Yung Plate Amp - Initial Impressions - Page 4 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #91 of 120 Old 01-04-2013, 03:37 PM
AVS Special Member
 
Stereodude's Avatar
 
Join Date: Jan 2002
Location: Detroit Metro Area
Posts: 9,726
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 371 Post(s)
Liked: 402
Quote:
Originally Posted by alphaiii View Post

It'll be great to know where the actual filter is on the non-boost versions.
I measured a 500W no boost Yung. R23 = 57.6k and R8=10k.

That gives a Q of 1.2 and a Fc of 30.14Hz. F3 is ~22Hz with a boost of ~2.4dB centered at ~38Hz. Of course this is based on the assumption that the boost circuit isn't also influencing things. I'm somewhat skeptical of this since the components of the boost circuit are populated on the board.
Stereodude is online now  
Sponsored Links
Advertisement
 
post #92 of 120 Old 01-04-2013, 10:16 PM
Advanced Member
 
javygonx's Avatar
 
Join Date: Jul 2010
Location: Puerto Rico
Posts: 904
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
Quote:
Originally Posted by garciab View Post

Yes, something is definitely wrong. Give the amp a good visual inspection to make sure there is nothing touching that shouldn't be, like a couple of components leads shorted, or something touching the metal plate. It's about all you can do. Hope it's something as simple as that.

I inspected the board with a magifying glass for 2 hours and there was no shorts. At least from all things im able to see.
javygonx is offline  
post #93 of 120 Old 01-05-2013, 08:48 AM - Thread Starter
AVS Special Member
 
garciab's Avatar
 
Join Date: Aug 2001
Location: Princeton, TX - USA
Posts: 1,033
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 28
Quote:
Originally Posted by Stereodude View Post

So, does the supposedly boost free version still need C13 and C14 of the boost circuit shorted in order to get a flat response controlled only by R8 and R23?

My recommendation is 'yes'. I'll trace my 300W non-boost version to be sure. I suspect it will still have a boost circuit, but the boost will be so attenuated that it will not affect the stock HPF. However, if one modifies the HPF, the little boost may still have an effect on the FR. Best to know for sure that the boost circuit will have no effects on the FR that you are trying to achieve.

bg
garciab is offline  
post #94 of 120 Old 01-05-2013, 08:54 AM - Thread Starter
AVS Special Member
 
garciab's Avatar
 
Join Date: Aug 2001
Location: Princeton, TX - USA
Posts: 1,033
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 28
Quote:
Originally Posted by Stereodude View Post

I measured a 500W no boost Yung. R23 = 57.6k and R8=10k.
That gives a Q of 1.2 and a Fc of 30.14Hz. F3 is ~22Hz with a boost of ~2.4dB centered at ~38Hz. Of course this is based on the assumption that the boost circuit isn't also influencing things. I'm somewhat skeptical of this since the components of the boost circuit are populated on the board.

This confirms that all of the PE Yung amps share the same HPF. And they all do have some type of boost. On the non-boost models, I believe the boost is so attenuated that it won't provide much boost at all. But no way to be sure until the signal is traced. I traced this on my CSS 500W, and that was the case. But on that amp, the boost actually helps the boost frequency of the HPF (around 34Hz). It was a huge difference in boost amount between the CSS 500W and the PE 200-6, so I don't believe the CSS is considered a boost model.

bg
garciab is offline  
post #95 of 120 Old 01-05-2013, 08:56 AM - Thread Starter
AVS Special Member
 
garciab's Avatar
 
Join Date: Aug 2001
Location: Princeton, TX - USA
Posts: 1,033
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 28
Quote:
Originally Posted by javygonx View Post

I inspected the board with a magifying glass for 2 hours and there was no shorts. At least from all things im able to see.

Well that's unfortunate. Hopefully you'll be able to resolve the problem with the seller or through PE.

bg
garciab is offline  
post #96 of 120 Old 01-05-2013, 06:55 PM
Advanced Member
 
javygonx's Avatar
 
Join Date: Jul 2010
Location: Puerto Rico
Posts: 904
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
I hope so too. Sd300 is on backorder until march. As soon as the seller send me back the money I think I will place an order and get the boosted version frown.gif
javygonx is offline  
post #97 of 120 Old 02-16-2013, 07:29 AM
Newbie
 
ZUes101's Avatar
 
Join Date: Jan 2013
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I own the Yung 500-6 model i already bypassed the Bass boost circuit but i don't know what resistors i need to use to change the HPF to something like Fc of 20 or 19 if anyone can help .
ZUes101 is offline  
post #98 of 120 Old 02-16-2013, 08:16 AM - Thread Starter
AVS Special Member
 
garciab's Avatar
 
Join Date: Aug 2001
Location: Princeton, TX - USA
Posts: 1,033
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 28
For Fc of 20Hz, q of .7, R8 = 25K, R23 = 50K

For Fc of 18Hz, q of .7, R8 = 28K, R23 = 56K

Notice the ratio of 1:2 for a Q of .7, which is maximally flat response. And you can see what happens to Fc as the resistor values increase.

bg
garciab is offline  
post #99 of 120 Old 02-16-2013, 08:50 AM
Advanced Member
 
javygonx's Avatar
 
Join Date: Jul 2010
Location: Puerto Rico
Posts: 904
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
One question. Dont you like the +6db boost? Im just trying to collect info to make sure which Yung model get; if the boosted or non-boosted. Im inclining more in the non boosted version; but want to know your thoughts..
Thanks
javygonx is offline  
post #100 of 120 Old 02-17-2013, 05:53 AM
Newbie
 
ZUes101's Avatar
 
Join Date: Jan 2013
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
thanks for your help garciab as for
Quote:
Originally Posted by javygonx View Post

One question. Dont you like the +6db boost? Im just trying to collect info to make sure which Yung model get; if the boosted or non-boosted. Im inclining more in the non boosted version; but want to know your thoughts..
Thanks

No I didn't like the bass boost it overexurted my sub caused allot of distorsion but as soon as I bypassed the bass boost everything sounded allot better. if I were u I'd get the boosted model and bypass the bass boost its a five minute job and u save a bit of money.
ZUes101 is offline  
post #101 of 120 Old 02-17-2013, 07:27 AM
Advanced Member
 
javygonx's Avatar
 
Join Date: Jul 2010
Location: Puerto Rico
Posts: 904
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
Oh wow. Thats interesting. But I have no idea how to do it. Would be nice to add pics and explain how to do it.
Thank you.
javygonx is offline  
post #102 of 120 Old 02-17-2013, 08:15 AM
Newbie
 
ZUes101's Avatar
 
Join Date: Jan 2013
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
garciab already explained how to do this.
Quote:
Originally Posted by garciab View Post

So here is a wrap up regarding the frequency response of this line of amps. We know that all the boost models share the same HPF (subsonic, rumble filter, etc), and it is set at 30Hz with a little boost above that. We also know that there is a seperate bass boost circuit to give the boost that is spec'd for each model. The HPF and boost are summed (combined) to give the overall frequency response (plus the phase and low-pass adjustments of course). So for those still interested in these, and having the desire to modify/customize the response, here are a couple of pics to help. Best thing to do is to defeat the boost circuit altogether, then tweak the HPF as desired, and as is common with other plate amps.

This pic points to the two resistors that need to be changed to tweak the HPF. They are located close enough to the edge of the pcd (near the led) that it shouldn't be too difficult.



This next pic is the back of the preamp pcb, and shows the two jumpers needed to defeat the bass boost circuit.



Here is the frequency response of my 200-6, after defeating the bass boost circuit, and modifying the HPF to an Fc of 13Hz, Q = 0.6.



We haven't had any user feedback about the non-boost models, but my suspicion is that they share the 30Hz HPF, but their boost circuit is configured for no boost. I will try to confirm this when my backordered 300W model arrives.
ZUes101 is offline  
post #103 of 120 Old 03-02-2013, 01:30 PM
Member
 
superspeeder's Avatar
 
Join Date: Aug 2009
Location: Ottawa, Canada
Posts: 31
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Subscribed!

I just bought an SD500 second hand and tested my new LMS-R 12 free air with a tone generator app... I couldn't figure out why excursion fell off rapidly below ~30hz! I tried the same with my Bash300 and excursion looked normal to below 20Hz. Now I know why!

garciab, what resistor values did you use to set your fc to 13Hz? This is exactly what I would lke to do as my build will be good down to the mid-teens. Thanks!

Also, does anyone see any reliability issues with modding the HPF? I can't imagine WHY a company would put a 30Hz HPF on a subwoofer plate amp, but durability might be a reason for it. Thoughts?
superspeeder is offline  
post #104 of 120 Old 03-03-2013, 06:17 AM - Thread Starter
AVS Special Member
 
garciab's Avatar
 
Join Date: Aug 2001
Location: Princeton, TX - USA
Posts: 1,033
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 28
R8 = 43k, R26 = 84k, values in this area should give you Fc = 12Hz ,Q of 0.7.

You do bring up a good point about affected reliability. If you read the hype of PE's site, you'll notice how Yung touts the amps ability to run full power for hours without shutdown problems. But we know their heat dissipation will be affected if we run then sub 20Hz. And heat is not a friend of electronics. Still, soundtracks are very dynamic, so as along as we aren't running sinewaves through them continuously, I think we'll be ok. But taking the risk is an individual determination.

bg
garciab is offline  
post #105 of 120 Old 03-03-2013, 07:52 AM
Member
 
superspeeder's Avatar
 
Join Date: Aug 2009
Location: Ottawa, Canada
Posts: 31
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by garciab View Post

But taking the risk is an individual determination.

I'm more worried about screwing the amp up by modifying the filters than overheating it - I live in a townhouse so high SPL listening is not often. Also, this sub is used 99% for HT, the nature of which is pretty infrequent LFE.

Thanks a bunch for working this out! This is extremely helpful. One of the hardest things to find out about an amp is the value of any subsonic filtering involved. Now I can set it myself!
superspeeder is offline  
post #106 of 120 Old 05-23-2013, 06:11 AM
Newbie
 
audio-enthusias's Avatar
 
Join Date: May 2013
Location: Sydney Australia
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Hi Guys,

I have a problem with one of these amps, the SD500 un-boosted version (actually this is the second one I have the same problem with, and cannot return it, bought through ebay and seller does not want to communicate, etc.). The issue I have is the unit does not power on the actual amplifier part, through the DC DC converter (I have pulled the main PBC off and tested which component has failed). To provide an idea of what is happening, the unit shows the red power light, and when an LFE signal is passed to the unit, the power light activates, and turns green. From there on, there is no output to the sub, the internal relay does not activate, etc. I have checked all components and traced the issue to a small 8pin IC on the back of the PCB (side which faces the plate) location on the PCB U2. This seems to be a power management chip, which switches the actual amp part of the unit on /off. Unfortunately, the surface of the chip has been sand papered off (no chip identification marking left what so ever), and because of this, I am unable to see if I can find a replacement chip on the internet. I believe this has been done on purpose, although this is just speculation. There is also another chip on the same side, location U1 which has the surface of the chip also erased.

Now to my request... If anyone has pulled one of these apart, or is willing to help, I need the part of this chip (location U2). If the same is present on your model as mine (the chip surface has been erased), then I require the output of this chip, on each leg. This way, I might be able to locate something on alldatasheet.com.

I would like to thank anyone willing to assist me in advance.

Image of the location and chip...

audio-enthusias is offline  
post #107 of 120 Old 05-23-2013, 06:18 AM - Thread Starter
AVS Special Member
 
garciab's Avatar
 
Join Date: Aug 2001
Location: Princeton, TX - USA
Posts: 1,033
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 28
I'll check my 500W CSS amp and see if I can help with the chip numbers. Also, you might try finding the guy (somewhere on this forum) that repairs the version of this amp that was sold through Elemental Audio designs. Maybe someone here knows his name? Edit: saw on another thread that user here named 'Daveds50' can repair these amps. See if you can contact him. 2nd Edit: I didn't find any posts by him on this forum, but I googled his name and found that he's a small electronics repair guy. His facebook page shows pics of the elemental designs amps like these, so he may be able to help you. Please let us know how it goes and what you learn.
audio-enthusias likes this.

bg
garciab is offline  
post #108 of 120 Old 05-23-2013, 04:03 PM
Newbie
 
audio-enthusias's Avatar
 
Join Date: May 2013
Location: Sydney Australia
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Hi garciab,

Thank you for the details you have provided me with. I have already contacted 'Daveds50' through Facebook, and have linked this topic and post number to see if he will be able to assist me with this issue. I will update with what advise I receive, and if I was successful in repairing this amplifier.

Once again, thanks for your help mate!!!
audio-enthusias is offline  
post #109 of 120 Old 05-23-2013, 06:14 PM - Thread Starter
AVS Special Member
 
garciab's Avatar
 
Join Date: Aug 2001
Location: Princeton, TX - USA
Posts: 1,033
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 28
Well, I hope he can help you. My amp has the markings on those chips sanded off as well. Good luck!

bg
garciab is offline  
post #110 of 120 Old 11-22-2013, 09:21 PM
Member
 
SULLY12's Avatar
 
Join Date: Sep 2012
Posts: 193
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
If I was to use the sd300 would I be able to gain back some of that dip by using my ed eq.2 ? My boxes are going to be tuned to about 17hz so how would these amps do in that box?
SULLY12 is offline  
post #111 of 120 Old 11-25-2013, 07:51 AM - Thread Starter
AVS Special Member
 
garciab's Avatar
 
Join Date: Aug 2001
Location: Princeton, TX - USA
Posts: 1,033
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 28
In my opinion, it's best to have the least amount of signal processing as possible. I prefer to remove any signal processing, rather than add more to compensate for some that is unwanted. These circuits have their limitations, and you don't want to add distortion trying to overcome a bad response that can be eliminated or minimized.

bg
garciab is offline  
post #112 of 120 Old 11-25-2013, 08:30 AM
Member
 
SULLY12's Avatar
 
Join Date: Sep 2012
Posts: 193
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
Thanks for the input.
SULLY12 is offline  
post #113 of 120 Old 12-10-2013, 06:57 AM
Member
 
Steve Kuester's Avatar
 
Join Date: Jan 2005
Location: Gumption County, MN
Posts: 86
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 13
I just received my Yung 300-6 yesterday. I will be using it with a passive SVS 20-39. My 20-39 has a custom port and is now tuned to 17Hz. This will be used in a 2.1 system for 99% music, and I will have a BFD (parametric EQ) inline before the Yung.

My question is this...

I was initially going to set up without modifying the Yung just to see what kind of response I get in my room and then modify if needed. But... Is there any reason to not just make these mods right away? Reason other than the warranty voiding, I mean. I like the idea of a flat amp and a lower roll-off on the HPF, and I only have so much time to play around with this due to life, kids, work, etc.

The mods I am referring to are shorting C13 & C14, and changing R8 and R23 to 34K and 68.1K for an Fc of 15Hz.

If you can't tell I'm leaning towards doing the mods first instead of trying as is... just wondering if there is reason to NOT do the mods first that I am just not seeing.

thanks,
steve

I turn the sharpness on my TV all the way up, because that's how I like my picture... real sharp.
Steve Kuester is online now  
post #114 of 120 Old 12-10-2013, 07:09 AM - Thread Starter
AVS Special Member
 
garciab's Avatar
 
Join Date: Aug 2001
Location: Princeton, TX - USA
Posts: 1,033
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 28
That's quite a pickle...on one hand you don't want to touch the amp until you know it works. But you'd like to take advantage of the limited time you do have to mod at once. Warranty and possible defective amp are the only reasons to not mod right away. It would be nice to make sure it works first, in case if the worst were to happen, you would at least know that you may have made a mistake during your mod.

I recently did a mod for someone on this board. It was a brand new amp, and I made sure it worked before I touched it. Ran some FR sweeps before and after modding to make sure amp was functional in both states.

bg
garciab is offline  
post #115 of 120 Old 12-10-2013, 09:51 AM
Member
 
Steve Kuester's Avatar
 
Join Date: Jan 2005
Location: Gumption County, MN
Posts: 86
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 13
Yeah, I know you're right. I really should make sure it works first.

Thanks for the quick reply and for talking some sense into me.

I turn the sharpness on my TV all the way up, because that's how I like my picture... real sharp.
Steve Kuester is online now  
post #116 of 120 Old 12-10-2013, 11:56 AM
Advanced Member
 
Face2's Avatar
 
Join Date: Mar 2007
Location: Long Island, NY
Posts: 648
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Liked: 41
Just curious, why would you select an amp with bass boost for a ported sub?

Mike
Face2 is online now  
post #117 of 120 Old 12-10-2013, 12:27 PM
Member
 
Steve Kuester's Avatar
 
Join Date: Jan 2005
Location: Gumption County, MN
Posts: 86
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 13
I was going to get the non-boost version, but it was out of stock at both parts-express and amazon.

I was aware of this thread, I liked the price ($99) and I have no problems with modifying it... so I went with the boost version.

And, parts-express was also out of the boost version and there was only 1 left on amazon, so I jumped on it.

I turn the sharpness on my TV all the way up, because that's how I like my picture... real sharp.
Steve Kuester is online now  
post #118 of 120 Old 02-06-2014, 12:42 PM
Member
 
Steve Kuester's Avatar
 
Join Date: Jan 2005
Location: Gumption County, MN
Posts: 86
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 13
Anyone ever try to defeat the Auto-On feature on this amp and turn it into an "Always-On" switch? Sometimes I get annoyed that I'm missing the bass on the first half-second of a song. Sometimes if I listen at a quieter volume it does not turn on at all. I've got my sub crossed over at 100Hz and I do notice if it is not on - even at lower volumes.

I turn the sharpness on my TV all the way up, because that's how I like my picture... real sharp.
Steve Kuester is online now  
post #119 of 120 Old 03-31-2014, 10:18 AM
Advanced Member
 
nograveconcern's Avatar
 
Join Date: Aug 2012
Posts: 565
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 52
Quote:
Originally Posted by Face2 View Post

Just curious, why would you select an amp with bass boost for a ported sub?

A little late on the response, but because you have a large room with a ported sub in an enclosure that is too small to achieve a flat response in room. Or you just like boost at 30hz.
nograveconcern is offline  
post #120 of 120 Old 04-02-2014, 09:45 PM
Member
 
Bombelman's Avatar
 
Join Date: Nov 2013
Location: Paramaribo
Posts: 180
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 33
great write-up !
Bombelman is offline  
Reply DIY Speakers and Subs

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off