First discrete amp, Need help with NTE 390, 391, 375, 398, and BD140, 139 project

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pacificblue said:
I just rediscovered this link. It includes interesting insights (whoa, I'm alliterating!) about some of the many topics in this thread. And it is easy and fun to read.

The 3 dB comparison to show the difference between a 100 W and a 200 W amp (or any doubling of power) is a must hear.


Oh, thank you!!

Ready for a headache?

I'm sorry for the delay. I've been working on a way to change that 3db figure upwards by 142% (aka 4.26db). Likewise, either the original or especially the resulting amount of power is practically useless inside a house, I've also be working on a way to swing a decrease by 142% (aka both up and down by an additional 1.26db). As you know, figures are approximate and my calculator is feral. ;)
This method, although popular with speakers isn't technically seemly within an amplifier until its application is clearly defined and the usage limited to that. That limitation would be "only for one room" or "only at short distance."

After much research, and that little problem of having no use for a 200W amplifier, I've decided to further define the purpose of this particular amplifier to one room, indoors. And now the unseemly part. . . Hindering the amplifier's control not only makes speakers work in smaller boxes but also makes larger soundfields fit into smaller rooms.

There is the purpose and the potential use of the very powerful amplifier at point blank range. . . It takes a considerable amount of power to make a large soundfield, and this is true whether it is efficient shouty long-distance high voltage output or whether its a rather inefficient large size presentation at lower voltage. The necessary power for a concert size presentation remains the same. I don't know why, but herein, somewhere herein, is the potential use for a 200w amplifier at nearly point blank range.

Defining the application as different than general purpose, I expect it to perform the same job as a home theater or nightclub rig, but do it with only two speakers, making the same large size presentation actually fit into an ordinary living room. Please view the resulting project within the bonds of that specific application.

This can be done. It does involve lousing up the motor control ability of the amplifier in order to decrease the distance reached by the speakers, with the hopes of increasing the width or "openness" of the soundfield. For reference of some of these techniques, see Joe Rasmussen's Elsinore speaker project. Also see the practices of "padding" midranges and tweeters.

One possible amplifier that does this is a bridged amplifier with output caps on the + outputs and also a buffer at the input. This operates on single rails power and doesn't require an NFB cap. There are tradeoffs. However, these tradeoffs favor the ear when the amplifier is used within a small venue, such as a home.

I'd sure like some additional documentation on these techniques. An amplifier that is an "application specific" specialty item for creating big size presentations in small rooms. . . is of great interest. There seems to be endless ways to do this, but I'd like avoid overkill, no matter how tempting that might be. ;) I'm guessing that several small accommodations makes higher fidelity than one large effect.

Establishing the boundaries is going to be important. There's no doubt that an extremely powerful general purpose amplifier is an application mismatch for a very small venue. There's one boundary. Also, we'd not want to cut the distance too short because that would be only noise. So, there's the other boundary. In-between these two points is. . . something else. Identifying what is it and how much is "right," is terribly difficult.

Like Joe's speakers wired in series, a similar effect can be done within an amplifier via either a capacitor in a fortunate application or a capacitor paralleled with a resistor or a capacitor paralleled with a voltage divider (center is output). You get the typical boost from a capacitor. There are also some buffers (like Nick Whetstone's plans for a discrete buffer) that not only run the signal through the buffer but also run the signal through a resistor. Like Joe's speakers, the best form of "padding" is when the energy isn't wasted, but rather follows two or more paths. The resulting device also serves as an un-compresser.

Negative feedback isn't a problem, but rather the some of the errors in its typical applications are generally disturbing to the listener--which is not acceptable at all. Most people accept the noise, but I call it tripe. Its not without benefits. Of course we're familiar with the boost in dynamics that comes from the NFB cap. Unfortunately, if that's done at the NFB, you also get a proportional increase in audible noise that certainly doesn't favor the ear. Let's choose a different option, that even if the noise is greater, doesn't cause a well-known hindrance to the nearby receiving device. This is also why I get really excited when measuring equipment happens to show something that matters.
My best guess is output caps on a bridged amp because of the clean negative signal that doesn't go through a cap, can use anything for a reference, as long as there is a reference. This is much different than using an NFB cap. I think that I'm attempting a power amplifier with "multipath" audio like Joe's speakers or Nick's buffer. I'm trying for "more numerous amplifier pathways" rather than "many speakers," and still get the sound of "many speakers," while actually only using two speakers. Is this sort of technique more noise or less? I think that the answer depends on the application (that we now have). ;)

Well, that's what I've been working on lately.
Its intense! Help!!! :D
 
Q: Which source is better? A: All of them. ;)

anatech said:
Hi homemodder,

Digital Media Rights.

Microsoft wants to get into controlling our media in a big way. Nothing good will come of this and they won't let quality stand in the way of complete control!

They already have our young'ons trained to enjoy MP3s. Soon, good quality music will be outlawed.

-Chris

I think that the MP3's work somewhat better than the 8-track. :D

It seems that some signal types like MP3, WMA and the disturbing waveform output of Class D, are all judged by total system symmetry, as in eventually what the ear does with them.

And, there we can get one potential answer from audiology. One source all the time can be as exhausting as a nonstop car horn. So, it seems that the way to manage MP3 is to have several different codecs or in some way have a rather huge variety. It also seems important to listen to the radio and LP's and CD's and attend concerts. This is so similar to decreasing the noise by increasing the differences to the reference point.
This is why I think that the answer to "Which Source Is Better?" questions is. . . all of them.
 
anatech said:
Hi homemodder,

Digital Media Rights.

Microsoft wants to get into controlling our media in a big way. Nothing good will come of this and they won't let quality stand in the way of complete control!

They already have our young'ons trained to enjoy MP3s. Soon, good quality music will be outlawed.

-Chris


It's not really Microsoft. It's the RIAA and other record companies. MS are simply giving them what they want. So were Apple too, for long enough.

At least Apple had the sense to push AAC rather than MP3 or some custom thing. High bitrate AAC (or a better codec, Musepack is my favorite) are great sound quality. Lossy != Bad when it's the right codec in use. I have self encoded Musepack's that I can't distinguish from the original lossless format.
 
homemodder said:
Since this thread has already gone far off topic, here is another question aimed at the computer bofs here, hope someone here has answers as Im tired googling and its audio related.

I have set up a new computer for myself, my old new one relegated to the girlfriend. Now, I hacked windows XP into kingdom come :D and you couldnt tell the difference between it and windows 7, the problem is mediaplayer 11 and 12. Microsoft has continuously put up new codecs for audio but I want to use the old mediaplayer 10 codec, the reason being the the new codecs are junk and mediaplayer 10 has the only good sounding codec and remains the best sounding mediaplayer. The new codecs and mediaplayers seem to do whats happening in the recording industry, loudness compression, I wish the industry would stop with this :bs: :cuss:

Where do I locate the codecs files and is it possible to swap to mediaplayer10 codecs without having to revert to the complete mediaplayer10 program ???

Before someone asks, no I dont want to use other programs, besides mediaplayer10 sounds superior to them. I will try third party codecs if they are good and are of audiophile quality.

Hi Homemodder!

Do you have the same sound card? Does it test the same way with RMAA on both computers? Did you have the wav output on one card set to 60% or less, while the new card is up at 100%? Are they using different native rates? Have you changed the location of the transducers or their recipient?

If its not hardware then, I have almost no idea. . .
except for something you can do about it.

Here's a possible kludge answer that should work. Use no codec:
Using the old computer and the well-performing software, get TuneBite or any other "digital loopback" (What U Hear) recorder and export the output in .WAV format. If your sound card only records at fixed native rate, then attempt to output with some form of lossless codec at the native rate. This should facilitate recording your preferred sound into a lossless file that is now software independent. If you wish to later re-compress the file, it will take a minimum of 200% file size increase in order to avoid dramatic loss of fidelity.

Here's a hideous answer that I don't like, but it works for sure:
If you've acquired non-working technology, then "taking out the trash" may be overdue. I had this problem and tried everything on the new computer (very spendy), but eventually determined that the new power supply and the new motherboard and the new software were all causes of results that didn't match my preferences. As for the new computer, hacking the operating system into unexpected operation may be causing. . . unexpected operation. ;) The problem could possibly be with basic efficiency, such as having the computer doing a great deal of unnecessary may be hindering it from performing more important tasks.

Off topic?:
Personally, I'd like to view this thread as both how to do and what to do with the amplifier, in a system symmetry approach. ;) I can't help but think that the audio chain wouldn't work unless it is complete, all the way from source to ear. Also on efficiency, I think that a complete audio chain must justify using the power cord.

Towards the purpose of better efficiency in the only real purpose of audio playback equipment, benefiting an ear, then if you desire less loudness compression (un-compressor), this indicates something that you should probably do. Its especially applicable to playback of MP3, WMA and similar audio sources.
However, it is the contrasts of variety that really increases the reception abilities of the ear itself. So, I like to keep my favorite tracks in extra high quality even if that happens to require more hard drive space. Yet, I couldn't regret having a wide variety of quality levels as long as they are all useful. While one big coloration will dull the ear's reception, many small coloration don't have that problem.

Other thoughts:
Amazon.com sells an enormous catalog of 256 rate MP3's, so it is unnecessary to purchase audio "stuck" in WMA format.

Audio compression (loudness compression / voltage swing decrease) is vitally important for lossy codecs because only loud information is saved at highest quality. That's both audio compression and file compression. Naturally you'd want both matching forms of un-compression to work as a cancellation, if hi-fi playback is desired. This concept isn't remarkably different than the RIIA technology in turntables or Dolby technology in tape decks. Its simply that the new format's complexity makes cancellations upon the noise more difficult to have a precise match.

Its also good to attempt playback with exactly the same codec that was used for recording. That's not always true, but I think it is a generally useful practice. Since software will probably be changed (often automatically, with no advance notice whatsoever), I think its good to export good results to a lossless file format in order to protect the investment away from deprecation of its matching playback codec.
 
jaycee said:
It's not really Microsoft. It's the RIAA and other record companies. MS are simply giving them what they want. So were Apple too, for long enough.

At least Apple had the sense to push AAC rather than MP3 or some custom thing. High bitrate AAC (or a better codec, Musepack is my favorite) are great sound quality. Lossy != Bad when it's the right codec in use. I have self encoded Musepack's that I can't distinguish from the original lossless format.

What settings do you recommend for Musepack?
 
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Joined 2004
Paid Member
Hi jaycee,
It's not really Microsoft. It's the RIAA and other record companies. MS are simply giving them what they want. So were Apple too, for long enough.
I disagree with you regarding the Microsoft thing They are after the entertainment market now as well. There were some articles on that. As for teh rest of them, completely agree. The upshot for we consumers is that everyone is still trying to rip more money from us.

In my book, the RIAA is truly despicable, and greedy.

-Chris
 
anatech said:
. . . In my book, the RIAA is truly despicable, and greedy.

-Chris

Hi Chris!

I think its remarkable how much less work they are doing for music artists than in the years and decades before.

Its also amazing that they assume that the public won't know about anything that can be seen and heard, can therefore be recorded. It is simply impossible for DRM to work unless the programme material can neither be seen nor heard. Its really just a bit too late to remove every sort of high quality recording device from the market. The assumption that DRM could work is illogical.

That is yet another thing to add to the already huge list of what they're not accomplishing.

So, what is really going on?

Are the people in question really just furnishing their own self-justifying job descriptions, at the expense of everyone else? The word for that is theft, isn't it?

Honestly, I just don't know what they're up to when their cost is so far disproportionate to their benefit. What are they doing anyway?
 
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Joined 2004
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Hi Daniel,
In my own personal opinion, they are only lining their own pockets. If I buy the rights to some music, if the media fails, I still have the right to listen to the material. One of the excuses they used for expensive CD's costing more than the LPs they replace was the idea of granting a personal use license.

I don't steal music, I don't download anything as the sound quality isn't worth it. This entire downloading thing that you do pay for per item is a suckers bet. In the old days, if the sound quality wasn't good, you could exchange or return the product. Not anymore. Now you get garbage after paying for it, with no excuses! Then the music is only good for "X" number of copies. Nope, not good enough for me.

If I have a CD that gets damaged, I'm going to copy myself another from someone else. I don't really care if they feel it's not legal, but I am not copying anything I haven't bought. I also make copies to use in the car. I can only listen to one at a time.

I'm sure if you asked RIAA if they were doing anything at all for the original artist, they would tell you emphatically that they were. Bull. They are lining their pockets and imposing unfair taxes. BTW, most of my recordable CDs are used for data, my own files. I only have a couple recordable CD's with music on them. I have never recorded a movie onto DVD, again, that's all data. I resent any additional costs because I "might possibly" record some artists work on it. That is robbery as far as I'm concerned.

Then we have Sony installing root kits to protect their interests. That should have been a "hacking" or virus charge with a large settlement. They got off so lightly that you just know they have support from higher up.

-Chris
 
anatech said:
Hi Daniel,
. . .
Then we have Sony installing root kits to protect their interests. That should have been a "hacking" or virus charge with a large settlement. They got off so lightly that you just know they have support from higher up.

-Chris

It happens the other way around too, and its so very expensive. Unfortunately, its cheaper to go with than against.

A rather painful (to the wallet) personal event lately. . .

A small town computer "builder" who serves 4 counties has been doing "bargain" computers for years. All of them have been coming with Windows XP Professional Corporate Edition and Microsoft Office Professional. Some of these have been selling as low as $175. Do the math. This guy was my competitor back when I (previously) was in the computer business. And, it was near impossible to compete with his repainted dumpster dive deals.

While I have never sold a computer with improperly licensed software, I did have (previously) some home computers that were in need of a touch up, or at least some more-solid proof. It became urgent. The software piracy raids have reached a city just 100 miles south of my house and it is confirmed that they are progressing North. The really questionable computer "builder" is located only 12 miles away, and "in the path of destruction."

I'm directly in-between the two locations; so, I've just purchased $975 worth of licensing from Microsoft. Its 6x xp pro and 6x office home.
And, I will be going through every last bit of their "requested and required" software registration rigmarole. Alternative options are limited features, using something I've no idea how to work, cyclic reformatting, relearning (in order to avoid all that reformatting); and honestly, it turns out that just paying out is cheaper and less annoying (at this time).

Did I want to send a big sum to Microsoft? No. It is especially difficult at this time. But, as for self preservation, it seemed necessary as I'm directly in the line of fire. Its just nasty to have further supported those people. Ack! This flavor is terrible, reminiscent of falling headfirst in the catbox. ;)

I shall hope that it will be the last time these sort of people get any money from me. Before taking this step I tried and tried to get Linux to work for me. It was close, but it fell short. The good news is that Linux is getting MUCH closer than before. For instance it didn't take three days and four pages of complex instructions in order to network it, like what happened on last year's interview. Now, I still couldn't do everything with it, and a new bug had been added to the menu system which wasn't at all reliable, plus the speed has decreased by half. With more progress than faults, I have to report that one of these days soon, you will be able to stick in a Linux disc and receive what you want.

But it was not soon enough.
With, soon to be, quite literally, guns pointed in this direction, there was only one option that was both instantaneously fully functional (for me) and absolutely certain. Short on options and short on time. . .

The fees that I have just paid to Microsoft for licensing have now gone directly towards increasing the problem you're talking about. My apologies.
 
Daniel

I had to reply to this one .
No way would I fork out 900 , Id rather spend it on myself...learning .

Linux...my work runs on it , was Unix SunOS , now RedHat Linux on PC's . It works , no querks . ( unlike this home PC )

take a class or two to learn all about Linux . Might pay off !

Wayne
 
Administrator
Joined 2004
Paid Member
Hi Daniel,
I have to agree with Wayne, except that I am forced to run Microsloppy for some apps.

One big reason I hate these people. When you buy a license, you get support in the bargain. Every single time I have had a problem that they could not blame on other vendor software (that's also every time), the only advice is to reload the OS.

That is not support, and frankly, if they are unable to provide support they have no right to demand money for it. When I was running O/S 2, I only had a couple problems. Each time, IBM got the info and provided a fix or workaround within a week. Then they even called back a week later to confirm everything was still working fine. My OS/2 Advanced server didn't suffer memory leaks. In fact, I was using JFS (Journaled File System, of Unix fame), mirrored drives. It booted faster in case of shut down, like long power fails at night. You could even turn it off while it was accessing the disc and it would come up each time with no problems. Sure, you might lose some data (thank god I was using Filepro, network aware, but never the OS. My NT4 box needed to be reloaded about 30% of the time. My Linux test machine needed a reload 100% of the time when that happened. The best feature about OS/2? When you hit Ctrl-Alt-Del, the system performed and orderly shutdown. I crashed the OS/2 box several times while trying to log onto Windows. :mad: Idiots at usloppy! I finally bought a KVM switch.

If I can get Linux running as a server, that's step 1. Once I can port my workstations over to Linux, it will be so long Windows! Too bad XP has been the most stable Windows product yet. Did you know that Microsoft even botched one release of DOS???! Yes, they did, and I got mine refunded. It looped a sub-directory back to the root. Bye-bye disc access, all info gone. Backups are needed to survive any Microsoft installation.

At least you are legal Daniel, so am I. I happily bought legal copies of OS/2, 'cause they worked and were supported. The last release I had running was OS/2 R4, and it was nice!
 
udderslate said:
Daniel

I had to reply to this one .
No way would I fork out 900 , Id rather spend it on myself...learning .

Linux...my work runs on it , was Unix SunOS , now RedHat Linux on PC's . It works , no querks . ( unlike this home PC )

take a class or two to learn all about Linux . Might pay off !

Wayne

Thanks for your reply and quick analysis too!

I meant no disrespect. Its just that I needed something immediately fully functional. Unfortunately, that happens to involve the end-user, plus a very short timeframe (as is implied by "immediate"). I was literally soon to be in the line of fire, and I got that problem fixed in less than one hour's time.

I'm aware that Novell and Oracle both endorse Linux, and so it must be an excellent operating system. Together, its the safest place for data, and there is no doubt of that. I wouldn't want to disrespect these people, nor their recommendation of Linux.

I merely postponed the move to Linux. I didn't and wouldn't rule it out.

What has been ruled out is Windows Vista and the "Vista Reloaded" product currently named Windows 7. Since these directly support questionable practices, I refuse them without exception.

I do like XP Pro and Linux in combination. That is trouble-free, but I do not run the automatically unexpected changes stuff that is proven to cripple reliability. Linux in a server role has freed me from that bother (automated "IP block on port scan" routing server). However, I am not willing to take classes to learn how to use my desktop computer when it already works perfectly well. In my opinion, one should not expect that option to be popular.

But, that is coming soon, isn't it?
 
anatech said:
Hi Daniel,
I have to agree with Wayne, except that I am forced to run Microsloppy for some apps.

One big reason I hate these people. When you buy a license, you get support in the bargain. Every single time I have had a problem that they could not blame on other vendor software (that's also every time), the only advice is to reload the OS.

That is not support, and frankly, if they are unable to provide support they have no right to demand money for it. When I was running O/S 2, I only had a couple problems. Each time, IBM got the info and provided a fix or workaround within a week. Then they even called back a week later to confirm everything was still working fine. My OS/2 Advanced server didn't suffer memory leaks. In fact, I was using JFS (Journaled File System, of Unix fame), mirrored drives. It booted faster in case of shut down, like long power fails at night. You could even turn it off while it was accessing the disc and it would come up each time with no problems. Sure, you might lose some data (thank god I was using Filepro, network aware, but never the OS. My NT4 box needed to be reloaded about 30% of the time. My Linux test machine needed a reload 100% of the time when that happened. The best feature about OS/2? When you hit Ctrl-Alt-Del, the system performed and orderly shutdown. I crashed the OS/2 box several times while trying to log onto Windows. :mad: Idiots at usloppy! I finally bought a KVM switch.

If I can get Linux running as a server, that's step 1. Once I can port my workstations over to Linux, it will be so long Windows! Too bad XP has been the most stable Windows product yet. Did you know that Microsoft even botched one release of DOS???! Yes, they did, and I got mine refunded. It looped a sub-directory back to the root. Bye-bye disc access, all info gone. Backups are needed to survive any Microsoft installation.

At least you are legal Daniel, so am I. I happily bought legal copies of OS/2, 'cause they worked and were supported. The last release I had running was OS/2 R4, and it was nice!

Hi Chris!

My Intel Atom + APFC + XP Pro branch office server is running quite a lot, flat out, using 7% of the $8 cpu, and has not ever required a restart or reload. It boots (totally) in 9 seconds. That was about a month ago, when I decided it should have a bit better fan (120mm intake). For servers, I require cold (room temp) air is emitted from the power supply and the easy way to really do that is to push the room temp air into the box. ;) So, I guess that it has required just that one restart (because I took it apart to cut a 120mm hole in it). I had no idea that you could get that particular hardware piping hot. ;) Its cool now. It also runs Zone 8 and FULL DEP, because there is only the one server. Oddly enough, the first class support hardware on the weak little board, has made much better uptime than the AMD system. There seems to be some sort of automatic throttling involved, and the system will not crash. I did one like this before, many years ago. I had an NT proxy server that wouldn't stay up. For a repair, an old intel board worked just like viagra. That was slower at the console, but far out faster as a server. NT then, and XP now, stay up with that weird approach. The console might (might) get the hourglass, but the clients do not. I wonder why?

P.S.
Efficient little file server relates to this thread's topic as a possible home server, and also relates because sound cards make stable frequency response (expected results) on Intel 945. One would apply this with a fast hard drive, like the Western Digital with the 16mb onboard cache (runs cool = energy efficient, and its fast), and a PC Power & Cooling APFC supply with certified efficiency. Getting cool air into the box also applies to amplifiers. This is just for reference on how this post may apply to this thread.
 
Whats unbeatable about MS , is that it has a large acceptance , most everything is plug.play , and bonus lots of freeware for us .
Darn worms,viruses and all that though ...
a curse of being a popular system .


I gotta be honest though , I haven't switched ..yet . I want to try it on
a spare machine first ..wifey uses this one , and hates change .
At least I got her using Firefox/Thunderbird OpenOffice .
Should I switch to Linux , she can still use those !

Enough about this though , to me an OS is a productivity tool ,
and for surfing DIY Audio .

Id rather talk about what you started in this thread...
you gonna build something or what ?
After months of frugalamp reading ,I just ordered heatsinks .
Now to order more and build things .

Cheers
 
the first class support hardware on the weak little board, has made much better uptime than the AMD system.

I guess we are on the same page, I just became fully "amd free".
AMD is good (lasted 3 years) but MS and intel seem to be
in better sync software/driver wise. The 945 is a wonderful chipset , if it is accompanied by solid caps and a good PS you
should get 6 years + out of it ,24/7 use.

I don't know why some have all these XP problems, but only
1 bad 3rd party app or a bad driver can give it a bad name.
Using onboard video will also cause unexpected issues.

XP SP3 and ubuntu 10 both give me no problems (XP for
the server , ubuntu for 2 workstations).

After months of frugalamp reading ,I just ordered heatsinks .

From the opposite end of the hobby (DIY) , I just finalized
the frugal 2T (triple) absolutely the best prototype and
simulation of them all.. not too much more complicated than
the 1 , but easier than the 3. March 1st I will have parts
and PCB's.. a sneak peek (attached)..
OS
 

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OS
I already peeked ....
If you don't already know that from your logs .

You have a broad range of other stuff on your site .
Do you collect this , or have you read/learned all this ?
Keeping me up way to late .

Interesting side note.... can't buy Muriatic from HomeDepot. ( Vt)
Another store in town , keeps it outside in a concrete shed !
I think the local Ace has it .


be back tomorrow .
W.
 
Disabled Account
Joined 2006
That piracy taskteam should come to my place, I will offer them tea and cookies for it will take them a while to figure out just exactly what OS I have. :D :D :D

Although I have a licenced copy of microsoft XP which came with the computer when purchased they wont like all the third party kernells, configuration services, executable files and much more, they are not the only ones that know how to write software. The microsoft OS is no more a big secret although I agree that it is much more funtional and easier to use than Linux. Never had any stability problems.

After that theyd be most welcome to try sue me, they still have a couple of unresolved lawsuits against them here in europe and so far theyve lost all previous cases and paid over 600 million Euros in fines, theres no US goverment here to protect them from rightfull anti competition and anti trust lawsuits. Their unfair business practices dont go unpunished here. The fines slapped on them here have reached a record 2 billion dollars, that will teach them. :D :D :D :D :D :cool: :eek:
 
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