My friend bought me a new digital amp , which he thinks sounds fantastic.
He has bought a lot of these , as they are very cheap .
I have no complaints so far , and sounds very similar to my digital amp.
Then he asked me to wire up this 3.7watt digital amp for him( second picture), which he also thinks has a fantastic sound.
I should have known it wouldn't be a free gift 😄
He is really into low wattage amps, even though he has some very expensive powerful amps.
He says he pushes then quite hard and upsets the neighbours.
He is now talking of building some eps panels to get a lot more volume out of the amps.
I'm glad I don't live next door to him.
Steve.
He has bought a lot of these , as they are very cheap .
I have no complaints so far , and sounds very similar to my digital amp.
Then he asked me to wire up this 3.7watt digital amp for him( second picture), which he also thinks has a fantastic sound.
I should have known it wouldn't be a free gift 😄
He is really into low wattage amps, even though he has some very expensive powerful amps.
He says he pushes then quite hard and upsets the neighbours.
He is now talking of building some eps panels to get a lot more volume out of the amps.
I'm glad I don't live next door to him.
Steve.
Attachments
Hello André
Might it be possible to have a measurement of the exciter parameters before and after? Is there a change in the compliance or damping? I imagine the role of the compliance to the bass, don't see for the top end...
Christian
I thought that my muse digital amp was small 😄
Yesterday I was listening to my canvas panels with cling film on.
And have come to the conclusion that I need to build identical panels to test the difference between the film Coating and without.
I came to the conclusion that there was definitely more detail and output with the film passive layer.
I need to find out if it is better to cover the whole panel or just the central area ?
Or does it make a difference?
And the distance or air gap between the two surfaces?
You get a free electrostatic or planar panel without the magnets.
The back of the panel is still dml, but what would the front of the panel be if a thin film is covering the whole surface?
Sound would still come through the film but also the film has its own sound output.
Is it still dml or does it act as a planar panel ?
Interesting 🤔
There goes another patent 😫😭😁
Steve.
Yesterday I was listening to my canvas panels with cling film on.
And have come to the conclusion that I need to build identical panels to test the difference between the film Coating and without.
I came to the conclusion that there was definitely more detail and output with the film passive layer.
I need to find out if it is better to cover the whole panel or just the central area ?
Or does it make a difference?
And the distance or air gap between the two surfaces?
You get a free electrostatic or planar panel without the magnets.
The back of the panel is still dml, but what would the front of the panel be if a thin film is covering the whole surface?
Sound would still come through the film but also the film has its own sound output.
Is it still dml or does it act as a planar panel ?
Interesting 🤔
There goes another patent 😫😭😁
Steve.
Attachments
Those are heavy croc clips, and very lightweight wires, 0.5mm copper. And all of the drivers are out of phase with the drivers next to them, so the panel buckles too. I'd be quite amazed if they did not wobble!
But, of course, if the wires were rigidly mounted with low frequency signals and massive magnet movements like that, then something will break either in the wire where the solder stops. Or on the solder terminals themselves.
Keep in mind that I'm using these drivers for high power audio. I'm not just tickling them with hi-fi signals, I'm running them to their limits and sometimes beyond.
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Thanks Christian,
I've been keeping track of the FR. But I did not think of tracking the TS parameters too. I've got a few MegaBass drivers that are still not broken in properly. So I'll measure TSP's on them before running them in, and then measure again afterwards.
Pretty sure he's referring to the motor being attached to a spine, not the wires.
Y
The thing is in this specific case, that we are trying to get the magnet/VC interface to move as much as possible without impinging on the VC.
Indeed. Maybe something got lost in translation.
The thing is in this specific case, that we are trying to get the magnet/VC interface to move as much as possible without impinging on the VC.
Andre.
I am still pondering on which exciter to get for the proplex panels.
They need to be able to drive a heavy panel with full frequency response.
The 25FHE 4 seems to be at a good price at the moment, but am wondering how many I would need per panel to drive the proplex panels in a domestic environment ?
Steve.
I am still pondering on which exciter to get for the proplex panels.
They need to be able to drive a heavy panel with full frequency response.
The 25FHE 4 seems to be at a good price at the moment, but am wondering how many I would need per panel to drive the proplex panels in a domestic environment ?
Steve.
Steve I'm unfamiliar with this driver except that its inductance and coil size seem to contradict the response curves advertised by Dayton. I will be ordering a few of these soon, and will test them when they arrive.
I'm also unfamiliar with proplex or heavy panels.
But it seems that some of the guys on the forum have driven plywood panels with a single 32EP-4 Thruster, and have achieved good results?
If you can generate a white noise signal, and get live RTA, then you can move the drivers all over the panels until you find the sweetspot with good HF.
I don't think multiple drivers increase HF by default. Their positions must be carefully chosen. Dayton has a good article on this.
Still, as helpful as the article might be, I find that I still go the white noise/RTA route, and hardly ever end up with the same positions as recommended by the manufacturer. 🤷♀️🤷♂️
I sure hope you guys get some of these FHE25 4 exciters. They are what I use for my builds and look forward to what you think of them. They are very strong and give me what I want in mids and highs as I go the sub route for lows.
I would find it hard to believe there's a better bang for the buck out there.
I would find it hard to believe there's a better bang for the buck out there.
toddincabo.
i am waiting to hear the results of my 10watt exciters before deciding how many fhe25-4 i need.
in the meantime i did a recording of my canvas panels with cling film on the front surface.
they have plenty of detail and sound very nice.
the exciters are not braced at the back yet, so hopefully i will be able to turn them up a bit more, but i think they are good enough to let my friend have a listen to them and see what he thinks.
if he likes them i can build him something more to his needs, he has not a clue what to expect as yet.
steve.
i am waiting to hear the results of my 10watt exciters before deciding how many fhe25-4 i need.
in the meantime i did a recording of my canvas panels with cling film on the front surface.
they have plenty of detail and sound very nice.
the exciters are not braced at the back yet, so hopefully i will be able to turn them up a bit more, but i think they are good enough to let my friend have a listen to them and see what he thinks.
if he likes them i can build him something more to his needs, he has not a clue what to expect as yet.
steve.
I re-read your post and it started me thinking.
I originally thought that a dml panel would be good for acoustic guitars as it would recreate the sound of the acoustic guitar perfectly.
I did not think that the guitarist would want to change the sound using a box speaker ?
Although I would think that dsp could change a dml panel to sound as they wished?
I have ,since you mentioned the 5k limit on guitars, noticed guitar recordings with responses going up to 10k, this of course includes banging and scraping of the guitar and strings.
Are these recordings made differently without the speaker box amp ?
I am definitely going to have to talk to my friend about this, and maybe sort something out, if he thinks it is desirable?
Steve.
My post before this said:
"... acoustic and electrics both have audible information below 100hz and well over 5kHz,..."
If you put a 5khz 2nd-order low-pass filter onto a flat-response speaker-amp combination, then anything at 10khz would be only 6dB down which is still plenty audible.
This is also why I imply that a DML panel does not need any filtering. It's probably already much more than 6db down at 10kHz compared to its mid range.
That's the first thing.
The second is that the highest fundamental note on a guitar (electric or acoustic) is around 1200hz or a bit more. You'd probably want to hear at least the 4th or 5th harmonic (4 x 1,200hz=4,800hz, or 5 x 1,200=6,000Hz) to be able to identify it as a guitar and not, for example, a piccolo. But not only that, you want to hear the sounds above that frequency which give character to the sound. In the case of a close-miked acoustic guitar, yes, one definitely wants to hear fret noise, finger slides, and the plectrum or the fingernails on the strings. And the rest of the harmonics. And those are all way above 5kHz.
An electric guitar will probably not require as much definition above, say 5kHz, as many electric-guitar speakers have already broken up below that frequency, and are collapsing at that point. But there are always harmonics and sub-harmonics that need a controlled wide-band response.
I would stick to a 6db/octave roll-off below a coupla-hundred Hz's, plus a smooth +6dbpeak at 3khz or so, and a 6db/oct high-end roll off above 5khz if you have a flat-response system! In other words, if you plug your guitar straight into a mixing-desk/amp/studio-monitor combination, or a hi-fi, then it's going to sound very bad indeed if you do not tailor the EQ.
But dedicated guitar amp/speaker cabinets already have a pre-designed sound, and which is almost always built around the speaker in the cabinet. And that speaker, as-is, shouldn't really need much tweaking at all, even with a flat-response amp.
This is why I suspect that a small, 12"-equivalent surface area DML panel might sound pretty good as-is, without special damping or edge treatment or tweaking or EQ or processing.
I've never tried it, but I will one day.
Hello
Just to share a new impedance measurement.
The quality of the measurement was improved compare to the previous one. Here the source is an USB DAC able to drive low impedance headphone (USB Audiophonics Sabre) that feeds a 100 Ohm resistor (see REW doc). The measures are sent to the line inputs of my old Audigy 2NX with a short shielded cable. The result in noise is just acceptable probably because of the 5V switching supply of the Audigy. The laptop is on its battery.
Below the impedance of one of my 3mm poplar plywood panels. No conclusion from the measurement for now. The goal was to have a set up with less noise and to have a first view of a panel impedance.
Even if the plywood is relatively heavy and damped (not so sure!), there are many "spikes" on the impedance curve where resonances are.
Just to share a new impedance measurement.
The quality of the measurement was improved compare to the previous one. Here the source is an USB DAC able to drive low impedance headphone (USB Audiophonics Sabre) that feeds a 100 Ohm resistor (see REW doc). The measures are sent to the line inputs of my old Audigy 2NX with a short shielded cable. The result in noise is just acceptable probably because of the 5V switching supply of the Audigy. The laptop is on its battery.
Below the impedance of one of my 3mm poplar plywood panels. No conclusion from the measurement for now. The goal was to have a set up with less noise and to have a first view of a panel impedance.
Even if the plywood is relatively heavy and damped (not so sure!), there are many "spikes" on the impedance curve where resonances are.
