Bi Amp & Bi Wire Question

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Discussion

Andy JB

Original Poster:

1,319 posts

218 months

Tuesday 15th September 2015
quotequote all
I'm beginning to upgrade some of my source components eg Roksan K3 CD & Pro-Ject Turntable. Consequently the amps are next in line for review although i do actually enjoy their neutral sound delivery when partnered with a pair of floor standing Ruark Tallisman 2's, its very impressive on all levels in a medium sized room.

Now to the question - my aging Arcam amps are rated at 50w per channel which I have bi-wired and bi-amped ie power amplifier driving bass cones & pre amp powering the tweeters. Does the fact that its bi-amped increase the power rating feed to 100watts due to the two amps, or does it not work like that? My speakers recommend no higher than 100w to drive them so there will either be some room for improvement or I'm already at my max?

I was looking perhaps at something like the Linn LK140 power & Linn Kolektor pre amp rated at 95w per channel into 8ohm speakers as a potential upgrade, by increasing the available power without distortion or clipping at higher listening levels and smoothing things out overall with the new components. Any insights helpful

Crackie

6,386 posts

241 months

Tuesday 15th September 2015
quotequote all
Andy JB said:
Now to the question - my aging Arcam amps are rated at 50w per channel which I have bi-wired and bi-amped ie power amplifier driving bass cones & pre amp powering the tweeters. Does the fact that its bi-amped increase the power rating feed to 100watts due to the two amps, or does it not work like that? My speakers recommend no higher than 100w to drive them so there will either be some room for improvement or I'm already at my max?

I was looking perhaps at something like the Linn LK140 power & Linn Kolektor pre amp rated at 95w per channel into 8ohm speakers as a potential upgrade, by increasing the available power without distortion or clipping at higher listening levels and smoothing things out overall with the new components. Any insights helpful
The Arcams currently deliver 50watts to the LF and HF sections of your speakers but the power amp is only delivering current at low frequencies and the integrated amp is only delivering current at higher frequencies. Their contribution is shared rather than combined.

100watt amps will play louder but only 3dB louder which isn't much. Do you currently feel the need to play the Arcams with the volume maxed ?

jamesh764

184 posts

141 months

Tuesday 15th September 2015
quotequote all
The Linn Kolektor is just a pre-amp, so if you wanted to bi-amp you would need two LK140s.

It sounds as though you are using an Arcam integrated amplifier plus a power amplifier. If each amp is rated at 50 watts per channel, and you have two amps driving each speaker, then yes, the total power being sent to each speaker will be 100 watts.

Under driving a speaker, i.e. running a lower powered amp flat out is far more likely to damage it than running a higher powered amp.


Crackie

6,386 posts

241 months

Tuesday 15th September 2015
quotequote all
jamesh764 said:
The Linn Kolektor is just a pre-amp, so if you wanted to bi-amp you would need two LK140s.

It sounds as though you are using an Arcam integrated amplifier plus a power amplifier. If each amp is rated at 50 watts per channel, and you have two amps driving each speaker, then yes, the total power being sent to each speaker will be 100 watts.

Under driving a speaker, i.e. running a lower powered amp flat out is far more likely to damage it than running a higher powered amp.
There won't be 100watts delivered to each speaker; the system does not play any louder when bi-wired or bi-amped. There is no increase in power supply voltage inside the amps and the gain of each amp does not change.
The power amp will deliver approx. 25W to the bass driver from 0Hz the speaker crossover frequency at about 2500Hz; the integrated amp will be delivering approx. 25W to the tweeter for frequencies above 2500Hz.

Agree with your comment about running a lower powered amp flat out being likely to cause damage.

Edited by Crackie on Tuesday 15th September 22:14

Andy JB

Original Poster:

1,319 posts

218 months

Wednesday 16th September 2015
quotequote all
Crackie said:
100watt amps will play louder but only 3dB louder which isn't much. Do you currently feel the need to play the Arcams with the volume maxed ?
No I don't play the Arcam maxed out and they cope very well at reasonably high volumes & I enjoy their sound - perhaps I may leave well alone they seem well built & no reliability issues to date. I guess I was hoping by changing the amps for something more powerful it would reveal more or compliment my new source components without maxing out the existing amp/speakers especially if the amp was operating at its limit. I do understand the points made about marginal increase in db compared to much higher power feeds.

varsas

4,004 posts

201 months

Wednesday 16th September 2015
quotequote all
Hi. Some observations.

First, don't make the mistake of equating power with quality. The amp making 120w is not neccesearily better than the one making 100w, that would be a bit like saying a Jaguar S-type drives better than a Lotus Elise because it has more power, it doesn't always work like that.

Second, don't make the mistake of thinking the 120w amplifier is actually more powerful than the 100w one. There is no set way to measure power, and some manufacturers are more realistic than others. Is that 120w still produced when running more than one channel, over a wide frequency range and into a varying load?

Third, you do need enough power (as others have said) but how much is enough? Well, lets say you listen at 2 meters from your speakers at 90db. 90 db is very loud by the way, I wouldn't ever listen at that level. It turns out you'd need less than 5 watts for that. Amazing, hu? But you know speakers have a sensitivity on them? About 90 db/w/m, right? That means if you feed in 1 watt, and sit 1 meter away you'll get 90db of sound. Now you need a bit more than 5 watts; the real resistence of the speaker will go down, probably to around half of what's printed, in actual use, meaning your amp will have to work harder, you have two channels to drive etc but I'm just trying to re-calibrate you understanding of amplifier power levels a bit. A real 25 watts is actually very powerful.

My advice would be to listen to a few amplifiers around your chosent budget, and one for half the price just to see what the difference is. Unless you live in a nightclub or have very hard-to-drive speakers don't worry about the power, just buy the one you like best.

Edited by varsas on Wednesday 16th September 10:49

ian996

837 posts

110 months

Wednesday 16th September 2015
quotequote all
Just to play devil's advocate - while I'd agree with Varsus that it is surprising how much volume can be generated by very few watts, it's possibly even more surprising how many watts are required to cleanly generate dynamic peaks on speakers with average efficiency. Strangely, this means you can play at uncomfortable levels with 50 watts listening to highly compressed rock music, but you may genuinely need several hundred watts to fulfill the demands of a piece of acoustic music played at "loud" but by no means offensive volumes. (It's also worth mentioning that your speakers' maximum 100w capacity is their sustained capacity - they can cope with very short peaks at much higher levels.)

In practice, all else being equal (which it normally isn't), an increase from 50wpc (whether single or bi-amped) to 100wpc, could lead to an improved sense of dynamics and a less edgy sound at higher volume.


The most reliable way of assessing whether a prospective upgrade is going to provide what you are looking for is to have a prolonged audition in your own system. Quite a few dealers now offer this, but (quite understandably) you normally end up paying top wack for the privilege. A more risky approach is to take a punt on a second hand item based on reputation, on the basis that you should be able to sell it on again at a fairly minimal loss if it doesn't work out. Personally, I'd rather take that second option than a standard audition at a dealers, which won't tell you what a unit will sound like in your system.


red997

1,304 posts

208 months

Wednesday 16th September 2015
quotequote all
some interesting comments on power & speakers;

1 W of power is 1 W. no such thing as 'real' watts
that is 1W RMS; and it's quoted into an impedance - 8ohms, 6 ohms, 4 ohms etc
not peak, not peak to peak etc etc

sensitivities of speakers are expressed in dB @ 1W RMS

I do agree about power ratings on amplifiers being misleading.
example:
I've seen / measured amps that state 100WRMS into 8ohms.
that fact is measured to be true - for about 2 seconds.
The Amp Power supply is giving way at full load; it' settled on about 80W RMS continuous
A well designed amp (like the Linn you mention) will provide it's RMS power continuously.

A good rule of thumb for amplifiers is to look at how they deliver the watts into varying impedance loads.
i.e.
50W into 8 ohms
100W into 4 Ohms
200W into 2 ohms
This would be an amplifier with a very well designed output circuit and an excellent power supply
This usually translates into a very dynamic sound.
Bi amping usually requires an active crossover, and multiple power amps
bi wiring basically just uses a bit more wire to separate the crossover components in the speaker from each other.
I personally can't tell hardly any difference in bi wiring (but then I only have a pair of Soundcraft studio monitors to test this on)
Bi amping done properly can be like night and day.
I currently have a Linn Isobarik system that is actively powered;
Six power amps per side, fed by a digital crossover, which is fed digitally from an RTA, optical in from my Macbook or CD player
This does sound breathtaking - to me.
I've heard them side by side a pair of current Linn Klimax, and preferred mine. Though the Klimax philosophy is the same as my setup

Not sure if this all helps but hopefully provides some food for thought.

David
(back to designing amplifiers now...)



P700DEE

1,107 posts

229 months

Wednesday 16th September 2015
quotequote all
The power amplifier output wattage is almost useless as a measure of quality and volume achieveable. Just like in cars a bigger engine (higher watage) should give a better output and ultimately higher top speed (Maximum volume)but not necessarily the acceleration and dynamics (timing , speed of attack etc.)
In a car a bigger engine should mean more power (watts)but does not mean that it will handle well (give a good reproduction of the music).

A 1 watt amp is normally enough for most listening , if you have speakers of 89dB efficiency at 1 watt you get enough for much of your listening. Having a bigger capability should also translate to better dynamics because the amp is well within it's operating parameters but amp manufacturers have used the wattage as a sales tool for so long that we all fall into the trap. In general you need to go for ten times the power to double the loudness so a change from 50 to 100 watts wil not make much difference. Bi Amping works because the amp has less to drive and more capacity to drive it. When buying Hi-Fi there is no substitute for a decent test drive wink

Super Slo Mo

5,368 posts

197 months

Wednesday 16th September 2015
quotequote all
Crackie said:
100watt amps will play louder but only 3dB louder which isn't much. Do you currently feel the need to play the Arcams with the volume maxed ?
3dB increase is a doubling of the level. That's quite a lot isn't it? Admittedly the way we perceive the increase in level isn't quite so straightforward but nevertheless it's not insignificant whichever way you look at it.

Crackie

6,386 posts

241 months

Wednesday 16th September 2015
quotequote all
Super Slo Mo said:
Crackie said:
100watt amps will play louder but only 3dB louder which isn't much. Do you currently feel the need to play the Arcams with the volume maxed ?
3dB increase is a doubling of the level. That's quite a lot isn't it? Admittedly the way we perceive the increase in level isn't quite so straightforward but nevertheless it's not insignificant whichever way you look at it.
The Ruarks are rated at 88db so will generate 105dB at 1m with a 50w (17dbw ) amp. This will be 108db for a pair at 1m, 102dB at 2m and 99dB at a realistic 3m listening distance. As P700DEE posted above, to perceive double that at the same listening position, if the Ruarks could handle it, it would require a 400-500watt amp.

- Doubling of perceived loudness is usually considered to be between +9dB and +10dB. The figure appears to be vague but as you say perceived loudness isn't straightforward to define. It is a subjective measurement and varies depending on the listener; it cannot be as easily defined as SPL, power or voltage. Perceived loudness is not the same thing as sound pressure level.
- A doubling of sound pressure level equates to +6dB spl,
- Doubling of power level in watts equates to +3dB. The unit of measurement is dBw,
- Doubling an electric voltage level equates to +6dB. The unit of measurement is dBv.

Edited by Crackie on Saturday 19th September 23:56

Crackie

6,386 posts

241 months

Friday 18th September 2015
quotequote all
Andy JB said:
Crackie said:
100watt amps will play louder but only 3dB louder which isn't much. Do you currently feel the need to play the Arcams with the volume maxed ?
No I don't play the Arcam maxed out and they cope very well at reasonably high volumes & I enjoy their sound - perhaps I may leave well alone they seem well built & no reliability issues to date. I guess I was hoping by changing the amps for something more powerful it would reveal more or compliment my new source components without maxing out the existing amp/speakers especially if the amp was operating at its limit. I do understand the points made about marginal increase in db compared to much higher power feeds.
Sorry for going off on a tangent Andy............

I always advocate listening rather than reading reviews but I'm not sure where you get to audition Temple Audio's products.

Their amps have been causing quite a stir on various audio forums and in specialist hi-fi press for the past couple of years. Cynics might not read the testimonials on the Temple website but they appear genuine to me and the few reviews I've seen are very complementary.

Here are a couple of links
http://www.templeaudio.net/monoblock.html
http://www.enjoythemusic.com/magazine/equipment/05...

Good luck


Edited by Crackie on Tuesday 22 September 21:38

Monty Python

4,812 posts

196 months

Tuesday 22nd September 2015
quotequote all
Can you power tweeters from a pre-amp? I was always under the impression that biamping required two power amps per channel, one for low and one for high frequencies.

Red 5

1,021 posts

179 months

Wednesday 30th September 2015
quotequote all
Monty Python said:
Can you power tweeters from a pre-amp? I was always under the impression that biamping required two power amps per channel, one for low and one for high frequencies.
No you can't, but the OP uses confused terms, people get confused, then other go off topic. Normal forum life :-)


The OP does not have a separate pre-amp and is not "Bi-Wiring" anything.

He has an integrated amp (containing a pre and power section) single wired to the treble of each speaker. This is delivering 50wpc to the HF of each speaker from a single chassis with its own power supply.

He then has a seperate power amp single wired to the LF part of each speaker. This is also delivering 50wpc from the seperate chassis and power supply.

The signals from each amp are exactly the same! There are no electronic X-overs in the Arcam bits!
The amps feed 4 X 50wpc into the speakers and the speaker passive X-over has to sort it out.

Some confusion arises due to the OP possibly buying "Bi-Wire'" speaker cable to achieve the above. He needed 4 cores to each speaker. This is not "Bi-Wired" but 2 X single wired, or Bi-Amped.

The rating on the speakers is 100wpc yes? Those are measured as clean watts though, so normally, an amp of 500wpc (or more) would be needed to deliver a perfectly clean 100wpc!

It is correctly stated above, that not all 50wpc amps are the same power. Far from it sadly, but that's not going to change!

The main issue for home use is dynamic range. Two identical systems playing at exactly the same volume can sound very different if one has a much more powerful amp.
The speakers and spl are can be the same, but one will effortlessly achieve a wider range of sounds, more separated and less muddled.

The number of quoted watts is not however the barometer of amp power. Sadly there is no standardised way to measure!




Red 5

1,021 posts

179 months

Wednesday 30th September 2015
quotequote all
Andy JB said:
I'm beginning to upgrade some of my source components eg Roksan K3 CD & Pro-Ject Turntable. Consequently the amps are next in line for review although i do actually enjoy their neutral sound delivery when partnered with a pair of floor standing Ruark Tallisman 2's, its very impressive on all levels in a medium sized room.

Now to the question - my aging Arcam amps are rated at 50w per channel which I have bi-wired and bi-amped ie power amplifier driving bass cones & pre amp powering the tweeters. Does the fact that its bi-amped increase the power rating feed to 100watts due to the two amps, or does it not work like that? My speakers recommend no higher than 100w to drive them so there will either be some room for improvement or I'm already at my max?

I was looking perhaps at something like the Linn LK140 power & Linn Kolektor pre amp rated at 95w per channel into 8ohm speakers as a potential upgrade, by increasing the available power without distortion or clipping at higher listening levels and smoothing things out overall with the new components. Any insights helpful
Andy,
If you try some Linn or Naim kit of a similar quoted power to your combined Arcam bits, you'll achieve a wider dynamic range, without having to turn the volume up more. However, if you do, things will stay composed for longer.
Separating the pre-amp from the power amps will be a big part of this improved focus and improved image.

The continuous output of the 100wpc Linn / Naim, could be double that of the 100wpc Arcam bits!

Crackie

6,386 posts

241 months

Thursday 1st October 2015
quotequote all
Red 5 said:
Sadly there is no standardised way to measure!
http://www.iec.ch/

https://en.wikipedia.org/wiki/List_of_IEC_standard... IEC268 is the standard for sound system equipment.

https://en.wikipedia.org/wiki/Institute_of_Electri...

https://en.wikipedia.org/wiki/American_National_St...





Edited by Crackie on Friday 2nd October 11:11

Red 5

1,021 posts

179 months

Friday 2nd October 2015
quotequote all
P
Crackie said:
My apologies!

I should have said, there is no widely adhered to method for consumer electronics.

So you end up with 50wpc amps on sale in micro systems priced at £199, then huge power amplifiers with massive price tags, also with 50wpc, but many magnitudes more powerful than afore mentioned micro. It's a shambles that confuses customers :-(
It's not a suitable way of establishing anything tangible!

We then get the "How many watts are those speakers" question, thinking that any quoted number will tell them how loud the speakers will go :-(




Edited by Red 5 on Saturday 3rd October 20:32

StuntmanMike

11,671 posts

150 months

Saturday 3rd October 2015
quotequote all
red997 said:
some interesting comments on power & speakers;

1 W of power is 1 W. no such thing as 'real' watts
that is 1W RMS; and it's quoted into an impedance - 8ohms, 6 ohms, 4 ohms etc
not peak, not peak to peak etc etc

sensitivities of speakers are expressed in dB @ 1W RMS

I do agree about power ratings on amplifiers being misleading.
example:
I've seen / measured amps that state 100WRMS into 8ohms.
that fact is measured to be true - for about 2 seconds.
The Amp Power supply is giving way at full load; it' settled on about 80W RMS continuous
A well designed amp (like the Linn you mention) will provide it's RMS power continuously.

A good rule of thumb for amplifiers is to look at how they deliver the watts into varying impedance loads.
i.e.
50W into 8 ohms
100W into 4 Ohms
200W into 2 ohms
This would be an amplifier with a very well designed output circuit and an excellent power supply
This usually translates into a very dynamic sound.
Bi amping usually requires an active crossover, and multiple power amps
bi wiring basically just uses a bit more wire to separate the crossover components in the speaker from each other.
I personally can't tell hardly any difference in bi wiring (but then I only have a pair of Soundcraft studio monitors to test this on)
Bi amping done properly can be like night and day.
I currently have a Linn Isobarik system that is actively powered;
Six power amps per side, fed by a digital crossover, which is fed digitally from an RTA, optical in from my Macbook or CD player
This does sound breathtaking - to me.
I've heard them side by side a pair of current Linn Klimax, and preferred mine. Though the Klimax philosophy is the same as my setup

Not sure if this all helps but hopefully provides some food for thought.

David
(back to designing amplifiers now...)
OK good explanation, how ( if you were me ) would you wire your speakers?, I have Arcam Delta 290 pre/power amps and B&W 603 s3 speakers.

Red 5

1,021 posts

179 months

Saturday 3rd October 2015
quotequote all
StuntmanMike said:
red997 said:
some interesting comments on power & speakers;

1 W of power is 1 W. no such thing as 'real' watts
that is 1W RMS; and it's quoted into an impedance - 8ohms, 6 ohms, 4 ohms etc
not peak, not peak to peak etc etc

sensitivities of speakers are expressed in dB @ 1W RMS

I do agree about power ratings on amplifiers being misleading.
example:
I've seen / measured amps that state 100WRMS into 8ohms.
that fact is measured to be true - for about 2 seconds.
The Amp Power supply is giving way at full load; it' settled on about 80W RMS continuous
A well designed amp (like the Linn you mention) will provide it's RMS power continuously.

A good rule of thumb for amplifiers is to look at how they deliver the watts into varying impedance loads.
i.e.
50W into 8 ohms
100W into 4 Ohms
200W into 2 ohms
This would be an amplifier with a very well designed output circuit and an excellent power supply
This usually translates into a very dynamic sound.
Bi amping usually requires an active crossover, and multiple power amps
bi wiring basically just uses a bit more wire to separate the crossover components in the speaker from each other.
I personally can't tell hardly any difference in bi wiring (but then I only have a pair of Soundcraft studio monitors to test this on)
Bi amping done properly can be like night and day.
I currently have a Linn Isobarik system that is actively powered;
Six power amps per side, fed by a digital crossover, which is fed digitally from an RTA, optical in from my Macbook or CD player
This does sound breathtaking - to me.
I've heard them side by side a pair of current Linn Klimax, and preferred mine. Though the Klimax philosophy is the same as my setup

Not sure if this all helps but hopefully provides some food for thought.

David
(back to designing amplifiers now...)
OK good explanation, how ( if you were me ) would you wire your speakers?, I have Arcam Delta 290 pre/power amps and B&W 603 s3 speakers.
You only have one amp (I think, as you use a plural, not a number) so wire that to the speakers with some decent speaker cable. If you buy another power amp, remove the bridges on the speaker X-overs and run another set of wires.

StuntmanMike

11,671 posts

150 months

Saturday 3rd October 2015
quotequote all
Red 5 said:
StuntmanMike said:
red997 said:
some interesting comments on power & speakers;

1 W of power is 1 W. no such thing as 'real' watts
that is 1W RMS; and it's quoted into an impedance - 8ohms, 6 ohms, 4 ohms etc
not peak, not peak to peak etc etc

sensitivities of speakers are expressed in dB @ 1W RMS

I do agree about power ratings on amplifiers being misleading.
example:
I've seen / measured amps that state 100WRMS into 8ohms.
that fact is measured to be true - for about 2 seconds.
The Amp Power supply is giving way at full load; it' settled on about 80W RMS continuous
A well designed amp (like the Linn you mention) will provide it's RMS power continuously.

A good rule of thumb for amplifiers is to look at how they deliver the watts into varying impedance loads.
i.e.
50W into 8 ohms
100W into 4 Ohms
200W into 2 ohms
This would be an amplifier with a very well designed output circuit and an excellent power supply
This usually translates into a very dynamic sound.
Bi amping usually requires an active crossover, and multiple power amps
bi wiring basically just uses a bit more wire to separate the crossover components in the speaker from each other.
I personally can't tell hardly any difference in bi wiring (but then I only have a pair of Soundcraft studio monitors to test this on)
Bi amping done properly can be like night and day.
I currently have a Linn Isobarik system that is actively powered;
Six power amps per side, fed by a digital crossover, which is fed digitally from an RTA, optical in from my Macbook or CD player
This does sound breathtaking - to me.
I've heard them side by side a pair of current Linn Klimax, and preferred mine. Though the Klimax philosophy is the same as my setup

Not sure if this all helps but hopefully provides some food for thought.

David
(back to designing amplifiers now...)
OK good explanation, how ( if you were me ) would you wire your speakers?, I have Arcam Delta 290 pre/power amps and B&W 603 s3 speakers.
You only have one amp (I think, as you use a plural, not a number) so wire that to the speakers with some decent speaker cable. If you buy another power amp, remove the bridges on the speaker X-overs and run another set of wires.
Yes your right, this comes from drinking on a empty head.
I have a Delta 290 integrated amp and a Delta 290 power amp, If I am understanding this thread correctly to truly bi amp I would have to have two 290 power amps?