Active Cum Passive Loudspeaker Is It Possible ?

[jsa_ind]

Hi All !

Can someone please advice ?

I wish to build an Active Cum Passive Loudspeaker...a two way system

For the lows I wish to use a push pull arrangement of loudspeakers with an active amp based on Tripath TK2350. I also wish to use a "deqx" crossover module. For the highs I wish to use a normal amplifier (integrated or separate)

Is there a circuit, by which I can take the outputs of a speaker terminal and plug it to this loudspeaker & have a frequency division of the low & highs ? Yes there is a preout option from the preamplifier. But I was wondering if this could be achieved using conventional loudspeaker cables.

Here is the prefect scenario.....Amp connected to loudspeaker via loudspeaker cables....frequency division takes place....the lows get routed to the active bass section through "deqx" the remaining signal is amplified and passed on to the tweeter. The output levels of the tweeter are so compensated so that it is always reproducing the same dB as te woofer (can deqx do it ?) As the volume increase or decreases the output level of both the tweeter & woofer decrease so as to maintain the same relative dB level.

Can this be achieved, with sonic degradation & excessive power loss ?

If so please help me with a circuit or advice !!

If not, please tell me so and if possible suggest an alternative, where by one does not have to connect a separate signal cable & a loudspeaker cable to the loudspeaker.

Thank you !

Regards,

Junia

[Stocker]

Are you unaware of the concept of a "crossover" or do you want something new and different?

[ShinOBIWAN]

What are you on about?

It seems like your trying to make things intentionally complex when the situation can be remedied with a much simpler solution.

Also your willing to pay $3000 for a DEQX and not use it to its full potential? It alone could do all your asking without trying to speaker level signals into line level active electronics.

I really hope I'm missing some detail here that makes the solution your looking at 'beneficial'.

[jsa_ind]

Hi All,

Let me clarify.

I wish to experiment using a DEQX OEM module not the regular $ 3000 version, design a loudspeaker with an active bass section, but with a tweeter which can be driven with just about any amp.

Is this possible ?

If so I think there could be a potential. Because with the active amp & DEQX crossover module you could take care of all the intricacies that goes into speaker design with regards to the bottom end. Yet have anyone use their regular amps to drive the top end, using regular loudspeaker cables. What little I know it does not seem possible.....but I thought someone might have a solution I don't know about.

Actually Dynaudio were suggesting something similar in their C5's, which never came into existence. So I do believe it is possible, but don't know how that can be achieved without a preout and two separate in built amplifiers with an active crossover like DEQX

If this idea is wacky...I apologize I just wanted to ask you folks for advice.

Thanks a million !

Regards,

Junia.

[wintermute]

well it sounds like you are thinking of using two amps, if this is the case then all you need is an active crossover before the two amps which splits the line level signal into low and high components, which are fed separately to the two amps...

Now from your first post it sounds like you only want one wire going to the speakers??? if so then you could put the active xover and amps in the speakers and just run the line level (if the distance isn't to great) to the speaker.... however my personal preference would be to live with two speaker cables.

I'm not familiar with the DEQX but I'm assuming it is some sort of multi-channel digital crossover which I'm sure you could just take your two outputs off and feed to two separate amps, and once again have one drive the woofer and one drive the tweeter.. simple really.

You might want to read this article ---> http://sound.westhost.com/bi-amp.htm

Tony.

[sreten]

Originally posted by jsa_ind
Hi All !
Can someone please advice ?
I wish to build an Active Cum Passive Loudspeaker...a two way system ........
Junia

Hi J,

basically your scheme although perfectly feasible and relatively
simple to implement is not a good idea due to one fatal flaw.

The flaw is that the dynamic range of the amplifier driving the
treble is severely compromised by also having to swing normal
bass voltages (but not deliver the current) effectively limiting
output levels to be similar to using the amplifier full range.

/Sreten.

[Sjef]

The whole idea won't work with the DEQX simply because the DEQX is a FIR digital crossover with a pretty long latency between it's in and outputs. This latency depends on crossover configuration and amount of correction you want to use but can go up to 33 mS, that's like placing your woofers 10 meters behind the mids/highs in your listening room. While set to either Butterworth or Linkwitz filtering instead of FIR the latency will be reduced a lot but wil still be in the order of some miliseconds, and ask yourself what's the use of implementing a DEQX DSP crossover when you cannot use what it was designed for anyway. It's real power lies in the crossover between mids and highs without any fase shifts / group delay.