Sam, I can't thank you enough for sharing this and everything you do for all of us ! P.S.: Happy New Year brother !

@boonesimon3712

2 жыл бұрын

Instablaster...

Very nice Sam! Had 3 B2 Riot 7k's on my bench that this would have been handy for. No more scary powerups for me. Thanks very much!

Hey I just wanted to say I really enjoy watching the Streammas VODs (as well as your regular content :D)!

Great video. I saw you using this in another as well, but this explains it better

Happy new year brudda! Thanks for the info :)

i've said it before - your explanations are very good. i learn lots

Sam, used the same method to separate high voltage and low voltage to rails for safety work on GZCA 35K SPL. The best method to work on this type amplifiers. One jumper for HV on PSU, and another for only drive section.

I have seen voltage injection in PC board's this is very similar and cool,nice work!

Very awesome technique indeed! 👍🏻

i imagine that if the output section is shorted they cook the board with this initial 12v, the firsts taramps "platinium series" had this problem in the past, thanks for the vídeo.

Yo, thanks a TON for your videos, I have learned so much!! I have a question about voltage injection, would it be possible to supply the +/- rails off a battery pack? like +/- 80V directly?

Happy new year Sam and good to see you again! What do you think about In Phase amplifier IPA4001D ? I ask because i hear a lots of negative thinking about In Phase

@barevids

3 жыл бұрын

It's a pretty poor inefficient 2k amp ☺

🙏 thanks for sharing your knowledge

Sorry I have missed most of your livestreams lately. Miss the videos buddy.

That top mosfet driver (at the beginning) looks like it has a hole in it where the magic smoke escaped! Also, you can use the power supply itself to vary the rail voltage. Just replace one of the resistors in the resistive divider that feeds back to the power supply controller with a pot. As you said, the feedback pin looks for a constant voltage, and once that's achieved, then it stops pumping the power supply essentially. With a pot in the resistive divider, you can change at what rail voltage the feedback pin sees the voltage it wants, and there you have a built in adjustable rail supply! I guess as you mentioned in another comment, that might not give you a huge range on the rail, but it depends on the controller. Some switching controllers can go into pulse skip mode to achieve lower voltages, or when the load (current draw) is really low. They only pulse the boost circuit when the DC rail falls below the target.

@barevids

3 жыл бұрын

That's not correct I'm afraid buddy, the power supply fets are supplied with PWM at all times of course, in order to supply current to the output section. Even with the deadtime set to extremely high, the voltage on the rails is still exactly the same. The only way is with an external rail supply. There is no way to use the original power supply section to vary the rail voltage.

@gorak9000

3 жыл бұрын

@@barevids What are the part numbers of the mosfet gate driver you removed, and the switching controller where you fool the feedback temporarily? I'd be interested in looking at the datasheets of those... every switching controller I've ever run across sets the output voltage by using a voltage divider to a feedback pin.

Great great video. Laughed so hard at "if there's any ladies watching....definitely not...who the hell...anyway" :D :D :D :D :D Instead of doing this with the donor board for the +rail voltage, another bench power supply can be used to supply 0-100v. No need of big Amps. Additionally You are using the overcurrent protection of it ;)

@barevids

3 жыл бұрын

Yes very true! I would need a supply with a middle point ground reference though. I find that when I have just hung a. Single ended DC supply across - rail to + rail, it often shifts over time due to uneven current draw from both rails. But yes, that is the eventual solution.

hey man i just picked up a vfl 750.1, it is blown and im currently working on it, has no lights on it, no power or protect, few mosfets were blown at the output section, i took them out and hooked it up to a 12v supply i have, it draws maximum amperage and then after a loud click from the amp it goes down to about 2 amps, still no lights thoe, any idea on where i should go from here?

You once started repapairing that older version of SD 8k 2ohm but you had wrong fets. Did you get it up and running eventually?

@barevids

3 жыл бұрын

Still waiting to finish it 😂

@barevids I have a power 1000 chrome rf amp. It hasn’t been powered in 15+ years. The PCB is newer than the amp as RF replaced it for the last factory one years ago. What’s the best way to power it up or test it? I’m uk based so it could go to you? It was working fine last time it was used. Cheers 🤘🏻😀

@barevids

3 жыл бұрын

Use a low current power supply, between 4 and 10 amps if possible 😎

@curranhouse

3 жыл бұрын

@@barevids brilliant thanks Sam. I will put it on a bench psu and current limit it. Cheers :)

Would you be able to work on a Soundstream reference class A amp from the late '90s?

@barevids

3 жыл бұрын

Yes

@johnnsteele2886

3 жыл бұрын

@@barevids How would I go about that? I haven't powered it up in years and someone did a poor soldering job on the fuse at some point. I would love to know how much you charge for a once over. I'd like to know if it is healthy before installing it. It might be a good idea to recap it. I'm certainly not confident, and I respect you and your knowledge and you sharing it.

@barevids

3 жыл бұрын

Shoot me a message to my facebook page facebook.com/nsvaudio

Why would my b2 16k clip light be blinking when volume is turned up with the gain is a 1/4 way up

@barevids

Жыл бұрын

Because you're clipping. Turn the lpf to minimum and add 55hz lpf on the head unit.

Buenas que mofet usa en etapa de audio

Wow

Im so excite

@b1rken

3 жыл бұрын

and I just can't hide it

@Bassotronics

3 жыл бұрын

And I know, I know, I know, I know, I know I want you, I want you!

Hello, can you help me? I would like to know what is the mark D1 piece. ampli TRF SMD 15000.1D . thankyou

@barevids

Жыл бұрын

Irfp4227 but you should consider replacing with IGBT or 4229

I wonder if you could use a transformer on a lower voltage higher current bench supply, rather than buying a 200v bench supply

@barevids

3 жыл бұрын

That's exactly what I've done here haha. Remember bench supply is DC. Transformer needs AC. So we use switching supply of a spare amp tand it's transformers to step up voltage.

Why not for the Frankenstein power supply amp thing just adjust the feedback divider of the power supply controller circuit

@barevids

3 жыл бұрын

The only thing we can adjust is the deadtime on output of tl494 which won't give us variable voltage from 0 to 116 😔

I have a sundown sfb 3000 it's I guess China Brazilian board the speaker outputs for the sub is putting out DC voltage I don't know what I should replace on the amp I don't know if my repair guy in my city knows how to fix these kind of amps

@barevids

3 жыл бұрын

This is totally normal. That's how they're designed. The speaker terminals will have around half rail voltage DC at all times. Even when the amps off.

@krazydogg7685

3 жыл бұрын

@@barevids no I mean the app was working good for a while and now it's not when I hook up a sub to the speaker I'll put the sub pushes all the way out and stays that way

Sir do you try a monoblock car amp convert into fullrange??? Waiting your vedeo

@barevids

3 жыл бұрын

You can do this already, just use slave input and it bypasses the pre-amp, it's as full range as possible from the components inside

@musicchannel-fr9zq

3 жыл бұрын

@@barevids i plan to convert my mono amp to fullrange.. I have no idea how to pix .. Please Advice me sir.. Need actual vedeo ...thank u

@musicchannel-fr9zq

3 жыл бұрын

I need sample vedeo... I hope you help me sir

Do u have a way to contact you I have a rf t3000.1 t800.4 and t1500.1 than need love

I wondered how you were poking around without getting zapped.

So it would be 12 volts and not 6 volts positive and 12 volts negative? Sorry I know this comment is wrong.

It would be cool to see you tidy that up into a stand alone high voltage dc power supply with its own voltage and current display. I think it could be done for pretty inexpensively, maybe even mount the high voltage portion of the power supply remotely so it doesn’t take up so much workspace.

@barevids

3 жыл бұрын

Yeah definitely, that's the plan now going forward. This was mostly a proof of concept.

What are "Korean Halfbridges"???

@barevids

3 жыл бұрын

In Korea they started building a bunch of bridges but ran out of money halfway through. So now there's a bunch of half bridges in Korea.

@matthiasmartin1975

3 жыл бұрын

@@barevids How depressing. But, really, i did try google.

i was sleeping

Seen a little of this yesterday and it cut out

Well i guess 6 volts to 0 and another 6 volts negative? I have had a pretty boozy night. I guess I am right on this comment.