DIY Flat Panel Speaker Love

[Unbiasedsound]

Thanks so much for the quick replies. The reason I had settled on the 12 x 12 in the 1/4" thickness is from advice you had given Listencarefully a few pages back when he had built a pair. So, it appears you have done additional testing and found the 1/2" thickness in a narrower width is advantageous over a 12 x 12? One would think such a small panel in that thickness would have zero flex and would instead act as a solid piston up until wavelength became shorter than it's width but maybe that provides an improved acoustic performance.

Have you built a few of these and is definitely your preference for a mid that can reach down to 150 hz up through the normal upper mid frequencies?

It will be so much easier to access the 1/2" EPS compared to the 1/4!

Are you still advising the 2lb density with a thicker, smaller panel? Or will a lesser density suffice?

Last question. Are you still suggesting the TEAX19C01-8 exciter for these small panels?

My apology for the multiple questions but want to get this right!

Thanks,
Allen

I explained on post #1392 and 1394 in more detail of why I changed my panels design. Its because you cant defy physics as DML's are very similar to conventional cone drivers. Less flex (stiffer)=better highs while more flex= better bass so you have to find a balance.

3 major factors that effect the frequency response of DML panels.

1. Type and size of exciter used as larger exciters have more bass while smaller exciters have better highs but less bass. This is physics and was explained in earlier post.

2. Density of panel as the higher the density the better the high frequencies while lower densities will produce more bass but less highs.

3. Size of panel as larger panels will produce more bass but the higher frequencies will suffer while smaller panels will produce less bass but better high frequency response.

There are usually compromises when using a full range driver and you have to find the right balance for your application.

2-3lbs of density with 1/2 thickness. Higher (4-5lbs) the density the better the high frequencies BUT the higher the density the less efficient they become due to being to dense. Again you have to make compromises. What works for my design might not work for your design.

Oh yes most def. the TEAX19C01-8 is the best when it comes to balance of highs, mids and bass as this is my go to exciter for all my designs. I dont like to mention this because P.E will raise the price. LOL

[allenb]

There are 1/4 thickness on ebay but I prefer the 1/2 over 1/4 as the 1/2 sounds more full while the 1/4 sounds more thin. As for the width of the panel 12 inches is too wide/large..... A small panels ideal width should be around 5-8 inches give or take a few inches, while the height can be the same and or at max double the width. This is the reason I recommended the 6X10X1/2 EPS.

Also ideal DML panel height placement when you are sitting down is below ear level. DML's have very wide dispersion patterns so if the panel is to tall the high frequencies tend to go over your head.

To many people watch Tech Ingredients vids and think that there panels should be placed higher up above ear level which is not the ideal height placement.

Thanks so much for the quick replies. The reason I had settled on the 12 x 12 in the 1/4" thickness is from advice you had given Listencarefully a few pages back when he had built a pair. So, it appears you have done additional testing and found the 1/2" thickness in a narrower width is advantageous over a 12 x 12? One would think such a small panel in that thickness would have zero flex and would instead act as a solid piston up until wavelength became shorter than it's width but maybe that provides an improved acoustic performance.

Have you built a few of these and is definitely your preference for a mid that can reach down to 150 hz up through the normal upper mid frequencies?

It will be so much easier to access the 1/2" EPS compared to the 1/4!

Are you still advising the 2lb density with a thicker, smaller panel? Or will a lesser density suffice?

Last question. Are you still suggesting the TEAX19C01-8 exciter for these small panels?

My apology for the multiple questions but want to get this right!

Thanks,
Allen

[Unbiasedsound]

There are 1/4 thickness on ebay but I prefer the 1/2 over 1/4 as the 1/2 sounds more full while the 1/4 sounds more thin. As for the width of the panel 12 inches is too wide/large..... A small panels ideal width should be around 5-8 inches give or take a few inches, while the height can be the same and or at max double the width. This is the reason I recommended the 6X10X1/2 EPS.

Also ideal DML panel height placement when you are sitting down is below ear level. DML's have very wide dispersion patterns so if the panel is to tall the high frequencies tend to go over your head.

To many people watch Tech Ingredients vids and think that there panels should be placed higher up above ear level which is not the ideal height placement.

[allenb]

Styrofoam Sheets (6" X 10" X 1/2") - Craft Quality Sheets | eBay

Smaller panels are better suited for mids and highs and since you are using a pair of 8inch woofers you dont have to worry about the low end.

Although there will be a difference the benefits are subjective to your personal preference. Its basically about dispersion.

I agree entirely on small versus large panels. I'm looking for the 150 hz - 8K range. I'm shooting for a 12" x 12" x 1/4" panel and can cut larger panels down to the 12x12 but can't hot wire cut the thickness down which would be needed if using the source you linked to. Do you know of any sources who can sell small quantities of the 1/4" thickness in the higher densities?

[Unbiasedsound]

Styrofoam Sheets (6" X 10" X 1/2") - Craft Quality Sheets | eBay

Smaller panels are better suited for mids and highs and since you are using a pair of 8inch woofers you dont have to worry about the low end.

Although there will be a difference the benefits are subjective to your personal preference. Its basically about dispersion.

[allenb]

Hi everyone. New member here. I've read all of the thread and lots of great info here.
I'm building a pair of open baffle using a pair of 8" woofers for low end and want to build something similar to the Bertagni SM80's in a 12x12 for mid-hi. Will experiment with adding extended hi range after giving a listen.

A couple of questions. I've had no luck finding a source for the 1/4" eps in 2lb or anything in that range but did see a reference to a UK source. Can someone shoot me some possibilities for higher density eps here in the states? Ebay turned up nothing either but maybe was not searching with correct wording.

The open baffle wings will be 8" deep from floor to top of enclosure. Do you see any huge benefit in stopping the wings where the 12x12s will reside?

Thanks,
Allen

[Unbiasedsound]

The Z standard cap on the 2nd order low pass made a difference as its now smoother and more neutral then the dayton cap.

[DeZZar]

I've used the Jantzen cross cap on the woofer circuit before and can't complain. I'm going to try the Standard Z next time.

[Unbiasedsound]

For my DML panels the best capacitor is the Jantzen Z standard over the Theta and Dayton film and foil caps.

Theta is clear and detailed but gives out ear fatigue. Maybe a boosted top end?

Dayton film and foil is sounds very open but has a lot of sibilance and or what some might call air? DML's have a lot of sibilance to begin with so more is not needed especially for my taste.

The Jantzen Z standard is more neutral/smooth sounding with way less sibilance then both caps mentioned above. I guess it comes down to personal taste as some people like sibilance.

Also some people mentioned that ones speakers must be very revealing in order to hear differences in capacitors and DML's are very revealing to begin with and even more so if built/designed right.

[Unbiasedsound]

On the DIY forum some members were saying that in a low pass second order Xover that a higher end cap wont make any difference. I was thinking of changing the datyon cap to a Jantzen cap of the same value in my second order low pass to see if it actually makes a difference.

[DeZZar]

Yeah the old law of diminishing returns kicks in fast! You start to only get very small incremental gains (if any) the further you go. And honestly I do have the type of overall system that has the resolution to find those last few percent so I just try and keep the parts selection within a cost that's reasonable for the overall speaker.

[Unbiasedsound]

I totally get what you are saying. Although I havent tried many caps what I've noticed from all the caps I have tried is that they IMO "COLOR" the sound for better or for worse. In my DML designs I prefer the colored sound of the Jantzen Z standard as they help smooth out the shout and sibilance from my DML panels combined with the Audiocap Theta smoothing it out even more but adding extra detail. So I guess it comes down to each individual design as well as other factors like you mentioned and of course personal preference.

The Dayton poly/metal caps (DMPC/PMPC dont suit my DML designs very well as they can sound a tad bit sharp/harsh/grainny on certain vocals and instruments. I just tested the Dayton DFFC film and foil caps and they are much more suitable to my liking as they smooth out the sharp/harsh/grainny sound of my DML panels. The difference IMO of the Dayton film and foil and the Audiocap Theta is the Theta is clearer with more detail but it cost almost 7 times the price of the Daytons but its not 7 times better. lol

[DeZZar]

OMG. Anyone that says they cant tell the difference between NPE and all other higher end caps must be smoking crack or deaf as heck. LOL

Yeah it all boils down to the overall quality of the system from source all the way to room. Someone running cheap drivers with museum grade nostalgia amplification streaming spotify out the headphone jack of their phone won't hear a difference (most likely).

Now I am wondering just how those Jantzen Alumen foil Z caps would sound like compared to the Audiocap theta? Or the Jantzen Z superior or Silver? Maybe later down the road.

In theory as the caps get better they simply get closer to sounding like there isn't a cap at all. The best cap is no cap.

[Unbiasedsound]

My P.E. package worth of $140.00 in capacitors have arrived today. I upgraded from a combination of NPE/Jantzen standard to Jantzen Standard/Audiocap Theta and OMG. Anyone that says they cant tell the difference between NPE and all other higher end caps must be smoking crack or deaf as heck. LOL

The Jantzen S/Theta cap combo OMG just took my DML panels to a whole another level. It took away the shout/harsh/grainess/sibilance and gave out more clarity and detail. I hear subtle details in tracks I am familiar with that I've havent noticed before. I dont think I could ever go back to NPE. I did buy some Dayton film foil but havent tested them out yet but will soon once I have more time. Only down fall is the cost. The theta cap cost around 4 times the price of the exciters I use and in fact is the most expensive part of my DML panels. LOL

I was skeptical at first because of the price of those expensive caps and some mixed reviews but I guess you do get what you pay for when buying those expensive caps. Now I am wondering just how those Jantzen Alumen foil Z caps would sound like compared to the Audiocap theta? Or the Jantzen Z superior or Silver? Maybe later down the road.

[Unbiasedsound]

As I mentioned before if you look at all the BMR drivers none of them are larger then 3.5 inches. Why? because once the diaphragm starts getting larger the more the high frequencies will suffer. The smaller the driver the better the high frequency because at that small size only the high frequencies are being produced due to physics. Once the diaphragm starts getting larger it will produce more midrange frequencies. If it gets even larger then midbass then bass then sub bass the larger it becomes. If Tectonic made a 6,1/2inch BMR driver it would no longer be classified as full range but rather a mid/woofer or wide band in which it would have to be coupled to a tweeter with crossover as a 2 way design like Phase Technology speakers which use a flat BMR like driver for the mid/bass and a 1inch dome tweeter for the highs. Even Sony and Technics made a BMR type of speaker with there APM series of flat diaphragm speakers that utilized a tweeter and mid/woofer or tweeter, midrange and woofer. Like I said BMR technology is nothing new.

Phase Technology - YouTube


Sony APM-77W exclusive design by Oldplayer.ru (винтаж аудио) - YouTube




TECHNICS SU-A6 SE-A5 & Technics SB-M2 тест Oldplayer - YouTube