 1 ohm (because that would be the same current, which, by hypothesis, is the maximum current the amplifier can deliver).

 

The upshot is that many amplifiers can drive a 1 ohm speaker, but not with high power levels.  And so if high power levels are required for high volumes, then these amplifiers will be able to drive the speakers, but not to high volumes.  Consequently, in practice, they may be judged unsuitable, because they cannot deliver the volumes required.

 

The other point is that amplifiers that are used in such a way may be damaged if one attempts to have them deliver more current than they can safely handle, and this damage may come without prior warning. 

 

 

As an aside, the claimed information on these speakers that one finds online is limited and somewhat contradictory; here it is claimed that that 110dB @ 4 meters can be achieved with a 100 watt amplifier:

 

http://www.apogeespeakers.com/information/apogee_scintilla_info.htm


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post #103 of 129 Old 03-14-2014, 02:56 PM
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Driving a 1 Ohm load with a 10V amplitude using a 400W amplifier using a 65V power supply rail needs to be able to dissipate around 550W in the output stage.
It depends on the protection circuit. With dual slope protection the current limit depends on the output voltage.
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post #104 of 129 Old 03-14-2014, 03:04 PM
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This is from the new Apogee speaker site
Quote:
When released in the 1980’s, Apogee’s original Scintilla speaker struck both fear and joy into the heart of an audiophile, delivering beauty in music beyond the finest electrostatics, whilst bringing all but the most unbelievable amplifiers (Krell) to their knees! The joke goes – “Scintillas need amplifiers filled with smoke to drive them – when the smoke escapes they no longer work!”. At a 1 ohm nominal load I am personally amazed that the Scintilla ever saw production, but ask any Scintilla owner today and they will tell you they are very glad they did!


Quote:
Apparently the guy with the 45 watt amp had to satisfy himself with peaks of from 87 to 96 dB depending on how you interpret the numbers.
Obviously, not a well designed speaker! I understand that they learned their lesson and never did that again!

To be clear I had Divas which yes were easier to drive but still was a demanding load.
All I know is that with the DAX-active x-over- and a pr. of the DR-3-mind you the very high current versions- the sound as I remember was magnificent.
Though it's probably like a lot of things in life that you once coveted from your youth.
The 1st time I had the chance to drive a Lamborghini Countach was about the most disappointing event I can recall.
Something's are best left as just memories.
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post #105 of 129 Old 03-14-2014, 03:30 PM
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The bass panels had the magnets on one side only. This caused second harmonic distortion may have sounded euphonic at the time.
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post #106 of 129 Old 03-14-2014, 04:26 PM
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Quote:
Originally Posted by Frank Derks View Post

The bass panels had the magnets on one side only. This caused second harmonic distortion may have sounded euphonic at the time.

 

There are many large panel speakers that have magnets on one side only.  I believe most (but not all) Magnepan speakers have been made that way (for the large bass panels, not the tweeters).  Are you saying that they all have high levels of second order harmonic distortion when there are magnets on only one side?

 

In the case of the Apogee Scintilla, the woofer is crossed over at about 500 Hz, so this would be an issue for frequencies below that point.

 

 

As an aside, I have never even seen an Apogee Scintilla, much less heard one.  But I would like to out of curiosity, and would like to see some careful measurements of it as well.


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post #107 of 129 Old 03-14-2014, 04:49 PM
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Yes, if the surface move forward the magnetic field get lower and when moving backwards the field get stronger. This change in force is not linear causing the excursion to be asymmetric.

This is a basic design flaw.
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post #108 of 129 Old 03-16-2014, 12:57 PM
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What kinds of distortion are added by having extra mass to a driver, as with a conventional cone being pushed by a voice coil?


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post #109 of 129 Old 03-16-2014, 02:38 PM
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Depends on the design.
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post #110 of 129 Old 03-16-2014, 03:43 PM
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Quote:
Originally Posted by Jack D Ripper View Post

What kinds of distortion are added by having extra mass to a driver, as with a conventional cone being pushed by a voice coil?

Nothing of significance.

However, added mass can have dramatic effects on frequency response and efficiency.

Mass is often added to subwoofer driver, either in the basic construction or added-on, to extend bass response at the expense of efficiency.
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post #111 of 129 Old 03-16-2014, 05:37 PM
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From looking at this review of the Magnepan MG1.7, what has been said about second order harmonic distortion seems right:

 

http://www.hometheaterhifi.com/floor-standing-speakers/floor-standing-speakers-reviews/magnepan-magneplanar-mg-17-flat-panel-quasi-ribbon-full-range-speakers/all-pages.html

 

Not enough frequencies are tested to make me happy, but the one relevant to the bass panel has a high level of second order harmonic distortion, as stated for panels driven from one side only.  The upper frequencies seem fine, which, of course, are driven in both directions equally.

 

The question, though, is why such speakers seem to have great clarity and low distortion, from a subjective standpoint, and sound better to many of us than conventional speakers.  The MG 1.7 evidently does have low distortion, at least for some frequencies dealt with by the non-woofer drivers, but often such panel speakers, subjectively, seem to be low distortion generally.  I listen to Apogee Stage speakers, and they, subjectively, seem clearer and less distorted than any conventional speaker I have ever heard.  Why would this be the case?


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post #112 of 129 Old 03-17-2014, 06:20 AM
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Quote:
Originally Posted by Jack D Ripper View Post

From looking at this review of the Magnepan MG1.7, what has been said about second order harmonic distortion seems right:

http://www.hometheaterhifi.com/floor-standing-speakers/floor-standing-speakers-reviews/magnepan-magneplanar-mg-17-flat-panel-quasi-ribbon-full-range-speakers/all-pages.html

Not enough frequencies are tested to make me happy, but the one relevant to the bass panel has a high level of second order harmonic distortion, as stated for panels driven from one side only.  The upper frequencies seem fine, which, of course, are driven in both directions equally.

I didn't see where the review covered sure and potential reasons why there may be so much nonlinear distortion at low frequencies.

(1) The bipolar open back nature of the speakers causes a dramatic loss of efficiency at low frequencies. Speakers generally develop a front wave and a back wave that are often exactly 180 degrees out of phase. If they mix they cancel. Low frequencies being non directional will mix unless they are kept separate. The purpose of the typical speaker box is to keep these waves separated.

(2) Speakers are like amplifiers in that they may be single ended or push-pull. In a speaker push pull means that the source of force on the cone has a big dose of symmetry. The magnetic motors in a speaker of the typical kind may or may not have this symmetry. It depends primarily on the care taken the design of the magnet assembly and the voice coil. Subwoofers with pair(s) of low frequency drivers mounted intimately back-to-back or front-front and driven out of phase pick up an extra measure of this kind of symmetry.

Symmetry usually leads to a total or partial cancellation of even order nonlinear distortion. A speaker that generates large amounts of even order distortion is revealing its asymmetrical operation.
Quote:
The question, though, is why such speakers seem to have great clarity and low distortion, from a subjective standpoint, and sound better to many of us than conventional speakers.  The MG 1.7 evidently does have low distortion, at least for some frequencies dealt with by the non-woofer drivers, but often such panel speakers, subjectively, seem to be low distortion generally.  I listen to Apogee Stage speakers, and they, subjectively, seem clearer and less distorted than any conventional speaker I have ever heard.  Why would this be the case?

The speaker's low nonlinear distortion (about 60 dB down) at higher frequencies 1 KHz, 10 KHz) appears to predict the excellent subjective results.



This is very good performance - most better speakers measure 40-50 dB down.

Here is a comparable measurement for Paradigm Studio 100s:

http://www.soundstagemagazine.com/measurements/paradigm_studio100_v3/



Unfortunately I don't see any Magnapan speakers on this list:

http://www.soundstagenetwork.com/index.php?option=com_content&view=article&id=16&Itemid=18

The published test of the Mgnepan 1.7s suggests to me that they could be excellent at all audible frequencies if proplerly integrated with a good subwoofer, as distasteful as that may seem to planar speaker advocates.
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post #113 of 129 Old 03-19-2014, 11:13 PM
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Quote:
Originally Posted by arnyk View Post

The published test of the Mgnepan 1.7s suggests to me that they could be excellent at all audible frequencies if proplerly integrated with a good subwoofer, as distasteful as that may seem to planar speaker advocates.

Not distasteful to me smile.gif. I own 3.6 Maggies and recently integrated an SVS SB13-Ultra into the mix. I run the Maggies full range (love the bass it does produce) and use the sub's low pass filter at 40 Hz. It has worked wonders for me, especially for organ music and synthesizers that the Maggies just couldn't reproduce.
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post #114 of 129 Old 03-30-2014, 08:50 AM
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I have 3.6R's and although they are not 3.7's I believe they are close enough to recommend the amp's I've been using on them for over 3 years, Wyred4Sound SX1000 Mono-Bloc's http://www.wyred4sound.com/. They are approximately $2400/pair. No protection fault issues and they sound great, to me.
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post #115 of 129 Old 04-08-2014, 07:29 PM
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Everyone,

Usually I enjoy reading threads such as this, but this has been a very frustrating thread. First of all, people need to understand whether or not they understand basic electronics, and if they don't they shouldn't be insisting on things. Its not a bad thing, most people on the planet have not taken an electronics, and that is okay. I'm sure they know lots of other things. But don't then go overboard with 'this is how it should work because someone said so' - and that person may have been right in some senses but taken in isolation the statement can then become incorrect.

So, look, I think 85% of everything said on this thread is wrong. That said, there are people who are saying the right stuff and trying to help other people understand what is going on, yet I don't think it is possible to teach electronics in a single thread. (For example, indeed, there are lower power req's at higher freq than at lower everything else being equal.)


The fact is that the best sounding amplifier for Magnepans are OTL tubes along these lines:

http://www.atma-sphere.com/Products/#MA-2
http://www.joule-electra.com/


And you might note that these put out, in some cases, virtually the same power at 4 Ohms as 8, and in some cases, 60% less. Of course tubes are different beasts than transistors. The doubling of power rule of thumb applies only to transistor amps.

We also aren't talking about how/what kind of music people listen to. A really nice tube amp at 50 watts might be just fine for Jazz, singers, Coffee House Rock, etc. It would likely sound much better at 90 db (which is already quite loud) than an equally priced Class AB amp. But with the equally priced Class AB amp, you might get to 120 db on 1/10th of a second transients, and that might be important to some.


Okay, but those companies above aren't realistic for 99% of AVSForum members. But I want to put it out there - those can't really be bested, there is only slightly different, i.e., DartZeel, VAC, etc. And the larger ones from both companies will have enough dynamic power for any kind of music, and the lower power models will be dynamics limited. Again, the prices are astronomical, we are talking cars and even houses here. so it gets kind of ridiculous.



Now, coming down to what people here might be able to buy, let me say that for Maggies there is one company that acts as a sort of 'reference' which is at moderate price, especially if bought used. Bryston is that company. If you really don't know what to do and have audio nervosa stop thinking about it and just go buy a Bryston and enjoy the music. You need not look much farther.


However, there are a lot of other amp companies out there that are great, and that are better. Here is a list of amps companies I would consider - and btw, if I had to choose one as an ultimate high end solid\-state reference it would easily be Pass Labs. I think it gets 'different' but it doesn't really get better than Pass, unless you sell a car or house and get the tube stuff listed above.



So, allow me to suggest my understanding of some good amps that I've heard for Magnepans without arguing or explaining all of the technical aspects of why:


Class A

Bryston
Pass Labs
Sanders Sound Systems
Krell

(there are very few true Class A amplifiers these days)

Class AB

Bryston
Pass Labs
Musical Fidelity (stay on the high end of their stuff and you'll be fine)


Class D
NuForce (such as 8.5, 9 or ref series)
Spectron


Class AB second tier:
Vincent
Musical Fidelity (medium of their range)
Cambridge Audio (high end of their range only)
NAD (very high end of their range only), etc.

(This segment could have 5 or 8 more added to it, there are plenty here.)




Other Class D amps will have a high-freq problem, and particularly on the 3.7 or 20's you will hear it (ribbon). On the 1.7 and lower you might get away with it. BelCanto and some others are trying, but *today* (this can change any moment), in my opinion, the ice-based amps will not have a suitable high-end for a ribbon tweeter. Some will disagree of course.


If you listen to Jazz or vocals, maybe coffee house rock - anything that isn't heavy symphonic or heavy rock and roll, you might be really shocked what a 50 watt SET tube amp will do as long as it has a 4-ohm output taps and/or you can use zero's which change the impedance requirements.




Well, very briefly let me address the doubling of power and ohms. It isn't that they need to double, it is that doubling power when Ohms halve *often implies massive current reserves* which is the real issue. So you can look here:

https://passlabs.com/images/uploads/manual/x.5_specs.pdf
https://passlabs.com/images/uploads/manual/xa.5_specs.pdf

(you'll quickly discover the difference between the a and non-a - at the same price you can either have ever so slightly better sound, or lots more power)

And take a look at Maximum Output (Amps) and just look at how that compares to the other numbers. Perhaps compare those to the amps you might be thinking of buying. There are two aspects that matter from the phrase 'double watts when Ohms halve' and that is that the amp was built to be stable at low ohms at all (whether at the same watts, or double, or 50% extra) *and* that there are massive current reserves.

Note if you have a low-ohm speaker and a non-low-ohm amp, it can catch on fire. This has happened several times with older Quad's, Apogees and more recently a few have caught fire with the ribbon-bookshelf speaker company Mark and Daniel (measured to 1 Ohm like the Apogees). That has all to do with the design and whether it is rated to X Ohms, not as to whether or not it doubles. The doubling is icing on the cake after validating that the amp is stable at the lower load. You can take the same amp and add output devices to make it double, but it may very well have been stable in the first place. (Such as the Pass Labs X150 not 0.5)

If you really want to rock out, check out the Musical Fidelity Titan - Titan outputs 1kWpc into 8 ohms, 2kWpc into 4 ohms, and approximately 3800Wpc into 2 ohms. (Although if you select 1% THD as your reference and look at the Stereophile graph, it isn't quite that good. Damn good, though!)

(Note my first Pass Labs Amp was, as measured/analyzed by Stereophile - not as claimed by the company - was stable to 1 ohm, and in fact stable at 0.1 ohms, lower eve, and they tested all the way to shorting the speaker terminals and the amp stayed stable. I believe this was the first time Stereophile had ever tested an amp that could do that, this was around 1995 plus or minus a few years and in regards to the Aleph 3.)



I'd much rather see people get a used amp from the list above than getting a 'mid fi' Class AB amp that either can't quite put ut the Amps or doesn't have that magical high-end amp purity to it...


(If you enjoy this as a hobby find a place to try a 50 or even 30 watt SET tube amp - and I'm not saying to buy it or that it is even 'better' - but give it a listen. It might open some ideas or new understanding of amps and music. I've heard damn good sound on 3.6s with 18 watts and it was quite magical. http://vivaaudio.com/en/products/ )
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post #116 of 129 Old 04-08-2014, 07:38 PM
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Everyone,

Usually I enjoy reading threads such as this, but this has been a very frustrating thread. First of all, people need to understand whether or not they understand basic electronics, and if they don't they shouldn't be insisting on things. Its not a bad thing, most people on the planet have not taken an electronics, and that is okay.

Since you brought up the issue, what is your CV like?
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A year and a half of EE. No more, no less. More chemistry than EE. What I did do there had more to do with energy systems, i.e., motors and drives and energy generation than pure circuits, but its all interrelated.
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post #118 of 129 Old 04-09-2014, 05:33 AM
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A year and a half of EE. No more, no less. More chemistry than EE. What I did do there had more to do with energy systems, i.e., motors and drives and energy generation than pure circuits, but its all interrelated.

So is it your intent to school me about amplifiers, given that I have a BS in Engineering (what my school gave out instead of BSEEs) , all but one course of a MS in Engineering, and tons of hands on experience with designing, building, and repairing amplifiers both audio and RF over the past 45 or more years?
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post #119 of 129 Old 04-09-2014, 08:35 AM
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Derogatory terms like "analog bigot", "digiphobe", "internet eggspurts" have nothing to do with electrical engineering.
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post #120 of 129 Old 04-09-2014, 10:45 AM
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Better watch your step lightminer, this Krueger character is a legend in his own mind. *sarcasm*

He has forgotten more about audio than you have ever known.
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