Are separates on borrowed time?

[lindsayt]

In my system when I actively bi-amped it I had:

Source connected to Ashly xr1001 active crossover to SET valve amp for the midrange and treble and solid state amp connected directly to the bass units.

OOI on what basis do you choose the cross over frequencies, and is there any inherent difficult with using such different amplification for the different drivers?

(As an aside, this sort of active setup is the very antithesis of the thread title! )

Crossover frequencies and slopes were chosen on the basis of replicating the passive crossover frequencies and slopes. The Ashly active crossover allowed better adjustment of the crossover frequency but only allowed 24 db slopes. The Pioneer had a series of fixed crossover frequencies - so I used the nearest one which is 100hz too high, but the Pioneer allows 6, 12 or 18 db slopes, allowing me to use the 6db slopes. The speaker manufacturer also made an active crossover for these speakers, but these are rather rare and get snapped up very quickly when they do come up for sale. The midrange and bass drivers of these speakers have a lot of overlap. When I experimented with different crossover frequencies from 200hz up to 800hz I got some subltle differences in the sound, but I couldn't decide on any overall personal preference on the test tracks that I used, making me think that crossover frequency is not particularly critical on these speakers.

My solid state amps have more gain than my valve ones. This means that you need a volume control after the active crossover and before the power amp that has most gain. Both of my active crossovers have this built-in. I set the volume for the higher frequencies at max and the volume for lower frequencies at about one quarter. Sometimes I give this a little nudge in response to the tonal balance of particular recordings. Instinctively one might think that using a mixture of valve and solid state amplification would result in the bass sounding divorced or of different character to the midrange and treble. In practise they work cohesively together.

Yes this aproach is the antithesis to the thread title. If you're buying new, the price for such a stack of boxes does come into it. When buying 2nd hand you can buy loads of boxes cheaply. The Ashly cost me £130, the Pioneer £170. My valve amp was pretty pricey at £1650, plus £300 in new valves every 5 years. On a budget I wouldn't sacrifice a huge amount of sound quality by swapping it for a much cheaper solid state amp. Although I do have a definite preference for valves for the midrange. For the bass I use a solid state amp which cost me £650. I've recently bought two solid state amps for £150 which sound at least as good but are a PITA domestically. The speakers cost me £500.

My feelings are that as long as there is a plentiful supply of good quality inexpensive (mostly 2nd hand) seperates, hobbyists like myself will continue to use them. I also think that turnkey solutions such as the AVI's will continue to be popular.

 

[lindsayt]

In my system when I actively bi-amped it I had:

Source connected to Ashly xr1001 active crossover to SET valve amp for the midrange and treble and solid state amp connected directly to the bass units. When the Ashly started getting a bit hummy I replaced it with an LDR volume control feeding a Pioneer SF-700 active crossover. So yes the audio signal was split first before hitting the power amps.

Thanks for the clarification lindsayt.

Could I also ask. Were the amps connected directly to the drivers or was there still a passive crossover in between the amps and the driver (even though the signal had already been split by the active crossover earlier in the chain)?

Good question. The bass units in my actively bi-amped system are connected directly to the amps with no passive crossover between them. The lower passive crossover unit to the midrange unit was modified to change it to a capacitor that would cross-over at a lower frequency than the standard one. This is to provide protection to the midrange drive units in case of an amplifier fault. The passive crossover between midrange unit and tweeters remains unchanged and in the signal path. I took this approach on the advice of the Yahoo users group for my speakers where I bowed to the general consensus of advice that actively bi-amping them was the way to go with them. Advice with which I fully agree now that I've tried it.

 

[lindsayt]

What about distortions introduced by the active crossover? That electronic box of tricks that sits between the pre-amp / volume control and power amps? Is anyone seriously claiming that active crossovers introduce no distortions?

Apparently an active crossover only produces about 0.001% distortion. But a passive crossover produces about 1% distortion.

0.001% distortion in an active crossover? What type of distortion is that, or is it a total of all distortions? In which case what weighting do you give to the different types of distortion? Also which particular active crossover are we talking about and which passive crossover? What about all the other active and passive crossovers? Have they been measured?

My definition of distortion in this case is anything that changes the input signal - apart from separating it into different frequencies and making it larger or smaller (equally across the whole frequency range) as some active crossovers provide some amplification gain or attenuation.

What frequencies are we talking about for these distortion measurements? What signal size and type?

Are you aware that THD+N distortion as a percentage in solid state amps increases as the output power decreases? I would expect a similar characteristic in solid state based active crossovers. In active crossovers we can have mind-boggling small output power levels when we're talking about low level musical details. Microwatts!

THD+N is only one type of distortion measurement. There are other types of distortion.

I would like to see a comprehensive set of distortion measurements for all types of distortion at all frequencies and all power levels and all input signal types found in a hi-fi system in actual usage.

In the absence of that I will continue to use my ears to tell me which sounds less distorted.

 

[Anonymous]

More distortion means less accuracy, and vice versa, i'm sure we all agree on that? And accuracy is the goal of *most speaker designers, like that nice chap who founded PMC, the guys at AVI, ATC and many others, and all pro audio speaker designers/manufacturers, whether using active or passive speakers.

Now total accuracy is obviously not possible, but when getting as close to it as possible is the primary goal, why do those manufacturers seeking to do so use active speakers? It's because they're more accurate, because they distort less (all other things being equal).

*obviously there's a multitude of manufacturers that make passive hifi speakers, that cater for the very lucrative home audio market, and who's primary goal isn't accuracy, if it was they'd only make active speakers.

 

[John Duncan]

This is such a lot of shite...

 

[Dave_]

*obviously there's a multitude of manufacturers that make passive hifi speakers, that cater for the very lucrative home audio market, and who's primary goal isn't accuracy, if it was they'd only make active speakers.

Yes, yes, we know.

Most manufacturers of passive monitors are out to rip off deluded audiophiles, whilst those who manufacturer actives are all ultruists.

:roll: :wall:

What about those that do both, suppose they're funding their ultruism by ripping off deluded audiophiles?

 

[the record spot]

This is such a lot of shite...

What hea said. Several times over.

My take: unless you've got the academic and / or engineering background to comment on this, then it's secondhand news (ta Fleetwoods) off somebody else's website. No offence meant, but this car stopped running on exhaust fumes so long ago there isn't even a car left.

 

[Anonymous]

This is such a lot of shite...

What part, JD? Why do the likes of Barefoot Sound, Adam, and Dynaudio make active pro monitors then? There's simply no getting away from the fact that they use actives because they suffer less from distortion, that's all i'm saying. I'm happy to stand corrected if i'm wrong, but i don't think i am.

 

[Anonymous]

This is such a lot of shite...

What hea said. Several times over.

My take: unless you've got the academic and / or engineering background to comment on this, then it's secondhand news (ta Fleetwoods) off somebody else's website. No offence meant, but this car stopped running on exhaust fumes so long ago there isn't even a car left.

So, RS, most pro monitors are active because their designers have been hanging around HDD Audio for too long and are thus brainwashed? They should have used passives because they distort less? Is this what you're saying?

 

[Anonymous]

*obviously there's a multitude of manufacturers that make passive hifi speakers, that cater for the very lucrative home audio market, and who's primary goal isn't accuracy, if it was they'd only make active speakers.

Yes, yes, we know.

Most manufacturers of passive monitors are out to rip off deluded audiophiles, whilst those who manufacturer actives are all ultruists.

:roll: :wall:

What about those that do both, suppose they're funding their ultruism by ripping off deluded audiophiles?

So passives distort less? That's why when you bought your active Dyns you told me it was the best thing you ever did? Because you wanted distortion?

 

[shooter]

This is such a lot of shite...

What part, JD? Why do the likes of Barefoot Sound, Adam, and Dynaudio make active pro monitors then? There's simply no getting away from the fact that they use actives because they suffer less from distortion, that's all i'm saying. I'm happy to stand corrected if i'm wrong, but i don't think i am.

Probably for convenience.

Studio's around the world use both passive and active set ups, it's got nout to do with distortion as every ear is different, and each ear prefers one sound over another. Some ears like PMC, some like Adam and so on, your really grasping at everything should sound the same, why?

 

[the record spot]

This is such a lot of shite...

What hea said. Several times over.

My take: unless you've got the academic and / or engineering background to comment on this, then it's secondhand news (ta Fleetwoods) off somebody else's website. No offence meant, but this car stopped running on exhaust fumes so long ago there isn't even a car left.

So, RS, most pro monitors are active because their designers have been hanging around HDD Audio for too long and are thus brainwashed? They should have used passives because they distort less? Is this what you're saying?

Sorry Max, not biting. Your words, your interpretation, not mine. FWIW - you're miles off.

 

[steve_1979]

Good question. The bass units in my actively bi-amped system are connected directly to the amps with no passive crossover between them. The lower passive crossover unit to the midrange unit was modified to change it to a capacitor that would cross-over at a lower frequency than the standard one. This is to provide protection to the midrange drive units in case of an amplifier fault. The passive crossover between midrange unit and tweeters remains unchanged and in the signal path. I took this approach on the advice of the Yahoo users group for my speakers where I bowed to the general consensus of advice that actively bi-amping them was the way to go with them. Advice with which I fully agree now that I've tried it.

By my (admittedly rather limited) understanding, if you keep the passive crossover in between the amp and the driver it'll still cause distortion and effect the way in which the amplifier controls the movement of the driver (even though you not actually using it as a crossover).

I suspect that this is one of the reasons why you didn't hear much of an improvement over the passive version of the same speaker.

Source connected to Ashly xr1001 active crossover to SET valve amp for the midrange and treble and solid state amp connected directly to the bass units. When the Ashly started getting a bit hummy I replaced it with an LDR volume control feeding a Pioneer SF-700 active crossover.

Due to this setup being a DIY active speaker it would've been quite a compromised design.* With a properly designed active speaker the amplifiers and crossovers are designed and made from scratch to best suit the speakers that they're going to be driving. With the active speaker setup that you made you just used whatever amplifiers and crossovers that were available to you at the time and these wouldn't be an optimally match for the speakers that you were using.

I suspect that this is the another reason why you didn't hear much improvement over the passive version of the same speaker and it wasn't really a fair test of actives vs passives.

* This isn't intended as a dig at you personally. It's obvious that you have quite a bit of knowledge about speakers.

 

[steve_1979]

Damn! I clicked the reply button instead of the edit button. :wall:

I should have used the word 'optimal' not 'optimally' in that last post.

 

[John Duncan]

This is such a lot of shite...

What part, JD?

Practically every word.

 

[eagle123]

You can upgrade separates but not the amplifier in the active speakers, you have a choice of tailoring the sound you require different amps, sources speakers and cables you limited to what you can do with a active speaker

 

[Phileas]

... tailoring the sound... you limited to what you can do with a active speaker

You can use EQ - should be easier than mucking about with different amps, cables(!?!) etc..

 

[relocated]

Is this something we can agree and move on from?

ray:

I shouldn't think so for a nanosecond, but some man love before we get back to disagreeing might make for an interesting diversion.

:rofl: :rofl:

 

[oldric_naubhoff]

Why do the likes of Barefoot Sound, Adam, and Dynaudio make active pro monitors then?

have you considered that maybe market demand has something to say here? if you ran a recording studio would you rather have a set of passive speakers and a large amp or just active speakers that are just as good passive set up but cost more or less as much as passive speakers alone. well, if it was my money on the table I'd definitely go for more cost effective solution. especially since there's a lot more to equipping a recording studio then just buying a set of speakers. and I think most studio engineers think along those lines. actives are cheaper, therefore so successful in pro audio world.

There's simply no getting away from the fact that they use actives because they suffer less from distortion, that's all i'm saying. I'm happy to stand corrected if i'm wrong, but i don't think i am.

well then, how would you explain the fact that for instance Dynaudio Air 20 pro monitors are hybrid designs; incorporating active and passive design? woofer is active but mid/ tweeter section is passive (powered with common amp). are Dynaudio crazy if they committed such blasphemy?

speaking of Dynaudio. do you think that when they released Evidence or Confidence line of their passive speakers they didn't know what they were doing?

 

[Alec]

Is this something we can agree and move on from?

ray:

I shouldn't think so for a nanosecond, but some man love before we get back to disagreeing might make for an interesting diversion.

:rofl: :rofl:

Alas, deaf ears and all that.

Thank God for my total lack of technical know-how.

 

[bigblue235]

Ooh, no offense, but it's as if you're just regurgitating stuff you've been told rather than having as much of a genuine understanding of what you're talking about as some of the people who are disagreeing with you. I have next to no understanding either, but I don't try to hide that fact. But I am sure there's a lot more to it than just repeating "An active crossover is more accurate".

Not all Passives are of similar quality, so why should being Active be used as a benchmark? Don't Abbey Road have a pile of Classe and B&W?

 

[chebby]

Not all Passives are of similar quality, so why should being Active be used as a benchmark? Don't Abbey Road have a pile of Classe and B&W?

Yeah, but what do they know?

They could have saved a packet with an Apple TV and GarageBand.

 

[bigblue235]

They could have saved a packet with an Apple TV and GarageBand.

... into ADM 9Ts?

 

[John Duncan]

Not all Passives are of similar quality, so why should being Active be used as a benchmark? Don't Abbey Road have a pile of Classe and B&W?

Yeah, but what do they know?

They could have saved a packet with an Apple TV and GarageBand.

Or a $300 Sony AV receiver.

Although I doubt they'd do it on money-saving grounds, since I doubt that Abbey Road has to pay for anything; I suspect that any manufacturer (of active or passive equipment) would give it away for free just to have it in there.

So they just choose the stuff that sounds best...

 

[Anonymous]

Ooh, no offense, but it's as if you're just regurgitating stuff you've been told rather than having as much of a genuine understanding of what you're talking about as some of the people who are disagreeing with you. I have next to no understanding either, but I don't try to hide that fact. But I am sure there's a lot more to it than just repeating "An active crossover is more accurate".

Not all Passives are of similar quality, so why should being Active be used as a benchmark? Don't Abbey Road have a pile of Classe and B&W?

Of course i'm regurgitating stuff, who hasn't in this thread? stuff that i've read about active speakers, that you too can read if you want, though you mightn't believe it, or want to believe it, that'd be up to you.

I do believe it, having owned and heard several active speakers, i noticed the clarity of the sound from them, and i put that down to them being active, logically, as it tallies with the stuff i've read about actives.

Not everyone wants accuracy, but if you do, IMO and based on my understanding of what i've read and my experience, active speakers are the way to go, this is backed up by the fact that they're mainly used in recording studios where accuracy is the primary concern.

So, as i said before. An active version of the same passive speaker will IMO and given my understanding of the stuff i've read, distort less, assuming both speakers have sufficient amplification and are competently designed (like the ATCs), and less distortion means greater accuracy.