watt per channel is irrevelent!!

[Vladimir]

Everyone with a mobile device hated me for typing that. But now they shifted hate to you for quoting it. Thanks!

 

[hybridauth_Facebook_664715932]

55wpc @ 8ohms

80wpc @ 4ohms

My mistake,
Thanks for the correction

 

[matt49]

Loudspeakers are current driven devices, not voltage.

Does that apply to your speakers?

 

[steve_1979]

The power of an amplifier does make a difference to how loud it will go. But comparing a 40 watt amp to a 55 watt amp based purely on the manufactures quoted figures is pointless as they may not have been measured in the same way (different levels of THD for example) and manufactures have a nasty habit of massaging their figures and being economical with the truth.

Is that 55 watt amplifier really more powerful than the 40 watt one? Has anyone actually measured them both using exactly the same criteria?

 

[SteveR750]

BTW few months ago I heard on BBC radio that a British engineer invented a real world current based (not voltage based) amplifier. This bypasses all the issues with amplifiers ability to drive speakers. This probably requires specially designed output devices for current.

Can't wait to see a commercial version of this unit, which may not be for audio initially.

Is this what you're referring to?

 

[Frank Harvey]

Watts per channel (real WPC) makes a huge difference.

Going from a 60 WPC Arcam to a 200 WPC Lyngdorf demonstrated this pretty clearly back when I ran them.

That's probably more down to comparing a Class A/B amplifier to a Class D one.

 

[pauln]

I've compared Naomi to Charlie and have decided that I prefer Naomi - a much smoother presentation despite Charlie sounding subjectively louder, although that may be due to possible class A input sensitivity being higher. YVMV. I've not done a blind test but am certain I could tell one from the other blindfolded and indeed blind drunk.

Of course, me being of a certain age, I do have a nostalgic affection for Den and Angie but looking back I think that they were quite 'shouty' and a bit too 'in yer face'.

 

[MeanandGreen]

The thing to remeber is that to get an increase of 3db an amplifier needs to double its power output. Speakers are very inefficient devices in general. Obviously speaker sensitivity plays a very big role in how much volume you will get for your watts.

Realistically most of us probably only listen to few watts of continuous amplifier power.

 

[expat_mike]

Hence I found that the watts per c/h is irreverent to how loud a system can sound.

It appears that you are claiming that a system will sound just as loud, regardless of whether you supply the speakers with 0.000001W, 1W, 10W or 100W etc.

Amazing!

Have you patented this technology yet?

You're just being pedantic and bloody awkward for awkward's sake. It's pretty obvious what he was meaning. God there are some times when contributors on internet forums irritate the hell out of me.

Major I am sorry that you feel that way - my attempt at humour was lost on you, but the OP understood it as humour. I am an engineer by profession, and ambiguity in statements, is an opportunity for other people to misunderstand what the statement really means.

 

[Vladimir]

Is this what you're referring to?

That is an opamp from the 80's. This was a full blown amplifier and recently promoted. Can't seem to find it on the BBC past program archives.

 

[Vladimir]

A Watt is a Watt.

100W = 1V * 100A or 100W = 100V * 1A. Depending on speaker design, one of those 100W will be preferable. Check Matt's link.

Loudspeakers are current driven devices, not voltage.

Does that apply to your speakers?

 

[hybridauth_Facebook_664715932]

A very big thank you to you guys.
I am so glad I started that thread. In last 24 hours I have learnt more than I had known in last 20 years about my 1 of very few hobby.

 

[CnoEvil]

I like to keep it fairly simple ie.

- Competence of the power supply ie. Look at the power into 8 Ohms and 4 Ohms, and if it gets close to doubling, that is a good sign.

- Speaker sensitivity is key to getting volume.

- Speakers with plummeting impedance need amps with robust power supplies.

- Watts are certainly important, but as been said above, it is not the full story. The interaction between amp/speakers is what really counts. A handful of Watts can sound amazingly loud through very sensitive speakers.

 

[fr0g]

Watts per channel (real WPC) makes a huge difference.

Going from a 60 WPC Arcam to a 200 WPC Lyngdorf demonstrated this pretty clearly back when I ran them.

That's probably more down to comparing a Class A/B amplifier to a Class D one.

Not really. The Arcam would run out of steam at the volumes I wanted. The Lyngdorf wouldn't. At medium volume I probably couldn't tell them apart.

The only reason I upgraded is because at the time, my system was in a large(ish) room (10m x 5m) and I wanted more!

Luckily I don't have any issues with getting huge volume from my Avis. I would go deaf before they started to struggle. And they cost less than my Lyngdorf amp did!

 

[pauln]

A Watt is a Watt.

100W = 1V * 100A or 100W = 100V * 1A. Depending on speaker design, one of those 100W will be preferable. Check Matt's link.

I'm sure you know that a Watt is a unit of power, if you want to talk about voltage or current then be specific. One Watt is always one Watt no matter if it's 1V * 1A or 100V * .01A.

 

[Vladimir]

Of course. When all things being equal.

The difference between math and engineering is in math, when you shoot an arrow, it never hits the tree. It travels half way, then half of that, half of that, half of that... and never reaches the tree. In engineering the arrow always hits the tree, math be damned.

 

[Laurens_B]

Of course. When all things being equal.

The difference between math and engineering is in math, when you shoot an arrow, it never hits the tree. It travels half way, then half of that, half of that, half of that... and never reaches the tree. In engineering the arrow always hits the tree, math be damned.

I must disagree with this. In the limit with the amount of iterations approaching infinity (which it will in reality), the arrow actually hits the tree, mathematically. It's a convergent series in mathematics.

 

[Vladimir]

LB

BTW I have BA in Sociology, therefore... take my posts with a healthy dose of humor and skepticism.

 

[Laurens_B]

LB

BTW I have BA in Sociology, therefore... take my posts with a healthy dose of humor and skepticism.

Haha, you're quite familiar with mathematics and physics for someone with a BA in sociology.

I'm not sure where I would fit in that chain, as an aerospace engineer, I think somewhere among the chemists. Haven't seen many claimed mathematicians here unfortunately, they might have some interesting views on cables though...

 

[Vladimir]

I'm not sure where I would fit in that chain, as an aerospace engineer...

A physicist with an actual job and a girlfriend. Not on that graph for sure.

 

[Laurens_B]

I'm not sure where I would fit in that chain, as an aerospace engineer...

A physicist with an actual job and a girlfriend. Not on that graph for sure.

*lol*

 

[BigH]

The 50A is 55w at 8Ohms not 4, at 4Ohms its 85W I believe. What you should say is manufacturers figures are not always reliable. According to Stereophile the 50A is over 60W at 8 ohms amd about 85 at 4Ohms.

Yes it does matter.

 

[steve_1979]

I like to keep it fairly simple ie.

- Competence of the power supply ie. Look at the power into 8 Ohms and 4 Ohms, and if it gets close to doubling, that is a good sign.

- Speaker sensitivity is key to getting volume.

- Speakers with plummeting impedance need amps with robust power supplies.

- Watts are certainly important, but as been said above, it is not the full story. The interaction between amp/speakers is what really counts. A handful of Watts can sound amazingly loud through very sensitive speakers.

+1

There I go agreeing with you again. *shok*

 

[steve_1979]

LB

BTW I have BA in Sociology, therefore... take my posts with a healthy dose of humor and skepticism.

My girlfriend has a PhD in sociology (her thesis focuses on a very specialised aspect of buisness training) and while observing and helping with some of the work I can confirm that sociology is very much a real science. Especially where data analysis is concerned.

Most of the sciences explain the 'how' where sociology tends to focus more on the 'why' (massive generalisation alert!) which is arguably more important and useful depending on what you're looking at.

 

[CnoEvil]

I like to keep it fairly simple ie.

- Competence of the power supply ie. Look at the power into 8 Ohms and 4 Ohms, and if it gets close to doubling, that is a good sign.

- Speaker sensitivity is key to getting volume.

- Speakers with plummeting impedance need amps with robust power supplies.

- Watts are certainly important, but as been said above, it is not the full story. The interaction between amp/speakers is what really counts. A handful of Watts can sound amazingly loud through very sensitive speakers.

+1

There I go agreeing with you again. *shok*

Now it's my turn for a little lie down. *scratch_one-s_head*