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post #1 of 129 Old 11-05-2013, 12:51 PM - Thread Starter
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I need more power for my magnepan 3.7 speakers. I would appreciate any recommendations.
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post #2 of 129 Old 11-05-2013, 01:11 PM
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http://www.magnepan.com/faq#power
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post #3 of 129 Old 11-05-2013, 11:41 PM
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Whats the budget for the new amp?

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post #4 of 129 Old 11-05-2013, 11:59 PM
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How much power does your current amp provide?

"I realize that somebody playing free music isn't as commercial as a hamburger stand. But is it because you can eat a hamburger and hold it in your hand and you can't do that with music? Is it too free to control?" - Don Van Vliet (aka Captain Beefheart) discussing commercial success in the music biz


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post #5 of 129 Old 11-06-2013, 04:21 AM
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Quote:
Originally Posted by Ratman View Post

http://www.magnepan.com/faq#power

How's that for double speak? They ask the question and don't answer it. At least they could have provided a chart with suggestions based on average listening level and distance.
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post #6 of 129 Old 11-06-2013, 03:05 PM
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Quote:
Originally Posted by ABQ2013 View Post

I need more power for my magnepan 3.7 speakers. I would appreciate any recommendations.

How do you know that you need more power?
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post #7 of 129 Old 11-06-2013, 05:47 PM
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Bueller?

Bueller?

Bueller?

Hmm.

I just love it when someone starts a thread - then goes missing...

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post #9 of 129 Old 11-06-2013, 09:48 PM - Thread Starter
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I have 7-channel Marantz 8077 amplifiers rated (?) at 150 watts per channel. I also have 2 Submersive subs with their own amplifiers. When I play at 70 on the read out (I don't know how this related to dBs) of the Marantz AV8801 Pre-Pro, the 8077 amps shut down as I approach the 75 read out. I have concluded that I need more power, at least for the R/L front speakers (I also have Magnepan 1.7 as sides and the CCR center speaker). I have a budget of about $3000 for buying additional amps (maybe a Parasound Halo amplifier). I really don't trust the dealer who sold me the marantz and magnepan kit. Any ideas of alternate approaches would be appreciated.
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post #10 of 129 Old 11-06-2013, 10:51 PM
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I took a look at the specs for the MM8077 amp but Marantz does not list whether it can drive 4ohm loads. They spec it for 6ohms and 180wpc. Your current amp is running out of gas!

The trouble with Magnepan is the low impedance dips of 3ohms - and often even less. Planar speakers aren't easy on amps - you need something that is designed for low impedance loads. I'd look at something like the Emotiva XPA-100 mono-block amps. At $600 for a pair (currently on sale) thats a very good bargain IMO. Don't let the low prices of the Emotiva amps fool you - they are quite stout. They sell other more powerful amps but unless you are listening at very high SPL's I doubt you need more than the 400wpc into 4ohms of the XPA-100 amps. If you want a single box amp solution the XPA-2 has made many planar speaker owners very happy.

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post #11 of 129 Old 11-07-2013, 06:05 AM
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Quote:
Originally Posted by ABQ2013 View Post

I have 7-channel Marantz 8077 amplifiers rated (?) at 150 watts per channel. I also have 2 Submersive subs with their own amplifiers. When I play at 70 on the read out (I don't know how this related to dBs) of the Marantz AV8801 Pre-Pro, the 8077 amps shut down as I approach the 75 read out. I have concluded that I need more power, at least for the R/L front speakers (I also have Magnepan 1.7 as sides and the CCR center speaker). I have a budget of about $3000 for buying additional amps (maybe a Parasound Halo amplifier). I really don't trust the dealer who sold me the marantz and magnepan kit. Any ideas of alternate approaches would be appreciated.

MM8077 has a poor reputation for value and performance.

This review
http://www.soundandvision.com/content/marantz-av8801-surround-processor-amp-mm8077-amplifier-ht-labs-measures

Shows it to be barely a $2,399 100 wpc @ 8 ohm device with even just 2 channels driven.



Notice the knee at 100 wpc @ 8 ohms. That's my estimate of its power output.

Now, look at this:



This is a similar test run on a $450 AVR.

Please notice the knee at 75 watts @ 8 ohms. That's my estimate of its power output. Note that the $450 AVR delivers about 75% or only 2 dB (4 clicks) less power than the the $2,399 amplifier.

Here is a similar report for the Emotiva XPA 100



I would put the same knee as I used to establish power levels above at about 180 watts per channel, which is only 2.5 dB or so (5 clicks) louder than the Marantz AV8077.

If you read this article about the mm8807:

http://www.soundandvision.com/content/marantz-av8801-surround-processor-amp-mm8077-amplifier-ht-labs-measures

it says:

"This graph shows that the MM8077’s left amplifier channel, with two channels driving 8-ohm loads, reaches 0.1 percent distortion at 128.4 watts and 1 percent distortion at 150.3 watts. Into 4 ohms, the amplifier reaches 0.1 percent distortion at 220.2 watts and 1 percent distortion at 241.8 watts."

This should lay to rest any speculation that it is not competent with 4 ohm loads.

I conclude that it is possible that your particular mm8077 may be faulty in a unique way for that sample, if you find it as easy to put into protect mode as you say. I agree with other editorial comment saying that it is not a particularly good value on the best day of its life. I disagree with the recommendation of the Emotiva XPA100 on the grounds that it cannot be expected to be enough louder than what you have (presuming it is not faulty). I would recommend having competent technical people check it out, because despite being a poor value, it also seems to be underperforming its potential if we can believe independent tests of it.
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post #12 of 129 Old 11-07-2013, 03:19 PM
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Bryston

Overrated.
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post #14 of 129 Old 11-07-2013, 06:25 PM
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Nice warranty, though.

"I realize that somebody playing free music isn't as commercial as a hamburger stand. But is it because you can eat a hamburger and hold it in your hand and you can't do that with music? Is it too free to control?" - Don Van Vliet (aka Captain Beefheart) discussing commercial success in the music biz


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post #15 of 129 Old 11-07-2013, 09:23 PM
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Unfortunately no longer transferable.

Well build, excellent service...still, 3500 for a 150W amp...I had several.
from 4B/4 BST/2B
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post #16 of 129 Old 11-07-2013, 10:17 PM
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Originally Posted by kraut View Post

Unfortunately no longer transferable.

Well build, excellent service...still, 3500 for a 150W amp...I had several.
from 4B/4 BST/2B

That 20 year transferable warranty was one of the few things in their favor IMHO, but way expensive for the wattage in any case....

"I realize that somebody playing free music isn't as commercial as a hamburger stand. But is it because you can eat a hamburger and hold it in your hand and you can't do that with music? Is it too free to control?" - Don Van Vliet (aka Captain Beefheart) discussing commercial success in the music biz


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post #17 of 129 Old 11-08-2013, 12:50 AM
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Arny makes a good point about the chart. I once read a review about a guy who tried to drive his magnepans with a 2,500 krell integrated amp and said it went into protection mode or I would suggest krell for other speakers. from what I hear a lot of amps have trouble with magnepan because of how low the independence dips down to. What about a McIntosh Nad or a Rotel? Would any of those handle those speakers? I have seen Nad do okay with some hard to push speakers, but never saw them hooked up to a magnepan speaker before. what about sim audio? is that a good match for him? once I heard a sim audio integrated amp hooked up to some very hard to drive vienna acoustics speakers.
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post #18 of 129 Old 11-08-2013, 04:52 AM
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Quote:
Originally Posted by lovinthehd View Post

Quote:
Originally Posted by kraut View Post

Unfortunately no longer transferable.

Well build, excellent service...still, 3500 for a 150W amp...I had several.
from 4B/4 BST/2B

That 20 year transferable warranty was one of the few things in their favor IMHO, but way expensive for the wattage in any case....

I have a friend that is about half way through one such warranty and has sent his amp back twice. My preference is for no trouble, which I frequently enjoy from far, far lest costly but very good and robust equipment.

These two products are unlikely to sound different in a DBT:

http://bryston.com/products/power_amps/4BSST-2.html $4995

http://www.qscaudio.com/products/amps/gx/ - $299.95
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post #19 of 129 Old 11-08-2013, 06:47 AM
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Hi,

it seems I recollected incorrectly. The warranty is still transferable, but no longer unlimited. Certain conditions apply:
Quote:
As of 2006-02-22 Bryston will only warranty Bryston products purchased through authorized Bryston dealers. Bryston products with a date code of 0608 or higher (date code format is “yyww”, where “yy” is the two least significant digits of the year and “ww” is the week of the year) must be accompanied by a copy of the bill-of-sale from a Bryston authorized dealer to qualify for warranty service. The warranty is transferable from the original owner to a subsequent owner as long as a copy of the bill-of-sale from the original authorized Bryston dealer accompanies the re-sale. The copy of the bill of sale to any subsequent owner need ONLY include the Name of the Bryston Authorized Dealer and the Model and Serial number of the Bryston product. The warranty will only be honoured in the country of the original purchase unless otherwise pre-authorized by Bryston..
So I was not correct to the extent that warranty is not transferable, but that certain conditions to a previously unconditional 20year warranty apply.

I had trouble with a previously owned 4B ST once during five or six year ownership.

I also own a quad 405 that still runs after over 40 years still without problems.
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post #20 of 129 Old 11-13-2013, 05:01 PM
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post #21 of 129 Old 03-07-2014, 02:11 PM
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will this work?

 

Sony STR-DA5800ES A/V Receiver HT Labs Measures

 
HT Labs Measures

Two channels driven continuously into 8-ohm loads:
0.1% distortion at 128.5 watts
1% distortion at 171.4 watts

Five channels driven continuously into 8-ohm loads:
0.1% distortion at 110.3 watts
1% distortion at 134.7 watts

Seven channels driven continuously into 8-ohm loads:
0.1% distortion at 98.5 watts
1% distortion at 118.7 watts

Analog frequency response in Analog Direct mode:
–0.05 dB at 10 Hz
–0.01 dB at 20 Hz
–0.08 dB at 20 kHz
–3.18 dB at 50 kHz

Analog frequency response with signal processing:
–0.35 dB at 10 Hz
–0.12 dB at 20 Hz
–3.25 dB at 20 kHz
–60.38 dB at 50 kHz

913sonyavr.meas.jpg

This graph shows that the STR-DA5800ES’s left channel, from CD input to speaker output with two channels driving 8-ohm loads, reaches 0.1 percent distortion at 128.5 watts and 1 percent distortion at 171.4 watts. Into 4 ohms, the amplifier reaches 0.1 percent distortion at 174.3 watts and 1 percent distortion at 242.6 watts.

Response from the multichannel input to the speaker output measures –0.15 decibels at 10 hertz, –0.05 dB at 20 Hz, –0.11 dB at 20 kilohertz, and –3.22 dB at 50 kHz. THD+N from the CD input to the speaker output was less than 0.029 percent at 1 kHz when driving 2.83 volts into an 8-ohm load. Crosstalk at 1 kHz driving 2.83 volts into an 8-ohm load was –65.56 dB left to right and –72.94 dB right to left. The signal-to-noise ratio with an 8-ohm load from 10 Hz to 24 kHz with “A” weighting was –102.71 dBrA.

From the Dolby Digital input to the loudspeaker output, the left channel measures –0.06 dB at 20 Hz and –0.39 dB at 20 kHz. The center channel measures –0.04 dB at 20 Hz and –0.44 dB at 20 kHz, and the left surround channel measures –0.04 dB at 20 Hz and –0.43 dB at 20 kHz. From the Dolby Digital input to the line-level output, the LFE channel is +0.01 dB at 20 Hz when referenced to the level at 40 Hz and reaches the upper 3-dB down point at 105 Hz and the upper 6-dB down point at 111 Hz.—MJP

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post #22 of 129 Old 03-08-2014, 04:46 PM
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Here is what Magnepan recommends (from their website):
Everyone understands they need plenty of power, but the role of power supply is not understood. There is one important concept you need to understand when shopping for an amplifier or receiver---and it is somewhat like understanding "good" and "bad" cholesterol. The ratio is very important. An Gold Standard for an amplifier would be to double the power at 4 ohms. This concept is important even if you are buying an 8 ohm speaker. If the amplifier is rated at 80 watts at 8 ohms, it should (ideally) produce 160 watts at 4 ohms (or close to it). None of the receivers will do that. However, this is the benchmark of a good amplifier design. A 10 watt amplifier that produces 20 watts at 4 ohms "speaks volumes" about the PHILOSOPHY of the designer. (But, of course, it does not tell you if a 10 watt amplifier is enough for your room.)

A good receiver might produce 30-40% more power at 4 ohms. Most receiver manufacturers don't want to talk about 4 ohm ratings because they have cut the "guts" out of their products to keep the cost down. Some receivers produce the same power at 4 ohms as the 8 ohm ratings. Or they use a switch on the back for 4 ohms to reduce the power and to prevent the receiver from self destructing. Others warn against 4 ohm speakers and will only offer a 6 ohm power rating. Regardless of what speaker you buy, we don't recommend any of these receivers. There are a few manufacturers making receivers with good 4 ohm capability. But, we can't keep up with who's doing what. All you have to remember is to ask-- "What is the 4 ohm power rating?" If the 4 ohm rating isn't available, find another model or brand. It may take some digging to find the 4 ohm rating, but there are a number of receivers on the market that are rated for 4 ohms. For example, the THX rating requires that the amplifier section must be able to drive 4 ohms continuously. Even an inexpensive receiver like the 50 watt NAD C725 BEE (suggested retail of $799) is advertised to be stable with impedances down to 1 ohm and has peak power of 200 watts. So, don't be fooled by pretty front panels. Its what is on the inside that counts.


Based on what Magnepan says and others have commented, the OP will need a better amp to drive the 3.7. If he doesn't, he will be blowing the fuses or (worse) the tweeters of the 3.7s.

I have used Classe amps with maggies for years. Classe and Magnepan work very well together. I had a Classe Ca-300 with my 3.6s and enjoyed the sound very much.
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post #23 of 129 Old 03-08-2014, 07:46 PM
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Quote:
Originally Posted by Nicoff View PostHere is what Magnepan recommends (from their website):
Everyone understands they need plenty of power, but the role of power supply is not understood. There is one important concept you need to understand when shopping for an amplifier or receiver---and it is somewhat like understanding "good" and "bad" cholesterol. The ratio is very important. An Gold Standard for an amplifier would be to double the power at 4 ohms. This concept is important even if you are buying an 8 ohm speaker. If the amplifier is rated at 80 watts at 8 ohms, it should (ideally) produce 160 watts at 4 ohms (or close to it). None of the receivers will do that. However, this is the benchmark of a good amplifier design. A 10 watt amplifier that produces 20 watts at 4 ohms "speaks volumes" about the PHILOSOPHY of the designer. (But, of course, it does not tell you if a 10 watt amplifier is enough for your room.)

A good receiver might produce 30-40% more power at 4 ohms. Most receiver manufacturers don't want to talk about 4 ohm ratings because they have cut the "guts" out of their products to keep the cost down. Some receivers produce the same power at 4 ohms as the 8 ohm ratings. Or they use a switch on the back for 4 ohms to reduce the power and to prevent the receiver from self destructing. Others warn against 4 ohm speakers and will only offer a 6 ohm power rating. Regardless of what speaker you buy, we don't recommend any of these receivers. There are a few manufacturers making receivers with good 4 ohm capability. But, we can't keep up with who's doing what. All you have to remember is to ask-- "What is the 4 ohm power rating?" If the 4 ohm rating isn't available, find another model or brand. It may take some digging to find the 4 ohm rating, but there are a number of receivers on the market that are rated for 4 ohms.
Dah!
For example, the THX rating requires that the amplifier section must be able to drive 4 ohms continuously. Even an inexpensive receiver like the 50 watt NAD C725 BEE (suggested retail of $799) is advertised to be stable with impedances down to 1 ohm and has peak power of 200 watts. So, don't be fooled by pretty front panels. Its what is on the inside that counts.

Based on what Magnepan says and others have commented, the OP will need a better amp to drive the 3.7. If he doesn't, he will be blowing the fuses or (worse) the tweeters of the 3.7s.

I have used Classe amps with maggies for years. Classe and Magnepan work very well together. I had a Classe Ca-300 with my 3.6s and enjoyed the sound very much.

Yes, of course when I plug in my MMG ($600) into my CA-M600 ($14,000) amps they sound rather good! 

 

The idea of a 4600 speaker is to find an amp in the same price range

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Originally Posted by wse View Post

Yes, of course when I plug in my MMG ($600) into my CA-M600 ($14,000) amps they sound rather good! 

The idea of a 4600 speaker is to find an amp in the same price range

In my post, I was quoting Magnepan's website (all italics). That was not my opinion; that is what Magnepan recommends in their own words.

The idea is NOT to find an amp in the same price-range. Rather, it is to find an amp that works well with the 3.7s. There are amps for less than half that money that work with it (the Classe CA-300 that I mentioned costs about $2k now; when new, that amp was still less than $4.5K.). You should sell your M600, buy a cheaper amp, and then you will have lots of change left over for beer.
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post #25 of 129 Old 03-08-2014, 08:27 PM
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Quote:
Originally Posted by Nicoff View PostIn my post, I was quoting Magnepan's website (all italics). That was not my opinion; that is what Magnepan recommends in their own words. The idea is NOT to find an amp in the same price-range. Rather, it is to find an amp that works well with the 3.7s. There are amps for less than half that money that work that work with it (the Classe CA-300 that I mentioned costs about $2k now; when new, that amp was still less than $4.5K.).
Yes I know I just think Magnepan is full of it! Nothing against you
You should sell your M600, buy a cheaper amp, and then you will have lots of change left over for beer.
I don't drink beer, enjoy!
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post #26 of 129 Old 03-08-2014, 08:40 PM
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post #27 of 129 Old 03-09-2014, 05:52 AM
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Quote:
Originally Posted by Nicoff View Post

Here is what Magnepan recommends (from their website):
Everyone understands they need plenty of power, but the role of power supply is not understood. There is one important concept you need to understand when shopping for an amplifier or receiver---and it is somewhat like understanding "good" and "bad" cholesterol. The ratio is very important. An Gold Standard for an amplifier would be to double the power at 4 ohms. This concept is important even if you are buying an 8 ohm speaker. If the amplifier is rated at 80 watts at 8 ohms, it should (ideally) produce 160 watts at 4 ohms (or close to it). None of the receivers will do that. However, this is the benchmark of a good amplifier design. A 10 watt amplifier that produces 20 watts at 4 ohms "speaks volumes" about the PHILOSOPHY of the designer. (But, of course, it does not tell you if a 10 watt amplifier is enough for your room.)

This notion that good amplifiers will have a 4ohm rating that is twice it's 8ohm rating strikes me as nonsense. ..And it also seems easily gamed. ..So if an amp produces 200 watts at 4ohms, and 120 at 8ohms, what's to stop the manufacturer from simply understating their 8ohm slightly at 100w so as to hit the magical "doubling" number that audiophiles find so important??
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post #28 of 129 Old 03-09-2014, 08:50 AM
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Quote:
Originally Posted by syd123 View Post

Quote:
Originally Posted by Nicoff View Post

Here is what Magnepan recommends (from their website):
Everyone understands they need plenty of power, but the role of power supply is not understood. There is one important concept you need to understand when shopping for an amplifier or receiver---and it is somewhat like understanding "good" and "bad" cholesterol. The ratio is very important. An Gold Standard for an amplifier would be to double the power at 4 ohms. This concept is important even if you are buying an 8 ohm speaker. If the amplifier is rated at 80 watts at 8 ohms, it should (ideally) produce 160 watts at 4 ohms (or close to it). None of the receivers will do that. However, this is the benchmark of a good amplifier design. A 10 watt amplifier that produces 20 watts at 4 ohms "speaks volumes" about the PHILOSOPHY of the designer. (But, of course, it does not tell you if a 10 watt amplifier is enough for your room.)

This notion that good amplifiers will have a 4ohm rating that is twice it's 8ohm rating strikes me as nonsense. ..And it also seems easily gamed. ..So if an amp produces 200 watts at 4ohms, and 120 at 8ohms, what's to stop the manufacturer from simply understating their 8ohm slightly at 100w so as to hit the magical "doubling" number that audiophiles find so important??

+1.

"Doubling down" is IME an audiophile myth. I am personally disappointed to see Magnepan which is a company that I have respected for their fairly unique technology hopping onto the "Doubling Down" bandwagon. I'm sure it pleases their dealers and their friendly neighbors at Audio Research.

Other than the use of superconductive parts every amplifier is going to have internal resistive losses and they are going to increase as current increases as load impedance decreases.

Therefore, true "Doubing down" requires the audio equivalent of perpetual motion. I've tested some power amplifiers such as the Pass Threshold 4e and found that while they can have impressive performance at 4 and even 2 ohms, but they too find real doubling down to be elusive.

IME the manufacturer recommended fuses of large Magnepans can be effectlively blown while playing regular music using a good 100 wpc amplifier, so a credible AVR should be sufficient for all reasonable use.
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post #29 of 129 Old 03-09-2014, 09:45 AM
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In this particular case the power doubling in 4 Ohm is good advice. However it is not really a good indicator to determine the quality of an amplifier in general.
Power levels are usually rated at 8Ohm. If the 4 Ohm power rating doesn't double up it merely indicates that it will likely clip at lower amplitude due to current limiting.

A 200 Watt power amplifier rated 300Watt into 4Ohm will deliver the same SPL as a 150Watt amplifier that manages to double it's power into a 4 Ohm load.

If the amplifier design skimps on protection circuits and/or adequate cooling under prolonged overload the amplifier may even fail eventually.

The 4 Ohm load from a ribbon just needs more current to reach the desired SPL.
For a full range ribbon this 4 Ohm impedance is actually decent. the behemoths from Apogee went down to 1 Ohm....
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post #30 of 129 Old 03-09-2014, 09:51 AM
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Quote:
Originally Posted by Frank Derks View Post

In this particular case the power doubling in 4 Ohm is good advice..

How can it be good advice if it is both physically impossible and oh by the way has never been actually observed? ;-)

Doubling down does show up on spec sheets but real world tests show that it is based on systematic misrepresentation.

Just for grins I think I know how to build a power amp that does indeed double down on the test bench, but so far that knowledge has never showed up on anybody's test bench or in a known product.
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Magnepan Mg 3 7 , Marantz Mm8077 Power Amplifier , Marantz Av8801
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