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Project 4000 Speaker Renovation


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JA,

I think we must have found the same article on the driver. My specs are the same, though the print was a bit fuzzy and couldn't work out if Pe was 100 or 180. Not sure if that makes a difference or not. The specs I used are shown in the screen shots on page the attached file. The software I used fills in the missing spec's based on what is known. I see what you mean about the LF trade-offs - playing with the tuned frequency subtlely changes the shape of the curve.

Regards [/b]

the middle graph has a different volume measurement to the other two which has 80L. I'm assuming that was a bit of an opsy??

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the middle graph has a different volume measurement to the other two which has 80L. I'm assuming that was a bit of an opsy??

[/b]

It is different but not a mistake. The middle graph depicts what the software calculates as the optimum volume for this driver (112 litres or so) whereas the other two graphs were constrained by the actual size of the existing boxes (80 lites). So, most of the difference in perfomance between the three graphs is caused by using less than ideal box volume. However, adding a port (middle line in the SPL graph) certainly helps bring the result a lot closer to the optimum. Think next weekend will be spent working out safest way to cut the holes. Seems to be three choices:

Bush carpenter - pilot hole, jig saw and bog in the port tube - don't think so!

Hole saw - only if lucky to find one the right dimension

Router - most likely - just got to practice with making up the right sized template

FUN!

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  • 9 months later...

Although now an old post, I also have these speakers and am looking to port the enclosures. I would prefer to be able to place the port on the front, but will most likely have to settle with placing it on the back due to lack of space on the front baffle. I am looking at tuning the enclosure to 40Hz with 2 x 66mm or 1 x 90mm port.

I believe the crossover is too complex in its present form and the speakers would probably sound superior with a simplified and redesigned crossover. I don’t like the wire, inductors, resistors or capacitors that were originally used. Unfortunately finding Philips driver specs is incredibly difficult.

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  • 1 month later...

Have read this post (though old) with great interest. When ETI and David Tillbrook published this design I too embarked with it. A friend got me to help with the build for himself and while he was happy with outcome, I was never happy with the low frequency performance from such a large enclosure. I think it was a short time later that Electronics Australia (Aug '82) published a Jaycar 10" Etone subwoofer design that had smaller enclosure dimensions than that of the Philips 12" woofer. So I decided to make a system based on the ETI4000 xover and with this subwoofer driver. But I left my run too late and the Philips 7" woofer was no longer available. I had to use a Vifa 6.5" C17 WG-29. The midrange and tweeter were as specified. I love the Philips midrange but not the tweeter. I have since decided to swap the tweeters for Vifa D25AG which are 6 ohms. I don't think the woofer combination is at its best and I don't want to lose the drivers particularly the Etone subwoofer (one for each side, one is the original American corrugated edged cone, the other the foam edged local cone) as it has a very good response flat to 400Hz.

It is all a bit of a mess now and after reading some articles about xovers, I now know that major alterations are required. I need a little more upper bass output (I'd say the range between 150 and 400) and a good deal less tweeter output (6 ohms likely the problem here as it's SP is 89dB 1w1m).

Any help would be welcomed. I would also be interested in what eventuated with how far Speedorhaste has got!

cheers

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Just found some info on the Philips Dome MR and tweeter. My midrange is the AD02160 which has the prodruding dome.

The ETI 4000 was also sold with a recessed dome midrange AD02110 by Jaycar in their '95 catalogue. It's specs are 550-5kHz Res Freq 360Hz Flux Density 0.9T and 100W system power (no sensitivity spec available here).

The Philips tweeter AD11610/T8 is 1-22Khz, resonance 1250Hz, Sensitivity 95dB 1w/1m 8ohms. (I'm sure this is the same as the AD01610).

My Vifa D25AG tweeter is 6 ohms 1.5-35kHz resonance 850Hz sensitivity 89dB 1w/1m.

No specs for my 6.5" Vifa C17 WG. But the C17 WH version has a larger magnet and sensitivity around 90-91 dB/2.8 volts whatever that may mean!

I may have to dig through some attic back issues for more info.

:blush:

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  • 1 month later...

Seems to be no further interest out there but just in case: I noticed that there may be a design/publication error for the 4000/1 crossover that was corrected for the later 4000/2. It seems to me the 4000/1 0.8mH inductors should have been 0.5mH. The 3.3 cap/0.8 ind combination makes little sense!

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Just a thought: you may be able to find a second hand active crossover.

It may be cheaper than buying expensive high grade discrete components. That will also offer you the chance to play with xo frequencies until you find the optimum. At that point you may wish to seel your active xo and buy the appropriate values of discrete components.

cheers

Doug

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Just a thought: you may be able to find a second hand active crossover.

It may be cheaper than buying expensive high grade discrete components. That will also offer you the chance to play with xo frequencies until you find the optimum. At that point you may wish to seel your active xo and buy the appropriate values of discrete components.

cheers

Doug

yes, a good idea. I think I remember Kenwood introducing active crossovers sometime in the '70's. A friend had one. All those wires and amps was a bit of a hassle...but an absolute way of combining drivers. Just need the pink noise generator and something that tells me how to adjust it all, and then a whole new listening room to get it right....

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  • 7 months later...

Hi All,

I am looking for help.

I have a complete set of ETI 4000 4 way speaker system as well as the 4001/1 three way system as well. I have all the Phillips drivers and the Tilbrook designied Cross over.

Due to a water problem I need to replace the enclosures.

Does anyone know where I could get these boxes, or some place that may build them??

If any can help it would much greatly appreciated.

Pablo

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  • 2 weeks later...

I haven’t finished my rebuild of my 4000’s, but I did put a fair bit of work into redeveloping the crossover with some pro assistance, but wasn’t happy with any of the changes. The original crossover is too complex, but isn’t worth a total redesign. The original wire they specified in the article was a joke. The Philips tweeter in the design was a very nice tweeter, probably the best of all the drivers in the 4000. My 4000 is in storage until I can be bothered having another go at it. My ~40l Vifa design using a D25AG tweeter and dual P17WJ woofers effortlessly trounces the 4000’s. At one stage I was in email contact with “Speedorhasteâ€.

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Thought I would post this as a way to inspire people who own the 4000’s

Consider the following…

Leave the big inductors, they are iron core but are good quality, not worth replacing with air core

Replace cheaper wire wound resistors with at least the ww vitreous enamel type or MOX type if you want too.

Replace the components that are in series with the tweeter and midrange drivers. (as these have the most effect on sound quality)

Upgrade wiring, the original wire is substandard.

Port the speaker, the woofer is actually designed for a ported enclosure (use at least 90mm diameter pipe). You will have determine length through trial and error.

Don’t dope the woofer; if you do you will need to redesign the woofer section of the crossover.

Separate the woofer section from the rest of the xo, so you can bi wire. (not difficult to do).

Only do these mods if your drivers are working fine.

Edited by linnit
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Hi Linnit,

Sounds good I always thought about separating the x-over bits and placing them adjacent to each driver and hook it all up with descent speaker cable.

I am already onto replacing the inferior resistors and capacitors.

At the moment I need to have 2 x new boxes made, as both my 4 way and 3 way boxes have been damaged with water whilst in storage, and I have had 2 of my woofers damaged by pesky mice.

I thought to have at least the 4 way set of boxes made as per the originals, that why I was trying to get feedback from “speedorhaste” to see he/she got on.

I would also love to get my hands on 2 x of the original woofers if anyone has a pair that they no longer want and are willing to let go, id be prepared to take them for the right price.

As I mentioned before I had the ETI 4000/1 3 way system in a 100L vented box and the woofers sounded much better than the 4000 4 way system in the 80L sealed box.

Any way given that I am going to have to get 2 new boxes built please let me know if any one has any suggestion about new size for 4 way boxes.

And please if anyone has a pair of the original woofers I would rely like to get them, (almost kill for them) NO just kidding, or the woofer specs so I can attempt repair job with a local repairer.

Cheers Pablomez

Edited by Pablomez
spelling
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Philips AD12250/W8 woofer specs

Fs (Hz) 25

Pe (W) 100

Qts .34

Re (Ohms) 7

Vas (l) 250

Qes .43

Sd (cm2) 530

Rg (Ohms) .5

Qms 1.6

Vd (cm3) 850

It would probably be debatable to go to the trouble of having the boxes rebuilt as well as 2 woofers repaired. Unfortunately I can’t see you obtaining a pair of the Philips woofers. I think you would find that a lot of other woofers would surpass it. Like I said the best driver in the 4000 was the tweeter. The crossover is not really designed correctly, trying to get a 4-way sounding good isn’t easy and Tilbrook only used textbook crossover design. I would start saving for a better pair of speakers. With the mods I mentioned it should cost no more than $100, but that was only if everything was working fine to begin with.

Sounds good I always thought about separating the x-over bits and placing them adjacent to each driver and hook it all up with descent speaker cable.

I am already onto replacing the inferior resistors and capacitors.

No need to scrap the XO circuit board, it is fine for these speakers. I only suggest separating the woofer for bi-wiring, look at the board it is easy to do. Don’t worry about replacing the 47uf BP caps with Polypropylene as they wouldn’t be worth the cost to do so.

Edited by linnit
added extra info
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  • 11 years later...

I know it's a good 12 years since this thread has been replied to, however I am hoping to revive it as the new owner of these speakers. They have been ported to correct specifications and I'm very happy with them but I find the top end to be extremely lacking. They are certainly not forward or fatiguing, they are the total opposite, and I find myself needing to up the treble on the preamp to the 2'oclock position, something I've never needed to do on many sets of speakers. The speakers also have upgraded jantzen caps at decent expense. If anyone can please help me I'd be very appreciative. 

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Listen to the hf drivers up close, are they both working?

Check the crossover components the feed the hf drivers, are they of the correct value?

Are the components within spec?

Are the components installed with the correct orientation and properly soldered?

Are the hf drivers connected with the correct phase?

 

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On 25/03/2007 at 11:08 AM, Speedorhaste said:

 

Project 4000

For ease of reference, I'll refer to the speakers as "The 4000".  That was their project name at inception as explained later.

 

 

I'm pretty sure I built those, in the mid 80s.  :)  And I enjoyed listening to them

 

I changed the physical design by

  • making them out of 30mm mdf, and
  • giving them a triangular shape so the width of the cabinet at the tweeters was much less than the width at the woofers.

They may still be out there - I sold them when I moved house in 1989.

 

Andy

 

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1 minute ago, andyr said:

 

I'm pretty sure I built that kit, in the mid 80s.  :)  And I enjoyed listening to them.

 

I changed the physical design by

  • making them out of 30mm mdf, and
  • giving them a triangular shape so the width of the cabinet at the tweeters was much less than the width at the woofers.

They may still be out there - I sold them when I moved house in 1989.

 

Andy

 

 

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On 22/10/2020 at 5:31 AM, pwstereo said:

Listen to the hf drivers up close, are they both working?

Check the crossover components the feed the hf drivers, are they of the correct value?

Are the components within spec?

Are the components installed with the correct orientation and properly soldered?

Are the hf drivers connected with the correct phase?

 

I have certainly listened to the tweeters up close and they're working fine. I'll check all the other possibilities you mentioned. They sound beautiful but need some power for the soundstage to jump out of the speakers. Once I hit that sweet spot, I can close my eyes and point out where the band is. Pretty impressive considering theyre huge 4 ways. They've been ported correctly and go down to 26hz pretty well with a steep drop in db below that. Bass that can certainly be felt in the chest. I just find it strange that I'm increasing the treble on my preamp. Only from midday to 2 o'clock. Maybe I'm being picky. They certainly don't sound muddy, just need a slight nudge in the top end, almost as if the tweeters aren't sensitive enough. Maybe it's just the design, and I'm being a sook for having to adjust the treble on preamp.  Either way, thanks for the suggestions. I'll go through the list. 

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