Yung Plate Amp - Initial Impressions - Page 2

R8 = 10.05k
R23 = 57.9k

They are great if the boost and hpf work of you. Some better info from PE would have been nice.

But, they are the only true class D plate amp on the market and they do produce good power. Like I said, the 300-6 will find a good home in my living room where I don't care about 20hz and below. It's just not what I want for a HT.

I'm more interested in seeing some results from the non-boost models than the 500. At the price point of the 500 it's better to go pro-amp.

I ordered the 500-6, should be in soon and could take a look. Anyone have a photo of where the resistors are?

You would need a good macro lens to take a picture of the resistors. They are super tiny. Anyway, they are right on the back of the pre-amp board that runs vertically, right next to the LED.

My girl took a pic and measured these out for us. Looks about the same as what you guys measured. This amp is some beef cake weight and quality built. I bought it for a friends sealed infinity sub build.

SD-500-6
Fluke77 meter values

R8 = 9.99k
R23 = 57.6k







edited: ground loop hum is usually eliminated with plate amps because they lack ground in the power outlet. Majority of them are all just two prong (neutral and hot). Pro's have the ground and best to have equipment sharing the same power source to avoid hum. Usually hum is caused by an outside source item fed back into the receiver which then also feeds your amp. Cable boxes being most common. Can find plenty of threads where we discuss this on AVS and ideas on resolving.
Edited by autox320 - 11/30/12 at 9:21pm

Does anyone know if the 30hz filter on the 300 watt Yung plate amp can be defeated?

So it would seem the SD500-6 also has the boost at roughly the same frequency as the SD200-6 and SD300-6.... not at the advertised 25Hz, and not 6dB?

HTS has a thread also btw http://www.hometheatershack.com/forums/diy-subwoofers-general-discussion/63218-notice-yung-subwoofer-plate-amplifers.html#axzz2DtgEQnn4

Hi to all. I just need bit help here. I want to buy the 500w Yung but not sure if getting the +6db version or the normal one. I made a 15" sealed sub around 3cF.. Driver is a Dayton 15"HF. Enclosure is very well braced and with driver weights around 80 pounds. I was using a inuke 3000dsp but the inuke was damaged and meanwhile im using a bash 250w plate from my BicPL200 and guess what? With the 250w bash plate sounds better than my inuke!! And yes, I tried different dsp setups on the inukes....

On description says thst is good the +6 version for sealed subs.

I can get even the 300W version for such cheap price of $99 or the 500w with +6 boost @ 30hz from $129.

Help please
Edited by javygonx - 12/2/12 at 11:13pm

But the boost is higher than advertised, which puts the filter higher as well.... killing some of the low end that the 15" HF is capable of. I sim'd in Jeff Bagby's Woofer Box & Circuit designer 5 with 3.5 cuft. net...

With the Yung (assuming a filter with Fc=30.149Hz, Q=1.2), the -3dB is 31.1Hz, -6dB is 27.1Hz, and -10dB is 23.8Hz. With the Bash 300 instead (default filter Fc=17.7Hz, Q=1.0), -3dB is 30.0Hz, -6dB is 23.8Hz, and -10dB is 19.26Hz.

So the BASH would extend deeper, at the expense of output since you'd have about half the amplifier power. I really don't like how t seems all of the Yung models have the same boost/filter. So I'd take the Bash for the flatter low end... but I don't need the higher output.

BTW, today is last day for the sale on the SD500-6.

Ok; thanks for that. And yes; I dont want the lower frequencies to suffer; so; does adding 200W from Yung-500-6 Plate knowing that will have a significant roll off below 30Hz is still a good option over the 300W Yung with no boost?
I know special ends today; and at least on my tests my Bash 250W moves the 15" pretty well; but Im not an expert; and you guys are more in depth with this...

Too bad there's no test with the Yung with +6dbs on sealed subs vs Yung with no boost on sealed subs!..... At blind eye; I prefer the 500W Yung-No boost model but its quite expensive!; Im thinking in selling my inuke 3000DSP for like $350; completely new; sealed box. Behringer sent me a new one. The old one I had was on warranty. Too bad and Im still wondering why my sub on plate amps sounds so good while on Behringer sounds ok; and I have to power it like 75% on volume on the inuke to get a decent performance; while on the Bash 250W plate at 2'o clock its pretty amazing.

Have to decide today to place this order! .. Hard decision Deeper vs Higher Output!...
Edited by javygonx - 12/3/12 at 9:34am

That's just the differing gain structure between a pro audio amp and a HT plate amp. The iNuke still has more power.

Wow!... Decisions!!... I think I will take the risk and get the 500W with boost version. Im just worried about the roll off due for the +6db boost. If High Pass Filter was around 20Hz then not tha bad; but we are not sure exaclty where is the subsonic filter!!. I will test it and compare with my 250W bash; If I didn't like it then I will return it to Parts Express and get the non boost version!..... Im still reading on other forums. I also have another 15" sub driver; it was custom from PSI. Here is the link: http://psicaraudio.com/products-page/platform-1-subwoofers/15%E2%80%B3-platform-1-subwoofer/

And I can say that this PSI sounds and digs bit deeper than the HT; so maybe the 500W Plate with boost can makes some miracles! .... I tested HT and PSI on iNukel I havent tested the PSI on the 250W Bash yet; I have only 1 enclosure....I love music too; so Im like 60%HT / 40% music. I also have the Emotiva Xref12" and its pretty amazing sub; almost in par with my 15" DIY!.... As for music very tight.

Im almost ready for order; still waiting for more inputs!

On WinISDl Im modeling the driver and I want to add the 6dbs at 30Hz. On parameters there is EQ/Filter so I can add this; but from which of the options? ( Parametric EQ,or Peaking 2nd Order High Pass)? I tried all and in every one I get different plot results; Cone Excursion is what worries me.

For example by selecting Parametric EQ with Center Freq of 30Hz, Gain of 6dbs, Q of 2 it gives me an horrendous plot on Cone Excursion; not good for the driver!!! It overpasses the Xmax by a lot!!... Dayton Reference HT can handle up to 14mm according to specs and the Cone Excursion peak when boosting is around 36mm... Sufficient to damaged the driver!... The Q value default is 2; When Q=1 the graphics looks more smooth. How do I know what Q value is really needed?

When plotting PEaking 2nd order highpass with Peak Mag of 6db and Peak Freq od 25Hz thre's too much roll off. 112db @ 25z; 106db @ 20hz, 96db @ 16Hz.
Edited by javygonx - 12/3/12 at 3:41pm

Check out this page (about halfway down) for info on how to model boost in WinISD:
http://www.subwoofer-builder.com/WinISD.htm

"WinISD takes whatever you set as the System Input Power and then adds the boost. The result of this process must not exceed the maximum power of your system.
This means that the System Input Power must be set lower than the maximum power by an amount equal to the boost."

As you've entered it, WinISD is seeing the total system power as 4x higher than it actually is. Model the driver at 500w with no boost, and again at 125w with 6dB boost and you'll get a better picture of the driver's excursion in that system.

And keep in mind - based on the resistor values of the SD200-6, SD300-6, and SD500-6 provided by members here.... it doesn't look like any of the models have even close to 6dB of boost.
Edited by alphaiii - 12/3/12 at 5:17pm

When modeling an amp like the Yung, I use a peaking 2nd order high pass. And yes, there is going to be a quick rolloff below the boost because the boost is created (as I understand it) by using a high Q high pass filter. This is different than parametric EQ.

Under this situation; sadly I have to skip the 500-6 version and get the 300W non boost version and as always the buyers remorse of the 500-6. *sigh*

According to the subbuilder site you mention above they use PArametric EQ instead of Peaking 2nd order High Pass. I plotted both graphs with Input Power of 125W. Excursion looks much better in that way. Anyway if Parametric EQ is used then the graph doesn't looks too bad at all when adding the +6db @ 30hz and roll off is acceptable; but when using peaking 2nd order high pass; the rollover scares me. Now Im not sure which of the 2 methods are the best fit when performing this kind of tests (Parametric EQ or Peaking 2nd Order High Pass).

Here is the graphs for the Dayton RS15-HF. Yellow lines are "Yung 500W with +6db @ 30Hz. Blue lines are "Yung 300W-non Boost Version". Top grahics are SPL; bottom are Cone Excursion. Non boost version looks smoother!...


Edited by javygonx - 12/4/12 at 9:47am

Everything I've read from others about modeling amps with built in boost like that is to use the peaking 2nd order high pass, or use SOS highpass with user specified Fc and Q.... because the boost is created by using a high Q high pass filter (which is different than PEQ). Your PEQ curves look better below the boost frequency than the peaking 2nd order high pass curves because with PEQ you are not adding in the high pass filter. For the boost models, the Fc of the high pass seems to be around 30Hz, based on reports from users who have traced out the preamp board resistors and calculated the filter based on those values.

Note, in the graphs with +6dB boost, you need to cut the input power to 75W if modeling the 300w amp (ie. divide by 4) to get an idea of the true excursion and SPL with boost (as pointed out in the WinISD link). The SPL at the boost frequency (30Hz) hould be the same as the SPL at that frequency for the the non-boost with a full 300W input power. The 125W input is for modeling a 500W amp with 6dB boost.

Also note, as I already mentioned, the Yung amps don't appear to have a full 6dB of boost... actually don't even appear to have half that much.

And final note - the non-boost models still have a high pass filter, which you are omitting in your WinISD models. Yes non-boost looks smoother, but that's because the high pass is missing. According to a Parts Express rep, the filter roll-off begins at 30Hz, and is -3dB at 21Hz. So it seems the high pass for the non-boost models could be modeled as a SOS high pass with Fc=21Hz and Q=0.707 (a Q of 0.707 means no boost at the filter's corner frequency).

There is more info about these amps here:
http://techtalk.parts-express.com/showthread.php?234409-Yung-or-Bash/page2
and here:
http://www.hometheatershack.com/forums/diy-subwoofers-general-discussion/63218-notice-yung-subwoofer-plate-amplifers.html#axzz2CGhk4jhb

There still seems to be some confusion surrounding where the filter actually is on the non-boost models, and what the boost/frequency actually is on the boost models... but some members have taken the time to trace out the resistors in the preamp board to figured this information out for the boost models (and it's in those threads)... and the best info we have on the non-boost versions is from the PE rep.
Edited by alphaiii - 12/4/12 at 11:00am

I see Alphaiii. Thanks again for the explanation. So, I will plots again the graphs and will add the missing HP filters. Anyway, the PArts Express special is over but who knows if there is another Christmas special soon. By that time I will have enough time in deciding which model to get.
.
And , yes I modeled the 500-6 with a signal input of 125w. I know boost does not reach 6dbs; probably 4dbs. I modeled both. PE claim boost is at 25hz, but studies from garcia and others is at or close to 30hz.

One question on this " SOS high pass with Fc=21Hz and Q=0.707 (a Q of 0.707 means no boost at the filter's corner frequency). So; if there's any boost; where I place it on WinISD? I assume is on Q; but which value? If Q of 0.707 = no boost; then what is Q when boost =1; or 2, etc...?

Thanks again.
Edited by javygonx - 12/4/12 at 12:22pm

If I'm not mistaken, Q=1 would mean no signal attenuation at the filter's Fc, so there would be a slight boost above the Fc to achieve this. This is not to be confused with Q=0.707 having no boost, which means the level would be -3dB at the Fc.

Q=1.4 would be 3dB boost at Fc, and Q=2 would be 6dB boost. This is why I used peaking 2nd order high pass, since you don't need to figure out Q, just provide the frequency and amount of boost.

That's another thank you . I modeled the Yungs with the HPF; and even that the "+6db boost" sounds tempting I will stick with the non boost version. Never heard the difference between both; but if WinISD is correct; then I prefer a smooth and better extension from the non boost version than the boost version. Ricci; some tests here please!