TAD Compression Drivers - Opinions on TD-4001 vs. 4003?

[Ian Mackenzie]

Simon,

Thanks for those nice pics.

My suggestion before looking at another crossover system would be to borrow a top flight high current amp of at least 200 watts a side and see how it does.

Something like an ME or a butch Musical Fidelity.

The Tad twin system is a notoriously a difficult load to drive.

You might be surprised just how good they sound.

The next step would be to look at a proper MTM crossover network as there could be a degree of vertical polar lobing with those crossovers that are designed for both woofers together under the horn.

I have had discussions with other Tad horn users and the notch filtering is not that difficult to arrange if you have suitable test equipment. But it is very system dependant with location of the horn and other components on the baffle.

If I were you I would contact Krix or VAF Research in SA and see of you can come to some arrangement as it really needs to be done on site to make a proper job of it. (Or you could deliver a cabinet to their facility). Its not worth screwing around with frankly.

Once you have the proper data someone like Greg Ball on the east coast(ex Mark Levinson) can look at the suitable active crossover.

[pos]

These horns are really nice looking!

So are you going to integrate the 703 ?

[Mr. Widget]

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Do you have a contact adress of this company?

I assume you mean the maker of the TAD TH-4001 clones?

http://www.classicaudiorepro.com/page8.html


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[richluvsound]

Guy's , does anyone have the drawings for a 4001 horn ? Please PM me .

Rich

[Charles0322]

Great pics, great thread and definitely great sounding

Congrats on this worthy pro system

[Mondie]

Thanks for all the kind words, it has been a very worthwhile project. l must admit at times l was a bit nervous but alas the end result is sensational My timing was very fortunate too, with the rapid decline of the A$ l could not justify the cost of doing this project today, the Australian currency has devalued 55% since l started this thread not so long ago

Ask a local person skilled in crossover design to inspect your crossovers. It seems that all components are wired to the outside of the epoxy so they are measurable with a LCR Meter.

You just may be onto something there, a lot of wires run from out of the black boxes. l guess this would only fall down if multiple components were connected but even then, that will only be a drama if there is a mix including inductors, which l suspect is unlikley. Now l just need to find someone to do the measuring, l will look into this in the next few months.

Simon,

Thanks for those nice pics.

My suggestion before looking at another crossover system would be to borrow a top flight high current amp of at least 200 watts a side and see how it does.

Something like an ME or a butch Musical Fidelity.

The Tad twin system is a notoriously a difficult load to drive.

You might be surprised just how good they sound.

The next step would be to look at a proper MTM crossover network as there could be a degree of vertical polar lobing with those crossovers that are designed for both woofers together under the horn.

I have had discussions with other Tad horn users and the notch filtering is not that difficult to arrange if you have suitable test equipment. But it is very system dependant with location of the horn and other components on the baffle.

If I were you I would contact Krix or VAF Research in SA and see of you can come to some arrangement as it really needs to be done on site to make a proper job of it. (Or you could deliver a cabinet to their facility). Its not worth screwing around with frankly.

Once you have the proper data someone like Greg Ball on the east coast(ex Mark Levinson) can look at the suitable active crossover.

Hi Ian,

Thanks for your ideas, l have been thinking about contacting Greg about his active crossovers as a way of getting into active. l understand he is using Mosfets not OpAmps which l like.

The melody Valve amps shown in some of the pics certainly struggled to control the woofers, the sound was pretty disjointed and the bass uncontrolled. l am now using a pair of Xindak 200wpc Class A Monoblocks, absolutely wonderful amplifiers. l cannot recommend them highly enough, they transformed the TAD's sound completely.

These horns are really nice looking!

So are you going to integrate the 703 ?

Maybe in the future, l have found so far that l do not feel like l am missing out in the top end, but maybe ignorance is bliss

Cheers,
Mondie

[Mondie]

Time for an update



l just picked up an Ashley XR2001 from eBay at a good price so a move to active is on the cards for 2009. At this stage l dont have the additional amplifiers but will keep an eye out for something suitable. Initially l will try 2 way and see what improvements l pick up and the in the future, add a pair of ET703's.

l have one question on driver protection. For those who run the 4001 in an active configuration how do you protect it from blowing? l have been told a fuse by one user and a capacitor by another, which seems like a bad idea to me. A fuse seems like the best protection but what value?

All the best for 2009.
mondie

[Robh3606]

Hello mondie

Normally you use a Capacitor. Fuses blow but can and will pass DC before they do. A cap is a much safer option to keep DC out of the driver and what is traditionally used. That said a fuse would be better protection for feedback as a cap will not protect against a high power in band spike which potentially is just as dangerous.

As long as you don't go messing around with cables and unplugging things with the power on I doubt your going to have a feedback like issue at home. I have been running mine for years and never had any kind of high frequency oscillation or spike.

I don't use Tads but a compression driver is a compression driver

Rob

[Mondie]

Hi Rob,

Thanks for the pointers. What value cap is used to provide sufficient protection without causing phase issues?

Cheers,
mondie

[pos]

The rule of thumb is to choose a cap value so that the corner frequency is half (or even less) the frequency of your active crossover. You have to check the impedance of your driver and horn combo to calculate this value.

[Mr. Widget]

On my nominally 16 ohm TAD TD-4003 drivers I use an inexpensive Bennic 47uF polypropylene cap. That works out to ~200Hz and my actual crossover is fourth order at 800Hz. When I remove the cap or place it in the circuit I can hear no change.


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[Ian Mackenzie]

Have you tried CCing the protection caps?

[Mr. Widget]

Have you tried CCing the protection caps?

You know, that was suggested, but I have literally shorted them out on the fly and heard no change and listened to them both in and out of the circuit. They don't seem to affect the sound at all. If they did I sure as hell would give it a try.


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[Ian Mackenzie]

I would definately keep the capacitor in there for anyone looking over their shoulder at this thread. It only takes another family member to turn the wrong thing off first when your not around and ooch!! Its bad enough watching your woofers come out to meet you.

[louped garouv]

I use an inexpensive Bennic 47uF polypropylene cap.

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does the use of these protection caps affect phase considerations?