Shame AVI nobbled their Lab series of amps

[Infiniteloop]

Seems ok to me.

For the last 10 years AVI have sold everything they've been able to make with orders exceeding production capacity at times. No debts and oodles of cash in the bank.

Hardly a failing strategy when compared against the traditional HiFi market. Naim had to be sold off to Focal to enable Paul Stevenson's pension to be paid.

JC

I'm not knocking their sales or their admirable bank account. Well done!

Just not accepting that AVI have re-invented the future of home audio, or represent anything but a small, elite (and rather traditional) British hi-fi brand despite it's claims otherwise.

In the real world Chebby, our products are very high end. I think there might be a breakdown of what sells and for what price on the WHF website. It's surprisingly inexpensive.

There is no future for home audio beyond inexpensive docks IMO, but there is for music collectors and professionals associated with the recording and production of music, film and broadcast. For example we've just sold, via our Indian agents, to a top Bollywood sound man and we already have BBC types and others around the world, even NZ radio OB.

"very high end". - Really?

Your products may sound great to some ears (I haven't heard them yet but am looking to put that right) but in reality they consist of a traditional wooden box which contains a couple of sourced drivers, some electronics and a digital Amp. - Not too far from what most dad's had.

Of course it's great that your company is making money, that's what companies are for, but how about putting some of that money to use by innovating?

If you want to know what real innovation looks like, take a look at what Devialet are doing with their Phantom range.

 

[chebby]

I think you've just been Trumped, chebby ;-)

Indeed.

 

[Ashley James]

Seems ok to me.

For the last 10 years AVI have sold everything they've been able to make with orders exceeding production capacity at times. No debts and oodles of cash in the bank.

Hardly a failing strategy when compared against the traditional HiFi market. Naim had to be sold off to Focal to enable Paul Stevenson's pension to be paid.

JC

I'm not knocking their sales or their admirable bank account. Well done!

Just not accepting that AVI have re-invented the future of home audio, or represent anything but a small, elite (and rather traditional) British hi-fi brand despite it's claims otherwise.

In the real world Chebby, our products are very high end. I think there might be a breakdown of what sells and for what price on the WHF website. It's surprisingly inexpensive.

There is no future for home audio beyond inexpensive docks IMO, but there is for music collectors and professionals associated with the recording and production of music, film and broadcast. For example we've just sold, via our Indian agents, to a top Bollywood sound man and we already have BBC types and others around the world, even NZ radio OB.

"very high end". - Really?

Your products may sound great to some ears (I haven't heard them yet but am looking to put that right) but in reality they consist of a traditional wooden box which contains a couple of sourced drivers, some electronics and a digital Amp. - Not too far from what most dad's had.

Of course it's great that your company is making money, that's what companies are for, but how about putting some of that money to use by innovating?

If you want to know what real innovation looks like, take a look at what Devialet are doing with their Phantom range.

If £3-500 is the typical household spend on speakers/AV/Media then those spending £700 or £1500 are likely to be in a high income group. 6% of Gloucestershire has an income of £70,000 a year or more.

Depends what you call innovation and whose speakers sound best. SQ is where we're best and for good reason. Sinar Baja are world leaders and if you saw earlier posts, you'll know about them and their view of us. However this type of discussion belongs on the AVI forum, not on WHF's.

What I can say is that there's very little new under the sun and most of what you read (except from me) is from very skilled ad copy writers, so may not be innovation at all, just whatever they've done to meet their criteria written up to excite the target group.

Audio is a mature technology, DACs and Amps both have far lower distortion than you can hear, which just leaves the weakest link as speaker drivers and passive crossovers. These are where the progress is needed and there's a long way to go with speakers. Active crossovers can be inaudible.

Part of the reason for the success of headphones, apart from convenience, is that they have far less distortion than speakers.

1. They're really just a small single driver, so no crossover, full range and effectively active. As long as the diaphragm doesn't exceed 40mm or thereabouts, breakup is outside the audible range. Sennheiser HD800s are 52mm ring radiators, so basically two drivers, a much bigger radiating area and less distortion.

2. You're very close to the diaphragms, which means they don't have to move far to make lots of noise, so there is far less distortion.

 

[shadders]

1. Because the Amp comes after the crossover, it is connected directly to its driver and can control it better. Typically about 300 times better. This is a proven fact.

Hi

Can you provide the basis for the 300x better specification you have stated, such as, is this 300x less THD at a specific frequency, and if so, what was the frequency used?

Thanks and regards,

Shadders.

 

[Ashley James]

1. Because the Amp comes after the crossover, it is connected directly to its driver and can control it better. Typically about 300 times better. This is a proven fact.

Hi

Can you provide the basis for the 300x better specification you have stated, such as, is this 300x less THD at a specific frequency, and if so, what was the frequency used?

Thanks and regards,

Shadders.

Yes of course, but you only have to listen and it's obvious. As everyone says who's heard them, actives are astonishingly clear, even at much higher volumes than ordinary speakers.

Your post shows how daft internet arguments are. If you think the claims are reckless or exaggerated, go and listen or just ignore them and carry on

PS. It's the damping factor that's 300 times better because the crossover isn't able to disconnect drivers from amps as happens in old passives

 

[shadders]

1. Because the Amp comes after the crossover, it is connected directly to its driver and can control it better. Typically about 300 times better. This is a proven fact.

Hi

Can you provide the basis for the 300x better specification you have stated, such as, is this 300x less THD at a specific frequency, and if so, what was the frequency used?

Thanks and regards,

Shadders.

Yes of course, but you only have to listen and it's obvious. As everyone says who's heard them, actives are astonishingly clear, even at much higher volumes than ordinary speakers.

Your post shows how daft internet arguments are. If you think the claims are reckless or exaggerated, go and listen or just ignore them and carry on

PS. It's the damping factor that's 300 times better because the crossover isn't able to disconnect drivers from amps as happens in old passives

Hi,

Ok, Thanks. We do not seem to have an objective metric to equate damping factor to sound quality. I suppose the bigger the number the better.

AVI could provide THD figures as per Hifi News reviews, to see the relative gains of using active speakers against passive alternatives.

Regards,

Shadders.

 

[Ashley James]

1. Because the Amp comes after the crossover, it is connected directly to its driver and can control it better. Typically about 300 times better. This is a proven fact.

Hi

Can you provide the basis for the 300x better specification you have stated, such as, is this 300x less THD at a specific frequency, and if so, what was the frequency used?

Thanks and regards,

Shadders.

Yes of course, but you only have to listen and it's obvious. As everyone says who's heard them, actives are astonishingly clear, even at much higher volumes than ordinary speakers.

Your post shows how daft internet arguments are. If you think the claims are reckless or exaggerated, go and listen or just ignore them and carry on

PS. It's the damping factor that's 300 times better because the crossover isn't able to disconnect drivers from amps as happens in old passives

Hi,

Ok, Thanks. We do not seem to have an objective metric to equate damping factor to sound quality. I suppose the bigger the number the better.

AVI could provide THD figures as per Hifi News reviews, to see the relative gains of using active speakers against passive alternatives.

Regards,

Shadders.

We did some for one of the forums once and they argued, so instead we compared the distortion in a 3p op-amp for an active crossover with inductors in a passive one. Martin wrote up all his measurements and they're in the reference section of our Forum. A cheap op-amp has about 0.002% THD, no inductors are used in active crossovers and they can have between 1 & 20% THD in a passive one depending on amplitude level.

THD measurements of active speakers are better than passives, but because the drivers are the limiting factor, they have high levels of benign harmonic distortion, you don't see the problems from passive crossovers. They're terrible things really and IMO it's only because of an accident of history that they survived in Hifi but not Cinemas, Pro Audio monitoring or PA, where they swept in during the seventies when op-amps appeared.

Why not go and audition a pair of £250 Active Yamahas, I promise you a shock. Then imagine what a serious design with the very best bits might be like.

 

[shadders]

Hi Ashley,

I can see that inductors may introduce harmonic distortion, but lastest designs of passive speakers show THD to be 0.1% to 0.5%. This is from Hifi News - quick scan of some speakers reviewed - and at low volume levels.

If amplifiers can sound different with the same set of speakers, and people agree that this is the case, then perhaps any active design is restricted by the amplifier and drive units used. Perhaps some of the gains of active speakers are negated by choice of drive units and amplifier topology ?, as some people prefer class A/B to D, to A etc.,

Regards,

Shadders.

 

[tonky]

Hi there,

I've googled around looking for the pair of yamaha actives but can't find them. Is it possible to give a model number for the pair nd any uk stockists? (east midlands area)

cheers tonky

 

[Ashley James]

Hi Ashley,

I can see that inductors may introduce harmonic distortion, but lastest designs of passive speakers show THD to be 0.1% to 0.5%. This is from Hifi News - quick scan of some speakers reviewed - and at low volume levels.

If amplifiers can sound different with the same set of speakers, and people agree that this is the case, then perhaps any actice design is restricted by the amplifier and drive units used. Perhaps some of the gains of active speakers are negated by choice of drive units and amplifier topology ?, as some people prefer class A/B to D, to A etc.,

Regards,

Shadders.

Forget THD in speakers for the reasons I've given. Forget differences between competent amps, they dont exist in properly conducted tests.

The really big difference in sound quality between passives and competent actives is because the drivers more faithfully follow amp's instructions. There isn't a passive crossover to disconnect it and give up to 1/300th of the control.

The other monster difference is that actives have steeper filters and with 8th order ones as we use you cannot hear the crossover region nor an unhappy tweeter for as much as two octaves below the intersection point as you get with low order filters.

This is why active owners won't go back to passives. They boom, they Tizz, they lack dynamics and they congest in comparison.

I posted what Sinar Baja said about ours. It's a huge difference.

Trouble is that there have been some unconvincing actives sold for hi fi over the years, so understandably punters are suspicious.

 

[richardw42]

Look for the HS series (HS7 etc)

 

[Ashley James]

Hi there,

I've googled around looking for the pair of yamaha actives but can't find them. Is it possible to give a model number for the pair nd any uk stockists? (east midlands area)

cheers tonky

i think they're called HS50s and you'll need to look at the Sound On Sound website for pro audio dealers.

 

[steve_1979]

Hi there,

I've googled around looking for the pair of yamaha actives but can't find them. Is it possible to give a model number for the pair nd any uk stockists? (east midlands area)

cheers tonky

Search for your nearest pro-audio store and give them a call to see if they have any in stock (or ask if they know anyone else who does stock them). Yamaha monitors are very popular so it shouldn't be hard to find one.

 

[steve_1979]

i think they're called HS50s and you'll need to look at the Sound On Sound website for pro audio dealers.

The HS50M was the older version which was discontinued a couple of years ago. Yamaha have now brought out a slightly modified Mk2 version called the HS5.

There are three different sizes of the Yamaha HS speakers.

The HS5 is the 5.25" woofer model.

The HS7 is the 6.5" woofer model.

The HS8 is the 8" woofer model.

 

[Infiniteloop]

Hi Ashley,

I can see that inductors may introduce harmonic distortion, but lastest designs of passive speakers show THD to be 0.1% to 0.5%. This is from Hifi News - quick scan of some speakers reviewed - and at low volume levels.

If amplifiers can sound different with the same set of speakers, and people agree that this is the case, then perhaps any actice design is restricted by the amplifier and drive units used. Perhaps some of the gains of active speakers are negated by choice of drive units and amplifier topology ?, as some people prefer class A/B to D, to A etc.,

Regards,

Shadders.

Forget THD in speakers for the reasons I've given. Forget differences between competent amps, they dont exist in properly conducted tests.

The really big difference in sound quality between passives and competent actives is because the drivers more faithfully follow amp's instructions. There isn't a passive crossover to disconnect it and give up to 1/300th of the control.

The other monster difference is that actives have steeper filters and with 8th order ones as we use you cannot hear the crossover region nor an unhappy tweeter for as much as two octaves below the intersection point as you get with low order filters.

This is why active owners won't go back to passives. They boom, they Tizz, they lack dynamics and they congest in comparison.

I posted what Sinar Baja said about ours. It's a huge difference.

Trouble is that there have been some unconvincing actives sold for hi fi over the years, so understandably punters are suspicious.

You might find this educational:

http://en.devialet.com/expertpro/#technologies/exclusive/sam/

 

[Ashley James]

Hi Ashley,

I can see that inductors may introduce harmonic distortion, but lastest designs of passive speakers show THD to be 0.1% to 0.5%. This is from Hifi News - quick scan of some speakers reviewed - and at low volume levels.

If amplifiers can sound different with the same set of speakers, and people agree that this is the case, then perhaps any actice design is restricted by the amplifier and drive units used. Perhaps some of the gains of active speakers are negated by choice of drive units and amplifier topology ?, as some people prefer class A/B to D, to A etc.,

Regards,

Shadders.

Forget THD in speakers for the reasons I've given. Forget differences between competent amps, they dont exist in properly conducted tests.

The really big difference in sound quality between passives and competent actives is because the drivers more faithfully follow amp's instructions. There isn't a passive crossover to disconnect it and give up to 1/300th of the control.

The other monster difference is that actives have steeper filters and with 8th order ones as we use you cannot hear the crossover region nor an unhappy tweeter for as much as two octaves below the intersection point as you get with low order filters.

This is why active owners won't go back to passives. They boom, they Tizz, they lack dynamics and they congest in comparison.

I posted what Sinar Baja said about ours. It's a huge difference.

Trouble is that there have been some unconvincing actives sold for hi fi over the years, so understandably punters are suspicious.

You might find this educational:

http://en.devialet.com/expertpro/#technologies/exclusive/sam/

Have a look at the way the more expensive Yamaha AV Amp/processors manage their amplifiers and the loads they see.

Not to take anything away from what I'm sure is an excellent stand alone amp, but there's nothing new under the sun and this isn't needed in active speakers.

Have you read about the DAC/Audio chips they use in phones? You'd be amazed at how clever they are.

 

[shadders]

1. Because the Amp comes after the crossover, it is connected directly to its driver and can control it better. Typically about 300 times better. This is a proven fact.

Hi

Can you provide the basis for the 300x better specification you have stated, such as, is this 300x less THD at a specific frequency, and if so, what was the frequency used?

Thanks and regards,

Shadders.

Yes of course, but you only have to listen and it's obvious. As everyone says who's heard them, actives are astonishingly clear, even at much higher volumes than ordinary speakers.

Your post shows how daft internet arguments are. If you think the claims are reckless or exaggerated, go and listen or just ignore them and carry on

PS. It's the damping factor that's 300 times better because the crossover isn't able to disconnect drivers from amps as happens in old passives

Hi,

I was mulling over the 300x better damping factor, and I am not sure this is an accurate statement.

A passive filter should present negligible impedance at the passband frequency, or depending on the application, impedance match.

Damping factor is defined as the load impedance divided by the amplifier output impedance. If the AVI active loudspeakers have a better damping factor by 300x, this infers that a passive filter incurs a 50dB insertion loss. This is not correct.

So what are the conditions for a 300x greater damping factor with regards to active loudspeaker compared to a passive loudspeaker.

Thanks and regards,

Shadders.

 

[Ashley James]

1. Because the Amp comes after the crossover, it is connected directly to its driver and can control it better. Typically about 300 times better. This is a proven fact.

Hi

Can you provide the basis for the 300x better specification you have stated, such as, is this 300x less THD at a specific frequency, and if so, what was the frequency used?

Thanks and regards,

Shadders.

Yes of course, but you only have to listen and it's obvious. As everyone says who's heard them, actives are astonishingly clear, even at much higher volumes than ordinary speakers.

Your post shows how daft internet arguments are. If you think the claims are reckless or exaggerated, go and listen or just ignore them and carry on

PS. It's the damping factor that's 300 times better because the crossover isn't able to disconnect drivers from amps as happens in old passives

Hi,

I was mulling over the 300x better damping factor, and I am not sure this is an accurate statement.

A passive filter should present negligible impedance at the passband frequency, or depending on the application, impedance match.

Damping factor is defined as the load impedance divided by the amplifier output impedance. If the AVI active loudspeakers have a better damping factor by 300x, this infers that a passive filter incurs a 50dB insertion loss. This is not correct.

So what are the conditions for a 300x greater damping factor with regards to active loudspeaker compared to a passive loudspeaker.

Thanks and regards,

Shadders.

This was written in March 2009 when the argument was three years old and fifty four years after Wireless World explained the huge advantages of active speakers

Originally posted here,

http://hddaudio.net/bbold/viewtopic.php?pid=6270#p6270
grindrod wrote:
There seem to be some posters that have real trouble accepting the claims made by Ashley I thought I would just post some facts since I actually made the measurements and did the analysis [AVI ADM9]:

Regarding distortion in crossovers:

I measured a typical 2 Way 2nd order LR crossover designed for a crossover frequency of 3.5kHz using a number of different inductors, using the drive units as loads at 10W the electrical harmonic distortion was typically 1% (-40db) for the iron cored inductor samples and 3% (-30dB)for the ferrite cored samples which was a suprise! Measurement frequencies were 1 octave either side of the crossover frequency. I did not use an aircored sample because it was highly resistive (0.8ohms) compared to the drive unit impedance which in itself introduces response anamolies of the order of 10% (-20db) which , since the drive unit signal is in error compared to the input in the passband of the filters,it can legitimately be called distortion. In practice response anomolies are measured with all the inductor types due to their resistance. (This is particularily noticable in 3 way designs where the lower crossover point requires large values of inductance)

By contrast the active filters used in the ADM9s have distortion typically -96dB at the frequencies used above, this means that the active filters in the ADM9s are very much more than 1000 better than the passive crossover.

The mid-band distortion of the ADM9 amplifiers is typically –96dB so even including the amplifier the distortion in the voltage received at the drive units will be better than 50dB lower than a perfect amplifier driving a passive crossover.

Regarding damping factor:

The amplifiers in the ADM9 are optimised for the loads that they see, the output impedance is typically 1mohm mid band, there are two short cables (9”) direct to the drive units.

Now consider a typical passive system, firstly, in order to ensure the amplifier is stable into a wide range of loads it will have some form of output coupling, either a damped inductor or series resistor. Also the typical output imedance is much higher than the ADM9 amplifier since the ADM9 circuit produces an exceptionally low output impedance. Typically the amplifier alone may have an output impedance from 50mohms to 0.5ohms in some cases. Add to that the connector and cable losses, typically 50mohms for 3m of 2.5mm2 cable, and then the crossover losses which may typically be 0.3ohms at DC then the source impedance seen by the bass driver will typically be 0.4ohms to 0.9ohms compared to the couple of milliohms seen by the bass driver in the ADM9.

An important point to make is that in the passive system from a decade either side of the crossover (i.e., 350Hz for the bass driver in the example above) the source impedance rises significantly as the crossover frequency is approached. It is a common mistake to visualise things happening close in around the crossover frequency but in practice things start happening at least a decade away!

I hope this goes some way towards showing that the claims made, not just ADM9s but active speakers in general, are real and factual, correctly designed there are huge advantages in terms of drive unit control and distortion, all this is measurable and is not just ‘an opinion’

I hope this helps in putting this one to bed!

Martin

 

[shadders]

Hi Ashley,

Thanks. I was assuming that the amplifiers had the same output impedance. The external amplifier assumed output impedance may be a bit high, but this will vary with frequency.

Are we assuming that the AVI amplifiers have this low impedance at all frequencies?

Regards,

Shadders.

 

[Infiniteloop]

Hi Ashley,

I can see that inductors may introduce harmonic distortion, but lastest designs of passive speakers show THD to be 0.1% to 0.5%. This is from Hifi News - quick scan of some speakers reviewed - and at low volume levels.

If amplifiers can sound different with the same set of speakers, and people agree that this is the case, then perhaps any actice design is restricted by the amplifier and drive units used. Perhaps some of the gains of active speakers are negated by choice of drive units and amplifier topology ?, as some people prefer class A/B to D, to A etc.,

Regards,

Shadders.

Forget THD in speakers for the reasons I've given. Forget differences between competent amps, they dont exist in properly conducted tests.

The really big difference in sound quality between passives and competent actives is because the drivers more faithfully follow amp's instructions. There isn't a passive crossover to disconnect it and give up to 1/300th of the control.

The other monster difference is that actives have steeper filters and with 8th order ones as we use you cannot hear the crossover region nor an unhappy tweeter for as much as two octaves below the intersection point as you get with low order filters.

This is why active owners won't go back to passives. They boom, they Tizz, they lack dynamics and they congest in comparison.

I posted what Sinar Baja said about ours. It's a huge difference.

Trouble is that there have been some unconvincing actives sold for hi fi over the years, so understandably punters are suspicious.

You might find this educational:

http://en.devialet.com/expertpro/#technologies/exclusive/sam/

Have a look at the way the more expensive Yamaha AV Amp/processors manage their amplifiers and the loads they see.

Not to take anything away from what I'm sure is an excellent stand alone amp, but there's nothing new under the sun and this isn't needed in active speakers.

Have you read about the DAC/Audio chips they use in phones? You'd be amazed at how clever they are.

The point is that SAM adjusts the signal continuously in real time, to the profile of the relevant speaker and this includes the adjustments necessary to overcome the effect of the enclosure on the sound generated. This is something your active speakers cannot do and is something you have clearly missed.

Trust me, - or better still go and hear it for yourself, SAM makes a huge difference to the SQ of the speakers it is profiled to.

You can go further and apply cartridge profiles depending on make and model to the phono section and the Amp has digital tone controls for those instances where room-matching is an issue or a recording isn't as good as it could be.

I think you'll find that this is indeed 'new under the sun'.

Look, I'm sure your products sound fine, but they are clearly not the panacea you are making them out to be.

 

[lpv]

The point is that SAM adjusts the signal continuously in real time, to the profile of the relevant speaker and this includes the adjustments necessary to overcome the effect of the enclosure on the sound generated. This is something your active speakers cannot do and is something you have clearly missed.

Trust me, - or better still go and hear it for yourself, SAM makes a huge difference to the SQ of the speakers it is profiled to.

You can go further and apply cartridge profiles depending on make and model to the phono section and the Amp has digital tone controls for those instances where room-matching is an issue or a recording isn't as good as it could be.

I think you'll find that this is indeed 'new under the sun'.

Look, I'm sure your products sound fine, but they are clearly not the panacea you are making them out to be.

I'm going try that myself very soon...

 

[jcbrum]

Infinite loop wrote "The point is that SAM adjusts the signal"

. . . and therein lies the problem. HiFi is not supposed to "adjust" the signal, it's supposed to reproduce it.

Adjustment is the same as distortion. You might well notice a difference in sound, and you might even like it, but it's still distortion.

Much better to use a system which doesn't "adjust" the signal, but doesn't allow distortion to be introduced.

JC

 

[ID.]

Infinite loop wrote "The point is that SAM adjusts the signal"

. . . and therein lies the problem. HiFi is not supposed to "adjust" the signal, it's supposed to reproduce it.

Adjustment is the same as distortion. You might well notice a difference in sound, and you might even like it, but it's still distortion.

Much better to use a system which doesn't "adjust" the signal, but doesn't allow distortion to be introduced.

JC

Distort the signal to cancel out distortion in the speaker?

The Genelec SAM system works to cancel out room distortions (which is different from the Devialet system which is meant to compensate for shortcomings of speakers). Perhaps that is a situation where I'm prepared to accept that two wrongs (two distortions?) do make a right, because there's no way I'm setting up accoustic panels, etc. in my listening room to make it accoustically inert.

 

[thewinelake.]

Although it'll never be as good as having an acoustically ideal room, I agree that clever manipulation of the audio signal (in EQ and maybe use of delay) may have a place in practical situations. Audyssey seems to "work" for me at making the best of a bad job!

 

[Ashley James]

Although it'll never be as good as having an acoustically ideal room, I agree that clever manipulation of the audio signal (in EQ and maybe use of delay) may have a place in practical situations. Audyssey seems to "work" for me at making the best of a bad job!

None of these devices can work because of the way you listen.

You make critical judgement of what you hear by listening to the first arrival directly from the source. This is despite the fact that it may be less loud than early reflections and reverberant energy.

You only thing you can alter is the direct sound and if that's wrong, you notice.

However, if you're not a critical listener or just want background music, it may help, but I wouldn't waste the money. The technology has been developed for public address where sound men can have big problems.

I've been fascinated with all this since I had a wind up gramophone in the fifties and in my experience rooms vary, but not by enough to prevent you quickly adjusting and not noticing what it's doing to your hi fi.

The only time it is an issue is when you visit a friends hous'e and his system doesn't sound as good as yours. It may not be the system, but the room and after a period of acclimatisation, you'll know better.