Hifi amps with true 75Watt RMS

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Blacksabbath25

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Vladimir said:
TrevC said:
CnoEvil said:
TrevC said:
Kind of meaningless in a 40W amp really.
Surely it would only be meaningless if speakers remained at one impedance.

Since an amp like that will likely double its output as impedance halves and modern speakers often have impedance that plummets to nearly 3 Ohms, it will, in real world conditions, produce far more than the quoted 40W....and that doesn't take into account its huge reserves of current that will effortlessly cope with sudden dynamic shifts.

Presuming the rated output power of 40W is at 8 ohms (which is a voltage output of around 18 volts), in order to take the quoted peak current of 200A the impedance of the speaker would need to dip to below 0.1 ohm resulting in a power output of around 3600W.

Which is why I said it was kind of meaningless.

Agreed. An overikill, but not completely meaningless.
nice video and this is why budget good to a point
 

TrevC

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Vladimir said:
gasolin said:
Vladimir said:
gasolin said:
TrevC said:
Electro said:
If you want to see an extreme version of the Abrahamsen / Otala/ Lohstroh design philosophy .

then look at this sadly now discontinued Abrahamsen SA1.

40 wpc

40 amps continuous current output

200 amps peak current output .

Kind of meaningless in a 40W amp really.

Isn't it like a diesel engine theres no point in having so much torch with so little horsepower? ;-)

Abrahamsen is just like a diesel engine it doesn't have so much horsepwer,it has alot of torch , that's why it can control any speakers without losing control up to the watt limited of the amp (top speed)

70W in 8 ohms

140W in 4 ohms

280W in 2 ohms

560W in 1 ohm

Now, if you had speakers that dip down very low, the Abe will have a lot more watts in large transient peaks than a 150Wpc in 8 ohms amplifier that has a PSU that can't handle going under 6ohms (sagging voltage rails). Considering that 99% of the time we listen using no more than 10W, this is a smart concept IMO. Again depends on application - the speakers, loudness preference, type of music, digital or analogue (dynamic range) and the room. It's all relevant.

I'd like to see an amp that actually can double the wattage (within the margain of error "few" watt ) as the ohm drops 50%

Would this be less impressive?

78W in 8ohms

144W in 4ohms

282W in 2 ohms

560W in 1 ohm

The way you get perfect doubling down of watts in half the load is by rounding up the number by substracting few watts (by trade regulation laws you can't add, but you can declare less power).

You could use a far less substantial PSU with higher voltage rails and still meet the ideal doubling of power with the halving of impedance spec if you start out by understating the 8 ohm output capability. Would it sound inferior? Of course not.
 

TrevC

Well-known member
Blacksabbath25 said:
Vladimir said:
TrevC said:
CnoEvil said:
TrevC said:
Kind of meaningless in a 40W amp really.
Surely it would only be meaningless if speakers remained at one impedance.

Since an amp like that will likely double its output as impedance halves and modern speakers often have impedance that plummets to nearly 3 Ohms, it will, in real world conditions, produce far more than the quoted 40W....and that doesn't take into account its huge reserves of current that will effortlessly cope with sudden dynamic shifts.

Presuming the rated output power of 40W is at 8 ohms (which is a voltage output of around 18 volts), in order to take the quoted peak current of 200A the impedance of the speaker would need to dip to below 0.1 ohm resulting in a power output of around 3600W.

Which is why I said it was kind of meaningless.

Agreed. An overikill, but not completely meaningless.
nice video and this is why budget good to a point

Nothing to do with budget per se, it's to do with power capability. Sheer muscle. The Dutch guy clearly doesn't think much of SET amplifiers and nor do I, but then i wouldn't call that crappy noise music either. :O)
 

Vladimir

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TrevC said:
Nothing to do with budget per se, it's to do with power capability. Sheer muscle. The Dutch guy clearly doesn't think much of SET amplifiers and nor do I, but then i wouldn't call that crappy noise music either. :O)

In that case you will really hate this one. Abrahamsen + Dunlavy.
heart.gif
Daydream.gif
 

Blacksabbath25

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Vladimir said:
TrevC said:
Nothing to do with budget per se, it's to do with power capability. Sheer muscle. The Dutch guy clearly doesn't think much of SET amplifiers and nor do I, but then i wouldn't call that crappy noise music either. :O)

In that case you will really hate this one. Abrahamsen + Dunlavy.
off topic is he running 2 sets of speakers there if so how as i never see a power amp there and i have never seen a set of speakers with a bottom bass speaker before
 

Vladimir

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Blacksabbath25 said:
off topic is he running 2 sets of speakers there

Nope. The little ones are actually Monitor Audio floorstanders. (designed for audiophiles who have earlobes on their knees)

He is running the Dunlavy speakers only. The scan-speak woofer at the bottom is to ensure really low frequency response while remaining as flat as possible. A bit of an explanation here. Bass frequency spreads spherically and that means placing the woofer on the bottom in order to maintain a thin elongate tall profile of the boxes will not mess with room acoustics. If the woofer was on the side wall it would demand a deeper box and would flex the walls and introduce more cabinet resonances.

John Dunlavy worked as an antenna array designeer for US military for most of his adult life, so that translated into his speaker designs (tall symetrical layouts) for Duntech and later Dunlavy Labs.
 

Andrewjvt

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TrevC said:
radiorog said:
CnoEvil said:
Andrewjvt said:
Who do you think you are? Behave yourself please its only hifi Or at least have a little respect
You can't win against TrevC, as he deals in facts; whereas we mere mortals have to make do with our opinions, which can simply be dismissed.

 Was this a joke?

 It's a fact that all amplifier of similar spec sound the same, even tho they clearly don't? And he said he hasn't even heard the abrahmsen.

 And it's a fact the story of Jesus was a joke? I'm sorry, but I thought there was no concrete proof either way. He was basing his statement on his opinion. Now that's a fact!

I always stick to the facts. It isn't possible that two amplifiers with identical specs can sound different, and it isn't possible that, 2000 years ago, a child can be born of a virgin, get killed and then spring back to life as a zombie god thingy. 

Your small mind
You think you understand but your just small minded and disrespectful of other peoples beliefs and opinions

Cno was right why bother
 

TrevC

Well-known member
Andrewjvt said:
TrevC said:
radiorog said:
CnoEvil said:
Andrewjvt said:
Who do you think you are? Behave yourself please its only hifi Or at least have a little respect
You can't win against TrevC, as he deals in facts; whereas we mere mortals have to make do with our opinions, which can simply be dismissed.

Was this a joke?

It's a fact that all amplifier of similar spec sound the same, even tho they clearly don't? And he said he hasn't even heard the abrahmsen.

And it's a fact the story of Jesus was a joke? I'm sorry, but I thought there was no concrete proof either way. He was basing his statement on his opinion. Now that's a fact!

I always stick to the facts. It isn't possible that two amplifiers with identical specs can sound different, and it isn't possible that, 2000 years ago, a child can be born of a virgin, get killed and then spring back to life as a zombie god thingy.

Your small mind You think you understand but your just small minded and disrespectful of other peoples beliefs and opinions

Cno was right why bother

It's the religious that have the small minds. Open your mind to the beauty and wonder of our godless universe! Imagine a world not torn apart by ignorant tribes and their silly imaginary friends!
 

Andrewjvt

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TrevC said:
Andrewjvt said:
TrevC said:
radiorog said:
CnoEvil said:
Andrewjvt said:
Who do you think you are? Behave yourself please its only hifi Or at least have a little respect
You can't win against TrevC, as he deals in facts; whereas we mere mortals have to make do with our opinions, which can simply be dismissed.

 Was this a joke?

 It's a fact that all amplifier of similar spec sound the same, even tho they clearly don't? And he said he hasn't even heard the abrahmsen.

 And it's a fact the story of Jesus was a joke? I'm sorry, but I thought there was no concrete proof either way. He was basing his statement on his opinion. Now that's a fact!

I always stick to the facts. It isn't possible that two amplifiers with identical specs can sound different, and it isn't possible that, 2000 years ago, a child can be born of a virgin, get killed and then spring back to life as a zombie god thingy.?

Your small mind You think you understand but your just small minded and disrespectful of other peoples beliefs and opinions

Cno was right why bother

It's the religious that have the small minds. Open your mind to the beauty and wonder of our godless universe! Imagine a world not torn apart by ignorant tribes and their silly imaginary friends!

The point im trying to make to you is not who is right or wrong or what i believe in or you. its your lack of respect for other peoples beliefs
This makes you seem self important as if only what you believe is right and dont care about anyone else. Lack of common respect for people.

This is a hifi forum.
If you ever feel the need do this again just tell me how bad my amps wall of sounds sounds like then say all amps sound the same lol.

Im not wanting to get into a seahorse battle in saying please be aware you can hurt peoples feelings. Thats all
 

CnoEvil

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TrevC said:
Where did I say the amp was meaningless??

 
What I'm trying to say, is that you shouldn't write of that kind of "specification" as meaningless, until you hear the effect it has on the sound.
 

Vladimir

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In real estate there is a golden saying "Location, location, location". In audio it would be "Application, application, application". Good luck pushing isobarics or ribbons with a Yamaha A-S501.
 

Andrewjvt

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TrevC said:
CnoEvil said:
TrevC said:
Where did I say the amp was meaningless??

?
What I'm trying to say, is that you shouldn't write of that kind of "specification" as meaningless, until you hear the effect it has on the sound.

How can having a hugely overspecified PSU affect the sound except when running at clipping levels?

Between an over spec'd power supply or an adequate one

Which one would you choose?
 

CnoEvil

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TrevC said:
CnoEvil said:
TrevC said:
Where did I say the amp was meaningless??

?
What I'm trying to say, is that you shouldn't write of that kind of "specification" as meaningless, until you hear the effect it has on the sound.

How can having a hugely overspecified PSU affect the sound except when running at clipping levels?
That is something that you have to hear for yourself..which is why I think specs are interesting, but listening is vital.
 

TrevC

Well-known member
CnoEvil said:
TrevC said:
CnoEvil said:
TrevC said:
Where did I say the amp was meaningless?
What I'm trying to say, is that you shouldn't write of that kind of "specification" as meaningless, until you hear the effect it has on the sound.

How can having a hugely overspecified PSU affect the sound except when running at clipping levels?
That is something that you have to hear for yourself..which is why I think specs are interesting, but listening is vital.

What differences are there to hear?
 

TrevC

Well-known member
Andrewjvt said:
TrevC said:
CnoEvil said:
TrevC said:
Where did I say the amp was meaningless?
What I'm trying to say, is that you shouldn't write of that kind of "specification" as meaningless, until you hear the effect it has on the sound.

How can having a hugely overspecified PSU affect the sound except when running at clipping levels?

Between an over spec'd power supply or an adequate one

Which one would you choose?

Both are adequate.
 

TrevC

Well-known member
Andrewjvt said:
TrevC said:
Andrewjvt said:
TrevC said:
radiorog said:
CnoEvil said:
Andrewjvt said:
Who do you think you are? Behave yourself please its only hifi Or at least have a little respect
You can't win against TrevC, as he deals in facts; whereas we mere mortals have to make do with our opinions, which can simply be dismissed.

Was this a joke?

It's a fact that all amplifier of similar spec sound the same, even tho they clearly don't? And he said he hasn't even heard the abrahmsen.

And it's a fact the story of Jesus was a joke? I'm sorry, but I thought there was no concrete proof either way. He was basing his statement on his opinion. Now that's a fact!

I always stick to the facts. It isn't possible that two amplifiers with identical specs can sound different, and it isn't possible that, 2000 years ago, a child can be born of a virgin, get killed and then spring back to life as a zombie god thingy.

Your small mind You think you understand but your just small minded and disrespectful of other peoples beliefs and opinions

Cno was right why bother

It's the religious that have the small minds. Open your mind to the beauty and wonder of our godless universe! Imagine a world not torn apart by ignorant tribes and their silly imaginary friends!

The point im trying to make to you is not who is right or wrong or what i believe in or you. its your lack of respect for other peoples beliefs This makes you seem self important as if only what you believe is right and dont care about anyone else. Lack of common respect for people.

This is a hifi forum. If you ever feel the need do this again just tell me how bad my amps wall of sounds sounds like then say all amps sound the same lol.

Im not wanting to get into a seahorse battle in saying please be aware you can hurt peoples feelings. Thats all

Seahorse battle?
 

Vladimir

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TrevC said:
Andrewjvt said:
TrevC said:
Andrewjvt said:
TrevC said:
radiorog said:
CnoEvil said:
Andrewjvt said:
Who do you think you are? Behave yourself please its only hifi Or at least have a little respect
You can't win against TrevC, as he deals in facts; whereas we mere mortals have to make do with our opinions, which can simply be dismissed.

Was this a joke?

It's a fact that all amplifier of similar spec sound the same, even tho they clearly don't? And he said he hasn't even heard the abrahmsen.

And it's a fact the story of Jesus was a joke? I'm sorry, but I thought there was no concrete proof either way. He was basing his statement on his opinion. Now that's a fact!

I always stick to the facts. It isn't possible that two amplifiers with identical specs can sound different, and it isn't possible that, 2000 years ago, a child can be born of a virgin, get killed and then spring back to life as a zombie god thingy.

Your small mind You think you understand but your just small minded and disrespectful of other peoples beliefs and opinions

Cno was right why bother

It's the religious that have the small minds. Open your mind to the beauty and wonder of our godless universe! Imagine a world not torn apart by ignorant tribes and their silly imaginary friends!

The point im trying to make to you is not who is right or wrong or what i believe in or you. its your lack of respect for other peoples beliefs This makes you seem self important as if only what you believe is right and dont care about anyone else. Lack of common respect for people.

This is a hifi forum. If you ever feel the need do this again just tell me how bad my amps wall of sounds sounds like then say all amps sound the same lol.

Im not wanting to get into a seahorse battle in saying please be aware you can hurt peoples feelings. Thats all

Seahorse battle?

Micropenis inadequacy challenge.
 

Blacksabbath25

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Sep 20, 2015
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Vladimir said:
Blacksabbath25 said:
off topic is he running 2 sets of speakers there

Nope. The little ones are actually Monitor Audio floorstanders. (designed for audiophiles who have earlobes on their knees)

He is running the Dunlavy speakers only. The scan-speak woofer at the bottom is to ensure really low frequency response while remaining as flat as possible. A bit of an explanation here. Bass frequency spreads spherically and that means placing the woofer on the bottom in order to maintain a thin elongate tall profile of the boxes will not mess with room acoustics. If the woofer was on the side wall it would demand a deeper box and would flex the walls and introduce more cabinet resonances.

John Dunlavy worked as an antenna array designeer for US military for most of his adult life, so that translated into his speaker designs (tall symetrical layouts) for Duntech and later Dunlavy Labs.
thanks for the info
 

Andrewjvt

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iQ Speakers said:
It's why everybody that cares to take a chance, makes the effort to listen to one, falls in love with it. Its the control over bass notes the way they start and stop very accuratly and quickly. Which in turn lets you hear the "twinkly bits" the fingers on strings sliding, the breath a singer takes, the triangle, the Tambourine floating out of know where all accuratly placed. Or if you listen to heavier rock tracks its not presented as if its been blitzed through a blender. Its the kind of sound people spend a fourtune obtaining. Thats what a heavy over spec'ed PSU does for me and other that hear one!

Well put
 

CnoEvil

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TrevC said:
What differences are there to hear?
There are 2 things that I know.

- You have stated, that the only components that make a meaningful difference to the sound, are speakers and cartridges. You think that if an amp is sufficient to drive the speakers, there will be negligible difference between any of them....this is the reason that you give for not going out and hearing different amps.
With this mindset, you are certainly not going to accept that this amp's impressive spec will make a difference.

- Any description that I give about the advantages, is a complete waste of effort, as it will simply be dismissed by you as subjective nonsense; so what's the point. You have no intention of changing your opinion, or listening for yourself....and I am certainly not going to change my view. Our two positions are so irreconcilably different, that there is nothing further to say.
 

iQ Speakers

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It's why everybody that cares to take a chance, makes the effort to listen to one, falls in love with it. Its the control over bass notes the way they start and stop very accuratly and quickly. Which in turn lets you hear the "twinkly bits" the fingers on strings sliding, the breath a singer takes, the triangle, the Tambourine floating out of know where all accuratly placed. Or if you listen to heavier rock tracks its not presented as if its been blitzed through a blender. Its the kind of sound people spend a fourtune obtaining. Thats what a heavy over spec'ed PSU does for me and others that hear one!
 

TrevC

Well-known member
CnoEvil said:
TrevC said:
What differences are there to hear?
There are 2 things that I know.

- You have stated, that the only components that make a meaningful difference to the sound, are speakers and cartridges. You think that if an amp is sufficient to drive the speakers, there will be negligible difference between any of them....this is the reason that you give for not going out and hearing different amps. With this mindset, you are certainly not going to accept that this amp's impressive spec will make a difference.

- Any description that I give about the advantages, is a complete waste of effort, as it will simply be dismissed by you as subjective nonsense; so what's the point. You have no intention of changing your opinion, or listening for yourself....and I am certainly not going to change my view. Our two positions are so irreconcilably different, that there is nothing further to say.

I have listened to amplifiers my entire life and found the differences very subtle /imagined at best. Providing an amplifier is adequately powered and has plenty of caps to soak up the transient peaks and hum the transformer in the PSU itself (which is the main thing) will make no difference when the amp is used below clipping levels. Will a torch running on 8 AA batteries be less bright than the same torch wired to a car battery? Of course not.
 

iQ Speakers

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In answer to the torch analagy if I'm being kind no. The bulb has no input and is a fixed load. However what makes a 100W or 500W bulb brighter than a 40W one? Both 12V, one will need alot more current, can the 8 AA bateries deliver?
 

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