Presenting the Trynergy - a full range tractrix synergy.

[Eldam]

The vovlo parts are expensive and it's a gazoline addict ! I find them both cool, but maybe the Van have more fun possibilities

 

[kees52]

The vovlo parts are expensive and it's a gazoline addict ! I find them both cool, but maybe the Van have more fun possibilities

Parts is not expensive a good used automatic 50 euros.

I do put LPG in, do one liter for 7 km.

X I am started again with the faseplug, and then the bass, I think it is better.

rerards

 

[xrk971]

What do you guys think of 2% THD at 114dB? I think that is good isn't it?

 

[Eldam]

I think you changed of mic ?

If I have not the 10F cone flying on my face after a few milli second peak at 114 dB, I will be more than happy 🙂 !

What is the predicted dB efficienty at Xmax( one meter) ?

Good news X, do you confirm it's with 10F and not the Faital ?

 

[weltersys]

Art,
I double checked my measurements and there was a problem with the software on the previous data that used the wrong mic absolute SPL cal. It made the mic measure unusually low, so the speaker is actually more sensitive. I double checked the cal again and did sanity checks with known speaker sensitivities and its all good. Also, I did my estimate of how loud a dance floor is set at about 90dB and that checked. I was wearing earplugs before so had no aural sanity check for mic cal being thrown off.

So it turns out the sensitivity is actually about 100dB at 2.83v at 1.0 m. I set the mic at 1.0 m exactly and on axis. I am using a Fluke 101 DMM to measure the AC voltage applied before the 6.6uF high pass cap.

The distortion stays quite clean, with the worst being a 2% THD at a 2.35kHz peak (most of it is of non-effensive 2nd order).

The horn has some problems with dips due to the lack of a phase plug and cancellation from the large cone trying to act like a compression driver, but distortion wise, it is quite good. I think you were saying if it is less than 10% THD at 114dB, that is a good.

So it turns out, I don't need a big amp to max out my Trynergy - a simple TPA3116D2 with a 19v laptop brick works just fine.

12.41v (mic limit) with cursor on 10kHz - to answer your earlier question what the SPL level at 10kHz is when 1.5k is at 114dB:

Xrk971,

Thanks for performing the tests!
Impressive clean output from a small cone driver, and you were correct, the distortion increased linearly with output.
That is unlike what I found testing HF compression drivers, where a 3 dB increase in level resulted in close to a 6 dB increase in distortion components, an example of a dual tone test at 2 meters below.

A phase plug may prove difficult, as different portions of the cone (probably) produce different frequencies, most of the VHF may only be coming from near the voice coil. Placing the test mic within a few mm of the cone and checking response in various places could help determine what type of a plug may help eliminate the dips. That said, increasing the compression ratio with a phase plug may also increase distortion quite a bit- and you can't equalize distortion out.

Looks like 12.4 volts is still quite a bit lower than the peak levels the Trynergy could achieve, there was only .2 dB power compression evident in the 12.4v test.

Art

 

[xrk971]

I think you changed of mic ?

If I have not the 10F cone flying on my face after a few milli second peak at 114 dB, I will be more than happy 🙂 !

What is the predicted dB efficienty at Xmax( one meter) ?

Good news X, do you confirm it's with 10F and not the Faital ?

This is for 10F/8424, not the Faital 3FE22.

No, same mic but absolute SPL calibration was off in previous data due to software glitch.

With the appropriate high pass filter to limit excursion at low frequencies, the cone loading is so efficient, that the driver is thermally limited to 120dB assuming a -6dB/oct high pass filter at 250Hz. The rated rms continuous power is 30 watts. However, brief transients circa 900W have been demonstrated to be achievable on a TC9FD by others in burst sweep measurements. So I think +3dB or +6dB may be achievable for peaks. I think the 10F, is probably more robust than a TC9FD so should not be a problem to hit brief 126dB peaks (120 watts).

The simulations show that with a 6.6uF cap in series, the max cone displacement is 0.9mm at 12.4 volts. xmax on 10F is about 2.5mm so lots of room to go. Also, using a -12dB/oct or even -24dB/oct active filter at 350Hz would reduce excursion even more.

For example, a -24dB/oct HPF at 350Hz results in only a 52 micrometer displacement in the cone! Microns with a u!!

 

[Eldam]

More than 99% of listeners need !

So no thermal issues with the most dynamics reccording with an average listening volume between 70/80 dB at 3 meters ! We have 30 dB of headroms for the best dynamics reccordings ! Cool ! And still the good sound of the 10F 😎.

The woofs become a challenge...

 

[xrk971]

To keep up with that kind of sensitivity, need pro audio woofers that are about 100dB sensitive at 2.83v. Not hard to do with series parallel qnty 4 x 94dB woofers.

Maybe something like four B&C 8FG51's? Pricey though at $108 ea - but should be able to keep up. Maybe I will simulate them and see...

https://www.parts-express.com/bc-8fg51-8-professional-woofer-8-ohm--294-5911

 

[Eldam]

for me it's too expensive but the design deserves it !

Or finding some drivers like the 91 dB Faital (Can they no hit 114 dB with a High Pass at 100 hZ or 150 hZ !

150 Hz seeming in the litterature to be the limit for hearing the localisation of the sub-woof cabinet (range < 100/150 Hz)

I will try the technic of an enclosure around the horn like Bawslo to have a wider bottom & top horn walls to try to putt 2 x 10" instead 4x6.5" : at equal surface the 10" are cheaper, you may find stiffer surround (coated paper) and more BL to glue to the fastness of the 10F in the horn !

 

[xrk971]

Qnty 2 x B&C 10CL51 may do the trick.

https://www.parts-express.com/bc-10cl51-10-neodymium-woofer--294-693

For 4ohm parallel load you can get 102db at 2.83v and can probably hit 80Hz easily with a bass reflex re-direct port as Weltersys proved in the SynTrippi.

 

[Eldam]

Yeap : the Weltersys ones ! I thinked of something like that as well ! Around 100 euros each : much more better for my pockets ! And if they have a 16 ohms, even better to match 8 ohms...

I'm sensible about those mid-bass frequencies ! Not an easy range to reproduce !

 

[xrk971]

Mini 0.48x scale Trynergy?

Contemplating a scaled down Trynergy for a 2in full range driver. Throat would be 1.38in x 1.38in (0.48x scale from pdf plan). Mouth would be about 12.7in wide x 8.5in tall (pretty compact). I would use qnty 4 x 5.25 polycone buyout woofers and Tang Band W2-852SH as the full range. Overall system sensitivity will be limited by the woofers to 94dB. However, with bass reflex redirect via qnty 4 x 2.0in x 5.5in long vents I can get coverage from 100Hz to 20kHz with 550Hz XO and max system sustained SPL of 113dB.

Here are some initial sims with base sensitivity after padding fullrange by -6dB, system sensitivity at 2.83v.

Cone displacement at xmax for full range (1mm):

Max SPL:

Electrical Power input:

Throat, band-pass port, and BR redirect vent max velocities:

Edit: just realized that the max SPL is really limited by the max thermal input on full range which is 16 watts. If I set high pass filter at higher frequency, I can keep excursion low and boost max SPL on woofer to an overall system max SPL of 116dB when the full range driver hits 16 watts thermal limit. The woofer also happens to hit xmax of 3.5mm at 40 volts required to reach 116dB.

 

[Eldam]

If I remember the 10F cone diameter with suround is 2" while the driver is 4" in itself . the throat has to be littlier than the cone itself ?

Does a single 10" woofer fireing towards two ports has a diameter foot print bigger than 2 x 6.5 " on the top and bottom horns wall ? No one with a low Vas to stay sealed ? a cheap Emminence or faital ?

You mean you need in both horns design (70 % & 48 % scallings) to rise up a little the HP filter of the 10F to allow both a little more output (116 dB) at Xmax while avoiding thermal issues ? The 70 % does not allow more spl at same cone exursions than a littlier horn ?

I'm lost ! In a side I understand the woofs are the limiting factor but in an other side I surmise less cone exursions from the 10F was the key of your good feeling ? Because of the poor BL, should not we stay with the 70% (66% exactly to have 2" throat) design ?

 

[xrk971]

The above sim is for a totally different (new) speaker with a small Tang Band 2in driver and the four 5.25in woofers I recently bought. If you are building the 2in throat version for 10F ignore what I am proposing above.

 

[Eldam]

Great.

 

[thunk303]

Why the interest in smaller horn x? Just size or bandwidth not required?

 

[xrk971]

Size mostly - trying to see if a more portable or WAF'able format is possible.

 

[kees52]

Thermal limit is because of the 6 dB fall of on hf then indeed thermal things are in play, a way to make a nice faseplug will make that a lot easier to get more.

But not yet ready, rain is a problem here and I do sawing outside because of that nasty dust.

regards

 

[xrk971]

If anyone knows of another 2in driver with low Qts let me know. This is about the only one I have come across with circa 0.3 Qts.

 

[kees52]

If anyone knows of another 2in driver with low Qts let me know. This is about the only one I have come across with circa 0.3 Qts.

small drivers has most of the time also low wattage, special voicecoil because of hf shelving almost 12 dB, that is a lot..

finding one is indeed more difficult. a working faseplug can do help.

I go search for you.

regards