Amp too good for DIYaudio.

[gwing]

??

What don't you understand?

 

[Sir Sanders Zingmore]

What don't you understand?

your post

 

[JeremyFife]

This thread is getting odd.

If its about amplifier design (DIY) then I suggest starting again with a new thread.

If its a disguised rant against another forum, just stop.

Also, please don't use another's handle, it's poor etiquette.

Either way, I'd suggest that this thread is done.

 

[gwing]

Why would you use someone else’s alias even with their permission?
IMO it’s against basic etiquette to others as it causes confusion particularly if you’d already been accused of being his sock puppet

Quite. And also, even if these are two separate people and not a sock puppet as suggested it is completely wrong to use someone else's ID on a forum on which you have been banned, that likely gets you a permanent and irreversible ban on most forums.

 

[Drengur]

This thread is like a plot in a movie I would watch. If this was a movie the old electronics designer living in a village in Holland somewhere was probably replaced by an evil AI he accidentally made self-conscious by using seemingly ordinary parts he salvaged from either a military outlet or a Romanian woman in a trailer. Either way, he is being held hostage by this rogue AI who assumes his identity on audio-forums in order to dupe people into building more self-conscious AI because of their greed for more SINAD. The second movie will be a money grab and I don't recommend it.

 

[Wesseling Audio Lab]

I'm waiting for the scene where the gerber sisters arrive. The suspense is palpable

 

[jamescarter1982]

Welcome to the forum, don't know enough amplifiers to offer a comment but the numbers sure seem impressive.

DIYaudio.com is straight up the worst place I've ever been to regarding audio equipment (ok maybe gearspace is worse, hard to tell). I'm always shocked at how incredibly stupid people are there and how all the stupid people corral behind each other if you ever try to provide any sort of evidence to back up your claims. I don't use the word stupid lightly either, the majority of users there are really anti-science and moderation barely exists. I guess if you're banned you might miss out on the fact that the site is 99% noise and 1% good contet that is buried in 300 page threads. You're going to miss out on planet10 telling you all speakers that aren't full ranges are bad.

people can be so rude on there as well .like if you ask a question even if your just trying to have a chat sometimes they can get all preachy and patronising

 

[Koifarm]

Update Trex 4b .

As promised the files for the big version.

Schematic

Attached also gerber files for ordering the PCB.

And in the attachments LTspice simulation.

This PCB you can also use for previous versions:

- When use only one 10N20 and 10P20 you get 65Watt amp using +/- 36V power supply.( Trex 2C).(also lower cost)
- When use two 10N20 and 10P20 or one 20N20 and 20P20 you get 150Watt using +/- 48V power supply.
- When using two 20N20 and 20P20 you get 350Watt amp using +/- 65V power supply.( Trex 4B).

I am using as power supply one Hypex SMPS 1200A400 for one Trex 4b board.

Blockschematic of one channel.

Ronny

 

[Koifarm]

C12 had no ground connection. This corrected. And C16/C17 were wrongly coded. All corrected in gerber below.

 

[ta240]

There is this diversity on ASR too. Almost everyone on here acknowledges the fact that taste and subjective enjoyment is essential when it comes to music.

The main difference is the awareness of that, and the relation to how actual gear scientifically, measurably, provenly behaves. Nobody defends objective nonsense that tries to present subjectivity as fact, but opposes it. The other way around, if you got a specific taste and sound character goal, we try finding scientific and efficient methods to achieve that. Stupid example: you like a bass boost and slight treble rolloff, aka "warm" sound? Magical cables aren't the way, but EQ is. Same with speaker choice and design. You got some hilarious idea and actually like a "bad" design? Go ahead! Just don't present your taste as objective truth, and all is well.

Science and physical truth is a great method to achieve maximum musical enjoyment. It works, for all tastes.

After several years reading this forum I have only seen the attitude in the first paragraph form a couple members. And they usually get shouted down by the rest of the posts. The overwhelming responses to anyone that posts that they like anything other than perfect reproduction of the sound, is that it is wrong to do anything that alters it from the original. Amplifiers that aren't deemed perfect are mocked as effects generators. The overwhelming response tends to be that the listener should learn to enjoy the music the way it was recorded instead of using any form of reproduction that makes it more pleasant for them.

The second paragraph is more into the result here but not just 'magical cables'. If an amp produces the sound they prefer they are told they should still get a perfect amp and then alter the sound digitally to fit their needs. Because anything that isn't a 'wire with gain' is just wrong.

If the claims above were true we'd see threads where the response to someone enjoying a tube amp would be "They aren't for me, but I'm glad you enjoy it" and I don't think threads like that exist (beyond the 2 or 3 people that consistently have that attitude in those threads).

And we go from the first paragraph of 'personal taste is crucial with the enjoyment of music' to the final paragraph where it becomes 'science and physical truth are what everyone should pursue'. In one short post it went from accepting what others enjoy to basically dismissing it and telling them how to enjoy music.

 

[Jim Taylor]

And we go from the first paragraph of 'personal taste is crucial with the enjoyment of music' to the final paragraph where it becomes 'science and physical truth are what everyone should pursue'. In one short post it went from accepting what others enjoy to basically dismissing it and telling them how to enjoy music.

ASR is not about telling others "how to enjoy music". That is as wrong-headed as saying that we are telling others which type of music to enjoy ... and there are several threads here with hundreds (or thousands) of posts that prove that members here enjoy an astonishing variety of music.

ASR is not about music per se, and it's not about enjoyment per se. It's about the advancement of and appreciation of science in audio ENGINEERING. Somewhere back in the depths of this forum, Amir even discusses the name for the site, and admits that it might have been better to have named it Audio Engineering Review rather than Audio Science Review.

Many people cannot separate the message from the messenger. In audio, that means that they cannot separate the equipment from the enjoyment of the music. Many subjectivists are guilty of this false equivalency, and equate criticisms of the equipment with criticisms of the music, criticisms of the enjoyment thereof, and even criticisms of a more personal nature.

ASR is none of those things.

Just because you like driving doesn't mean that your ideas of tuning motors and suspensions are valid.
Just because you enjoy drinking wine doesn't mean that you're a vintner.
Just because you love to paint doesn't mean that you understand the chemistry of pigments, binders, solvents and resins.
Just because you love gourmet dining doesn't mean that you're a four star chef.
Yet behind every single one of those enjoyments lies a group of skilled, level-headed master technicians whose work (and whose attitudes) are the scientific foundations of what you enjoy.

So .... at ASR, we DO separate the message from the messenger. We DO separate the engineering from the enjoyment. And to make again a point that has been made thousands of times, we DO separate the objective from the subjective.

Many of us (I am one) came here to escape the muddle-headed confusion and, as I mentioned, the false equivalency of subjectivist websites. That doesn't mean we enjoy music less. It also doesn't mean that we aim our criticisms at whatever music you enjoy or how you enjoy it.

It simply means that we appreciate that engineering and enjoyment are two totally different areas of human endeavor. We engage in ... and appreciate ... both.

 

[Ropeburn]

And we go from the first paragraph of 'personal taste is crucial with the enjoyment of music' to the final paragraph where it becomes 'science and physical truth are what everyone should pursue'. In one short post it went from accepting what others enjoy to basically dismissing it and telling them how to enjoy music.

I don't think you understood my meaning.

What I'm saying is that taste and science go hand in hand. Work out how your tastes and preferences translate to provable, scientific data, and the science becomes a great tool to satisfy your taste - because you understood what it factually means! Then you can choose gear accordingly much better with that knowledge. And improve your audio setup and experience towards your preferences.

Nowhere did I write anything about dismissing others' taste or about telling them how to enjoy. On the contrary.

Science is a very helpful tool for enjoyment! That's the essence, and what ASR provides in abundance.

 

[Wesseling Audio Lab]

I ordered these boards. Eventually I'll get one built. My main issue with the design is output devices are not available from Newark, Mouser or Digikey

 

[Koifarm]

You can buy it here : https://www.exicon.info/purchase.php or here: https://www.audiophonics.fr/en/search?search_query=Exicon

 

[Hayk]

Permit me (another banned) to give you advice about PCB.
Pass the Dies Irae of Verdi and listen if distorting.
If it is the case, which is for Wolverine of DIYAUDIO, your PCB is radiating half wave rectified current from the supplies. The +V and -V are very far apart and the wires cannot be twisted.
MY remedy for the PCB, is to mask the supply and the output tracks to keep them naked and let the user solder upon them magnetic wires. It can be either capacitor leads or acoustic guitar brass wound strings. These strings can also be isolated by termoretractables to link the power supply.

 

[Koifarm]

And a newer version T-rex 5c with XLR and rca input and DC protection.
And even better thd (0.000045%).

For Q1 you can also use OPA1656 on adapter.
My subjective opinion is, I like this amp better then ncore500 and purifi 1et400a. Even better then my SE FU13 tube amp.

 

[solderdude]

Looks nice.

It appears as though the output is allowed to have up to 12V DC (which can destroy woofers) on it and relies on the power supply to be able to shut down its all its outputs fast it seems.

I assume this is to prevent a relay in the output (which usually are trouble makers so understandable).
Perhaps the UPC1237 circuit could be a more secure protection ?

At what output level, frequency and load did you measure -127dB residual ?

 

[Koifarm]

The DC protection is a copy from Hypex UCD and Ncore class-D modules who use the same power supplies.
This works for thousands of amps. Proven concept.

Yes you can use UPC1237 with relais but more complex with SMPS(No AC input)

But see first rule , proven concept for many years.

THD is measured with 1khz at 2,83Vrms(1watt)/8ohm. 0db ref is 0,775Vrms.

 

[Hayk]

Why you don't show your circuit in more conventional form using higher quality transistors.

 

[Koifarm]

Hello Hayk, thank you for your input.

I have changed powersupply path to make it shorter. Will test it next batch of PCB’s

The good thing of my circuit is excellent specs and the sound I like best until yet.
I followed the conventional path to long(40 years). There are now other options because of different components.
And the result is this amp. Nothing really new but a right combination.

The opamp in this circuit correct the flaws(if there) of the circuit behind it.

Gerbers for T-rex 5c, input and power PCB as attachment.