Everything is in the signal path. You use the pot to dial in a value and then replace with a fixed R.
dave
dave
Perhaps it's worth expressing that maybe the price Steve's charging for those drivers is to recoup the R&D time spent, and make a bit of profit etc.. Nothing wrong with making a few bucks from your efforts, and if they perform as claimed maybe a good deal for those in that price category?
Its nice to see everyone interested in pursuing these too.. Dave perhaps you could get them tweaked to close to Steves claimed response too?,that could be a fun process if you had the time and inclination ... Seems like a nice enough base driver to want to take to a new level etc and maybe fill a void in the OB side of things etc..
Now about this Gigaworks thing, where can one buy one of these and are they really good for the money? You really think it's just a repackaged form from Steve?? If that's too touchy of a subject, mods please do your thing... I know my Taboo amp has worked flawlessly and sounds sublime , great purchase and I'm proud to own it.. But you all have the tech minds, I just have my ears and a bit of know how, no where near the many on this forum though, not even close..
Interesting thread, hope it carries on and someone figures out that modded driver 😎
Its nice to see everyone interested in pursuing these too.. Dave perhaps you could get them tweaked to close to Steves claimed response too?,that could be a fun process if you had the time and inclination ... Seems like a nice enough base driver to want to take to a new level etc and maybe fill a void in the OB side of things etc..
Now about this Gigaworks thing, where can one buy one of these and are they really good for the money? You really think it's just a repackaged form from Steve?? If that's too touchy of a subject, mods please do your thing... I know my Taboo amp has worked flawlessly and sounds sublime , great purchase and I'm proud to own it.. But you all have the tech minds, I just have my ears and a bit of know how, no where near the many on this forum though, not even close..
Interesting thread, hope it carries on and someone figures out that modded driver 😎
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At the asking price per pair, I doubt there'll be too many pairs headed Dave's way for 'sperimentation.
To be able to write a description of a product that'll generate a buzz, make people want to try that product is a real talent--
Not slagging Steve's efforts at all, just sayin'
--Looking forward to hearing some user feedback---
Best, Don
To be able to write a description of a product that'll generate a buzz, make people want to try that product is a real talent--
Not slagging Steve's efforts at all, just sayin'
--Looking forward to hearing some user feedback---
Best, Don
Well, the W8-1808 is rated for 30 watts RMS, 60 watts max; the Alpair 12 is rated for 50W RMS; and the Fostex FE208E is rated for 120W nominal. I plan to build Poinz Musical Machine with triode-strapped 6V6GT and a version with 7591As in parallel pentode so it will max out at about 45W RMS. I'll also have a F5 and my vintage Yamaha CR-620 is 35W/ch RMS.
So worst case if I have it really cranked up, the W8s could be maxed out.
I'll agree with you there and the general rule of thumb is a retail price 5X the parts cost. I'm sure most of Steve's customers don't even read or post on diyA. I get that impression just from his forum alone. And his Taboo and Mini Torii amps are highly regarded by friends I trust and share similar tastes with.
We're just more critical here because we have a great group of folks who can cut through the marketing and quickly figure out the reverse engineering. I also think part of the criticism stems from the chosen driver and I suspect he would have received less scrutiny if the driver was a FE208 or Feasterex FC unit.
I know the ZOB speaker was ridiculed to a degree on Joelist too, but I have a set of ZOB cabinets being built by a friend. I found the design intriguing enough to pursue my on DIY set. I guess my ears are just deaf enough not to be bothered by the Helmholtz resonator to make up for the compact size of the speaker. I'll probably try Alpair 12s in the ZOB at some point in the future too as well as experiment more with the width of the baffle and it's height. Steve didn't expand too much on how far he went with baffle sizes when I pressed him for it. I think he tried to make the size as small as possible without great detriment to the sound for higher WAF.
I have a Decware preamp which I'm very happy with. Personally, I have no doubt they perform as claimed. The measurements provided were made with the drivers installed in Decware's Zen Open Baffle speakers in Steve's well treated listening room. I'm not sure how the response would change in other OB designs in other listening rooms. Still, I like the concept.
Cheers,
Alex
Imo, to get the claimed response and considering the curve on the PE site, there is more in the "tuning load" than just a resistor... you could put a "tilt" on that driver and it won't measure like the curve he shows. Flatter, sure, but not like that! He may be doing some things he is not telling you... that's my guess.
_-_-bear
_-_-bear
I was thinking the same thing, but my level of XO knowledge leaves me srtuggling to grook how filters would get reflected thru the transformer.
The 2nd surround will also have an effect, so the filter isn't doing everything.
dave
The 2nd surround will also have an effect, so the filter isn't doing everything.
dave
I feel the pain. I had to do the same thing (funnily ended with about the same width, according to the pictures) and I'm NOT completely satisfied with the bass of my speakers.
Now, I would go at least 10cm larger.
There's a LONG thread about it on the digital line level forum you can see it here:
http://www.diyaudio.com/forums/digital-line-level/137976-experience-diy-dac.html
You can buy the DAC on ebay... somewhere around $130 I think...
Well, the curves aren't apples to apples since the PX curve is the standardized curve for a stock driver and Steve's curve uses his tuned driver in his tuned ZOB. I'm sure he dialed in the tuning load, the slot loading of the Helmholtz resonator and he treats the cones with doping, though Steve doesn't do the full e'NABL'ing process.
The other thing that I realized last night is that I'm sure Steve tried the Gizmo with the Fostex and the TB W8s since he had a W8 in his ZOB when I spoke to him about tweaking internal dimensions for the W8. As much as it pains me to say it since I have the gorgeous pair of W8s Planet 10 did for me, I suspect the Dayton drivers with Steve's cone doping and frame damping came out on top of the ZOB measurement and listening tests. I don't doubt Steve's results, but there are far more tweaks involved than just the iron based LR, but I don't think it involves any additional components than the Gizmo.
What that means for me is that in the end, if I like the overall sound of the ZOBs, then I will probably have Planet 10 e'NABL and mod a pair of them too.
Consider what would happen if you placed one winding of the transformer in series with the speaker as has been posited in this thread but instead leave all other windings disconnected.
So now we start of with an inductor in series with our driver; it's a first order low-pass filter.
If we place a resistance on a winding on said inductor (which now will be called a transformer without losing any of its original inductive characteristics of course) then it will have the effect of a resistance in parallel with the winding which is at the speaker (given mutual inductance). We must consider the effects of leakage inductance (which makes it look more like a series RL network in parallel with the original inductance) but they will be considered quite minimal for typical transformers.
The reflected resistance is of course based on the turns ratio of the transformer and the selected resistance. The effect of course will be to flatten the high frequency response of our low-pass filter as the resistance will become the dominant factor after inductive reactance rises due to increase in frequency.
It can be seen that varying the resistance would produce a flat amplitude variance above the roll-off of the low-pass filter; essentially allowing the remainder of the bandwidth to be introduced or left out at will.
On with the idea: we can put anything we want on the other winding of the series transformer. Any sort of reactive network, nonlinear devices, a tea-kettle... whatever we like.
In the simplest case, if we replace the aforementioned resistor with an inductor we simply end up with the net effect of two inductors in parallel which are then in series with our speaker: a low-pass with a higher roll-off.
Let's now consider a capacitance across the second winding: now we have a resonant tank in series with the speaker AKA a notch filter. It's long been known that a parallel resonant tank in series with a load can be used to attenuate the power level around a particular frequency.
Anything further than the above would just be more complex combinations of R, L, and C components configured to produce the desired response. It's simply a passive filter network.
So now we start of with an inductor in series with our driver; it's a first order low-pass filter.
If we place a resistance on a winding on said inductor (which now will be called a transformer without losing any of its original inductive characteristics of course) then it will have the effect of a resistance in parallel with the winding which is at the speaker (given mutual inductance). We must consider the effects of leakage inductance (which makes it look more like a series RL network in parallel with the original inductance) but they will be considered quite minimal for typical transformers.
The reflected resistance is of course based on the turns ratio of the transformer and the selected resistance. The effect of course will be to flatten the high frequency response of our low-pass filter as the resistance will become the dominant factor after inductive reactance rises due to increase in frequency.
It can be seen that varying the resistance would produce a flat amplitude variance above the roll-off of the low-pass filter; essentially allowing the remainder of the bandwidth to be introduced or left out at will.
On with the idea: we can put anything we want on the other winding of the series transformer. Any sort of reactive network, nonlinear devices, a tea-kettle... whatever we like.
In the simplest case, if we replace the aforementioned resistor with an inductor we simply end up with the net effect of two inductors in parallel which are then in series with our speaker: a low-pass with a higher roll-off.
Let's now consider a capacitance across the second winding: now we have a resonant tank in series with the speaker AKA a notch filter. It's long been known that a parallel resonant tank in series with a load can be used to attenuate the power level around a particular frequency.
Anything further than the above would just be more complex combinations of R, L, and C components configured to produce the desired response. It's simply a passive filter network.
or that his skills at parsing convoluted prose surpass our perception of his technical understanding of what (we think) he thinks is going on?
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