What?
Oh no..
If I'm "lucky" I will relocate to premises with less space before that project enters the POC state...
The stacking originally was to gain some more level in the low end, last not least to get a larger vertical listening window.
What cannot be seen on the picture is that the baffles are to be center hinged for experimenting "x-baffle?", and the AMT's mounted on their own piedestall, still full dipole.
I would think so too! The ATC is a beast... especially the S version
ESS single or dual?
Pharos: Yes, 2cf means 2 cubic feet. The TAD driver I'm referencing works very well sealed between 1-2 cf. Years ago I built a 1.5" thick laminated cabinet for a pair, with inner panels that were angled for non-parallel walls. If I recall, it was 1.6-1.8 cubic feet inner dimension, but net a bit less than that. The driver is 100db with 1 watt. They are fabulous sounding, if you don't try to cross them too low. 200 is the recommended number, I've done 160 with some success. I have a stack of them, so am determined to complete a speaker based around that critical frequency range. Especially since I have several TAD subs sitting around that COULD be used.
Pharos: size of room...my AV room/work area is 21.5' x 22.75" x 9'. So nice size. The other room I might take them to if they turn out to be a great success is 23'x35' with a sloping ceiling from 8' up to 12' or so.
The ESS is typically around 100db or slightly higher efficiency too, as you know. The Klipsch people like to double them up so they can cross at 600hz or even lower. No way am I going to do that. Right now I'm crossing at 800, and they play very loud, and sound great.
Fedde: Thanks for the comment on that 6". I rather like the idea of trying something in that range. A friend suggested the older Audax PR17MO,which is a well behaved driver, and whose efficiency matches up really well. Lots of good choices there. I might be tempted to try something, because they could always be used on another project if the decision was made to go straight from the TAD to the ESS. By the way, I've been to Eindhoven on business.
The weak link for my project is likely trying to get these drivers to play nice with the new (on my shelf) 92db/watt 15" woofers. The frequency range is fine, but it would lag a lot in efficiency. This is all active though.
My cabinet maker is finishing up my latest housing project this coming week, so I'm hot to make a decision while he is available.
Pharos: Yes, 2cf means 2 cubic feet. The TAD driver I'm referencing works very well sealed between 1-2 cf. Years ago I built a 1.5" thick laminated cabinet for a pair, with inner panels that were angled for non-parallel walls. If I recall, it was 1.6-1.8 cubic feet inner dimension, but net a bit less than that. The driver is 100db with 1 watt. They are fabulous sounding, if you don't try to cross them too low. 200 is the recommended number, I've done 160 with some success. I have a stack of them, so am determined to complete a speaker based around that critical frequency range. Especially since I have several TAD subs sitting around that COULD be used.
Pharos: size of room...my AV room/work area is 21.5' x 22.75" x 9'. So nice size. The other room I might take them to if they turn out to be a great success is 23'x35' with a sloping ceiling from 8' up to 12' or so.
The ESS is typically around 100db or slightly higher efficiency too, as you know. The Klipsch people like to double them up so they can cross at 600hz or even lower. No way am I going to do that. Right now I'm crossing at 800, and they play very loud, and sound great.
Fedde: Thanks for the comment on that 6". I rather like the idea of trying something in that range. A friend suggested the older Audax PR17MO,which is a well behaved driver, and whose efficiency matches up really well. Lots of good choices there. I might be tempted to try something, because they could always be used on another project if the decision was made to go straight from the TAD to the ESS. By the way, I've been to Eindhoven on business.
The weak link for my project is likely trying to get these drivers to play nice with the new (on my shelf) 92db/watt 15" woofers. The frequency range is fine, but it would lag a lot in efficiency. This is all active though.
My cabinet maker is finishing up my latest housing project this coming week, so I'm hot to make a decision while he is available.
In most of the ESS designs the Heil is always attenuated, the woofers being about 90 or 91, and it is usual to attenuate a tweeter down to a woofer's sensitivity.
In their designs I've seen 800, 900, and 1k Xovers. Mine is at 1.8k.
I've got an insertion loss attenuator of high quality WW 9W glass resistors, followed by a 25W pot giving a range of 5dB, and with a switch allowing another cut of 5dB, so a result of 10dB adjustable. My room is about 17 by 36 with a small inset in width at the back, working down the length, and they go loud enough, but I don't want more than 90 ish.
There always was a concern with the original ESS woofers that there was a step in sound resulting in a lack of integration between the Heil and the midwoofer, and that the latter was slow, but a controlled breakup woofer is usually made form a heavier (poly) material because it damps the (controlled) breakup.
In their designs I've seen 800, 900, and 1k Xovers. Mine is at 1.8k.
I've got an insertion loss attenuator of high quality WW 9W glass resistors, followed by a 25W pot giving a range of 5dB, and with a switch allowing another cut of 5dB, so a result of 10dB adjustable. My room is about 17 by 36 with a small inset in width at the back, working down the length, and they go loud enough, but I don't want more than 90 ish.
There always was a concern with the original ESS woofers that there was a step in sound resulting in a lack of integration between the Heil and the midwoofer, and that the latter was slow, but a controlled breakup woofer is usually made form a heavier (poly) material because it damps the (controlled) breakup.
I use a 4.7 ohm resistor in serie with the AMT. It brings it down a bit more than 6 dB and gets it to 8 ohm. I use a Fusion plate amp. Efficiency of 6nd430 is ok, and it is low distortion. I would advise to use a mid that can go down to 200-300 Hz, for an easy match with a big woofer. The new Textreme Satori mids may work well also here...
ESS Heil
Pharos: I've not heard of a glass resistor. Will have to read up on that. I appreciate your comments on your system, and what the factory has done in the past. It is very helpful to have some guidelines. I'm going to move forward this coming week with the mid-bass modules by just building a simple, but well constructed box in the 1.5 to 2.0 cubic foot range. Also have some super heavy 3/4" thick cardboard tubes sitting on the shelf that would work, but would not give the ESS anything flat to sit on.
Using my 24db per octave active crossover, do you think this will give me enough overlap? I know that the 12 " TAD mid-bass will play up to at least 1200, but I intend to cross to the ESS at 800.
fedde: I have a pair of old NHT bookshelf speakers where the surround on one woofer wore out. The cabinets are in perfect condition, and were boxed up to fix sometime in the future. They would make a super easy, free option to jig up a test for an upper mid-range driver, as long as the woofer cutout works. I'll look into that.
Pharos: I've not heard of a glass resistor. Will have to read up on that. I appreciate your comments on your system, and what the factory has done in the past. It is very helpful to have some guidelines. I'm going to move forward this coming week with the mid-bass modules by just building a simple, but well constructed box in the 1.5 to 2.0 cubic foot range. Also have some super heavy 3/4" thick cardboard tubes sitting on the shelf that would work, but would not give the ESS anything flat to sit on.
Using my 24db per octave active crossover, do you think this will give me enough overlap? I know that the 12 " TAD mid-bass will play up to at least 1200, but I intend to cross to the ESS at 800.
fedde: I have a pair of old NHT bookshelf speakers where the surround on one woofer wore out. The cabinets are in perfect condition, and were boxed up to fix sometime in the future. They would make a super easy, free option to jig up a test for an upper mid-range driver, as long as the woofer cutout works. I'll look into that.
The Xover type and resulting slopes and overlap area is a moot question. I suppose it depends on what is most offensive to the listener. Phase is also a consideration, LR4 being widely used, although it has transient problems.
In the extreme a sharp Xoxer will give a 'jump' at the Xover frequency on an arpeggio piano run for example, less pronounced on a shallower Xover where it will blend.
But the compromises are often to do with optimisation of the drivers' best performance areas.
In the extreme a sharp Xoxer will give a 'jump' at the Xover frequency on an arpeggio piano run for example, less pronounced on a shallower Xover where it will blend.
But the compromises are often to do with optimisation of the drivers' best performance areas.
The Heil is almost a fully resistive impedance, except minor foil resonances at 300 and 500 Hz. So I do not understand what L pad or damping could bring... but I could be wrong about this...
I use my AMT with 2nd order bessel HPF at 1200 Hz combined with electrical first order HPF at 400 Hz. The Heil AMT can handle this, at least for my living room size. I use the Harsch XO principle for lower phase shift, you can find a thread on this on Diyaudio.
The two benefits I described; better for the amp, and better damping of the Heil diaphragm.
"I use my AMT with 2nd order bessel HPF at 1200 Hz combined with electrical first order HPF at 400 Hz. The Heil AMT can handle this, at least for my living room size. I use the Harsch XO principle for lower phase shift, you can find a thread on this on Diyaudio. "
The Heil notoriously does not like being driven low, and so is often filtered with a steep HPF.
For "glass" resistor read vitreous as in Welwyn.
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The impedance of ESS AMT is about 3.8 ohm. A series resistor of 4.7 ohm more than halves the level. I presume you would propose to use something like a 2 ohm in series and 4 ohm in parallel L pad config? Which would result in roughly 4 ohm impedance seen by amp and a similar attenuation...
The 1200 Hz crossover is a compromise. I think I like the AMT more than the mid in the 1200-2000 Hz range. It is very fast and detailed. Perhaps 1400 or 1500 Hz crossover could be better, I could try it...
The 1200 Hz crossover is a compromise. I think I like the AMT more than the mid in the 1200-2000 Hz range. It is very fast and detailed. Perhaps 1400 or 1500 Hz crossover could be better, I could try it...
Yes, mine were 3.6,
I ended up after numerous iterations and calculations using a vertical stack top to bottom of; 3.1 above 2.7 above 15 ohms to ground. Then a switch wiper flopped between the two ends of the 3.1, and the other end was connected to a 4.7 pot above a 10 to ground.
The 10 was achieved with a 3.9 in // with a 15. The 10 was achieved with a 18 in // with a 22.
The switch gave a -5dB cut, and the pot a 5dB range.
Although the Heil will go lower, I thought that 1800 was the best place especially because I know that the mid/woofer I used was used by the BBC to cross at 1800.
I ended up after numerous iterations and calculations using a vertical stack top to bottom of; 3.1 above 2.7 above 15 ohms to ground. Then a switch wiper flopped between the two ends of the 3.1, and the other end was connected to a 4.7 pot above a 10 to ground.
The 10 was achieved with a 3.9 in // with a 15. The 10 was achieved with a 18 in // with a 22.
The switch gave a -5dB cut, and the pot a 5dB range.
Although the Heil will go lower, I thought that 1800 was the best place especially because I know that the mid/woofer I used was used by the BBC to cross at 1800.
Are you running the first gen. Heil ?
There is a big difference on the low end performance for the first generation and the latest Heil design.
I can only agree with 1800Hz as a sensible xover for 1st. gen.
But the latest revision reach 800Hz with decent linearity,
I cut between 900-1k, LR4, but that is more of a load concern.
My childhood learning was that you get peak on BW not on LR
It would have been welcome with a lift as the woofer edge surround resonance matches up with a dip on the ESS. However that is accommodated for in the PEQ. Anyway the woofers are with Bessel LP in the current IIR config.
LR4 HP & LP previously in a FIR implementation with correction for linear phase.
Running miniDSP I also manage the gain without passive components. Only external component exception; a coil on lower woofer - but that is primarily for the impact on Qts for low end performance.
So what I am trying to say is that, choosing the right woofer, even a 15" will match up nicely to the Heil. Also when it comes to dynamics.
The only argument I could see for making a 3 way design would be if the criteria is to reuse something already at hand - or if an overall improvement in dispersion is the goal.
In my design I will get problems if going for higher than 1200Hz xover freq. due to baffle layout constraints. Tolvan Edge is a helpful tool on those considerations.
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I only described the attenuator part of the Xover, which is LR4 for the Heil and 1st order for the mid/woofer. (See large coil).
The pot I used was really serious, £25 each in '02, and rated at 25W, my not feeling confident about going active in case I messed up and ruined the boxes.
I had little money at that time and not much in facilities.
Norgaard:
I do not know which Mk the Heil is, it is from '81 AMT 1Bs, but is later than the ones in planet10's which have a forward right angled moulding part as shown. I had one of these in the 80s and cut it off to match the other, the later version. They were as above plated, and I bought the newer 'wedding veil' diaphragms for them.
You are obviously more advanced than I on speaker design planet10, but I am not at all sure about a 15" unit with the heil, as said previously there are many criticisms of the mismatch between the heil and ESS's 12"woofers. The ESS Rock Monitor used an intermediate between the two, 8" I believe.
My current ones were black painted, but not with the moulding shown on the ESS website which has a slight flare at the bottom, and thicker and fewer plates.
I do not know which Mk the Heil is, it is from '81 AMT 1Bs, but is later than the ones in planet10's which have a forward right angled moulding part as shown. I had one of these in the 80s and cut it off to match the other, the later version. They were as above plated, and I bought the newer 'wedding veil' diaphragms for them.
You are obviously more advanced than I on speaker design planet10, but I am not at all sure about a 15" unit with the heil, as said previously there are many criticisms of the mismatch between the heil and ESS's 12"woofers. The ESS Rock Monitor used an intermediate between the two, 8" I believe.
My current ones were black painted, but not with the moulding shown on the ESS website which has a slight flare at the bottom, and thicker and fewer plates.
Another slow progress. First two parts of the horn are ready to be cut from 30 mm XPS foam board, the CNC is ready and tested, I am waiting for delivery of the dust extraction system. I do not want to have XPS particles all over the room and I do not want to stand for two hours at the CNC with a vacuum cleaner in my hand
