I enjoy and appreciate your thoroughness and preparation for these videos. I always learn something from them.

@KissAnalog

3 жыл бұрын

Thank you! I appreciate you!

HI Eddie, Your videos are awesome and I like your thorough reviews. Thank you.

@KissAnalog

3 жыл бұрын

I appreciate that! Thank you!

Great evulation on amplifier design 👏👌 Thank you dear for very expensive reviews , lab tests and explanation 🙏💝💞

@KissAnalog

3 жыл бұрын

My pleasure 😊

Thank you Eddie.Great video as always.🥰🥰

@KissAnalog

2 жыл бұрын

Thanks so much!

Thanks for the videos. I'm really enjoying them. There are quite a few commercial active speakers that make use of these ic's (Wharfedale, dBTechnologies & even JBL).dB Technologies make some active 12 & 15inch speaker that use 2 in BTL, one driving the low freq driver, the other driving the tops (total overkill for the tops, they do reduce the output to the tops though). Great class d modules. Something of interest is that in order to run 2 8954's together in bridge mode, both modules need to sync to an external clock in order to avoid beat tones (datasheet.) The dBTech speakers used a very interesting way of creating an external clock using a triple gate inverter with just 2 timing resistors & a capacitor. Anyway, keep up the great content.

@arthureschner9319

3 жыл бұрын

Oh I almost forgot, the dBTech speakers where using +-40v for power supply. And those speakers kick some serious ass!!

@KissAnalog

3 жыл бұрын

Wow - thanks for the great feedback! That's great background! Those are great companies too, so that's a confidence builder.

@KissAnalog

3 жыл бұрын

Thank you! Sounds like they are getting the most out of the device;)

Love your videos but gonna have to watch a lot of your videos to get caught up 😂. I've only got the Air Force electronic principles brain

@KissAnalog

2 жыл бұрын

LOL thanks for your support!

Okey first off thanks for putting extreme effort into your videos! I bought near identical amp, but it states on the sellers page 24vAC up to 28vAC.. but it seems like all components can handle more.. Im guessing you are in this video putting 31v AC x2 in correct? i was planning to upgrade an old power amp with this board but that gives out 36V AC(messured with the amplifier turned on with no input signal or speakers connected) from the 2 orange and 1 black.. its rated at 230v and 365Watt(lable on the back of the amp).

@KissAnalog

2 жыл бұрын

Thanks so much! I used DC Power supplies so I could simplify the test. I used 31 VDC rails, so this would be the peak (minus some ripple) of an AC voltage of about 22 Vrms. I think they recommend 26 Vrms as the max ac voltage which would give about 37VDC for the rails (42VDC is the max the device is rated for). Does this make sense?

I have watched all the Vids on this Amp. Thank You. I know you mentioned at one point about going with a 4ohm load. Did you or will you measure out?

@KissAnalog

7 ай бұрын

Thank you! Yes I will do a video very soon showing all the measurements;)

Wish the Uni-T would send out a replacement button to change Mode to Mod as that is the modulation button. Love that inexpensive waveform generator. Use it all the time.

@KissAnalog

2 жыл бұрын

LOL - that generator really is pretty great - especially given the price;)

@isettech

2 жыл бұрын

@@KissAnalog I have not tested it for THD, but it seems to do quite well and I can't agree more on the price. I got the upscale one with the higher frequency. Really like that it can put out 20V P-P just fine.

@KissAnalog

2 жыл бұрын

Hard to beat and nice size;)

Another great video. I think a little too much is better than not enough. You can Always turn the volume down. Avoids clipping by over driving the Amp. My power supplies at home only go up to 30 volts as well. I was looking at Amazon today and DROK sells 48V 10A adjustable power supplies for 35 bucks each. They have an LED display on them. That is a steal if the output is accurate. I wanted to ask are you going to hook this amp up and use it? Probably be great for jamming to tunes in the backyard, cooking out.

@KissAnalog

3 жыл бұрын

Thanks Tron! I agree I think I like the idea of a little headroom. I'll have to look into the DROKs;)

Hi Eddie.As always great video.Looking forward to new videos.I have question about this amplifier board.I have same model but I use +/- 39v dc 500w supply.At high volume amp cuts sound for 1 or 2 seconds at one or both speakers.Look like some kind of protection.It does this only at high volume no matter if I use 4 or 8 ohm speaker,or no matter if I use 30w or 300w or 500w speaker.Overcurrent protection,clip protection ?

@KissAnalog

2 жыл бұрын

Thanks so much! Yes, this TDA8954 amp chip does have a lot of protection features, and an over current would shut it off but then allow an auto restart. Do you have lots of capacitance on the 39V rails? Have you checked with a scope to see if it is dipping?

@amin125ccm

2 жыл бұрын

@@KissAnalog no scope Eddie. No voltage drop at high load. Only capacitors are on amplifier board.Power supply board is type that converts 12v dc to +39 -39 v dc.

@amin125ccm

2 жыл бұрын

@@KissAnalog Sound is clean,and just starts to cut out so i have to turn volume down just a bit,but i feel like speakers can take more and amplifier should give more in comparison to my other amplifiers.

100W -125W seems to be on point for this chip, can't wait to see the outcome. Hopefully with a very nice PS...Cheers!

@KissAnalog

3 жыл бұрын

Thank you! I appreciate you!

It should do 336W at +-41V/8ohm and 376W at +-39V/6ohm with less than 1% distortion. As a bonus you can calculate the efficiency, which was supposed to be 93% according to datasheet. From your previous video I can see that number is way off.

@KissAnalog

3 жыл бұрын

Thanks for the feedback Ergin! I think I was getting close to that efficiency. At 200 Watts out and 93% efficiency, then I would need 215.5 Watts at the input. I had 64 V (2x32V), so then the current would have been 3.36 Amps. I thought it looked close but I didn't write it down. I think it was just above that but not much. I'll test this. Thanks!

Lots of power, but in HiFi terms THD is quite high and noisy fans that seam to run all the time. Would be better if the fan was on a 'on demand' bases. The question is what do they sound like? Do they have a sound? hopefully not. So far I think I will stick with my L12/2.

@KissAnalog

3 жыл бұрын

Thanks Michael! Sorry I was focusing on the power and mostly using the THD to see when the clipping started. I'll have to get a clean set up and consider the noise of the generator to give the Amp a fair THD measurement;)

although I enjoy watching,I do not have electrical background and about 90% goes completely over my head.

@KissAnalog

3 жыл бұрын

Thanks for this feedback. I wonder if I could do a video to help others like you understand what you are interested in - what do you think?

Do next one with Inductive loads Bz speaker Inductive behaviour kinds leads

@KissAnalog

3 жыл бұрын

Great idea - thanks!

@sunuk1915

3 жыл бұрын

@@KissAnalog welcome dear

Are you sure it is TDA8945 15w mono BTL ? May be TDA8954, no?

@KissAnalog

3 жыл бұрын

Thank you for seeing that;) I corrected it. Late night I guess;)

When I think of 200 W or 400 W when using a pair of Klipsch LaScala’s. OK when you use the very FIRST WATT you have 106 db. What do you do with the other 199 watts or 399 watts. I guess that’s just extra headroom lol 😂

@antibrevity

3 жыл бұрын

The brochure says 104dB 1w/1m for a LaScala. Mathematically, you'd be able to produce about 130dB with 200W to each speaker and maybe 136dB with two of them. However, the speaker can only handle 100W continuous and is thus "only" rated to produce 124dB at 100w/1m. That's still high enough to damage the hearing of anyone nearby in mere seconds, so I don't recommend trying it ;).

@coldfinger459sub0

3 жыл бұрын

@@antibrevity are use my sound meter because I was curious what do I like at a moderately high comfortable enjoyment level. For me it’s around 83 DB with 97 DB spikes. 104db or 106db at that loudness I’m not even going to notice the difference of 2db. @ 1w/1m Even hooking my Nelson Pass ( Amp Camp Amp) Version 1 that only has 4 W to my DYI Fostek Single full range driver 8 inch backloaded horn cabinet 96db rated. Just driving one watt of power out of that 4 Watt class A amplifier was way more than enough. I had to turn it down to about 3/4 of a watt to be comfortable When I hook that 4 watt amp up to a signal generator and I found it resonance frequency inside my room the drywall was shaking the dishes in the cabinet were shaking and my neighbor asked me what the hell was I doing at about 49 Hz. Yep 1 W is too much

@KissAnalog

3 жыл бұрын

Thanks! great point!

@coldfinger459sub0

3 жыл бұрын

@@KissAnalog But I am all for more is better bigger power supply bigger amplifier

@KissAnalog

3 жыл бұрын

@t lech that’s really great info - thank you!

36 volts or 40 volts not much difference in distortion you'll never hit that 10% if you don't drive the app that high on 40v

@KissAnalog

3 жыл бұрын

Thanks David! Great point!

Way over my pay grade

@KissAnalog

3 жыл бұрын

LOL I hope there's something that you can gain from this;)