Maximum output with tda2050

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I build amp tda2050 with esp project with 25V +,- split power supply. I want maximum output as possible to 2050.

1) If bridge, please post schematic.

2) If it is possible to alter esp project. For exmple remove input addtional components, which is not in datasheet.

3) In Esp's project, If I remove 100uf caps to minimize components and depend on power supply caps.

4) I have replaced 1K feedback resistor with 340 R.

5) Used two 4ohms speaker to increase loudness.

6) I used 4700uf for (+) and 4700uf for (-) caps at power supply. Should I increase ?

7) Or alter any output caps & resistor which is connected to ground.

Please help, Thanks & Regards.
 
I am sorry. As I understood, I going beyond the limits of tda2050. My experiments may not long lasting, so I am going to limit the circuit gain=23 and Single Speaker 4 Ohms load only. I did not find bride circuit for 2050, not even in the datasheet, so I should forget and listen mono IC only. Sorry again.

Thank you, Regards.
 
pra3718 said:
I am sorry. As I understood, I going beyond the limits of tda2050. My experiments may not long lasting, so I am going to limit the circuit gain=23 and Single Speaker 4 Ohms load only. I did not find bride circuit for 2050, not even in the datasheet, so I should forget and listen mono IC only.
The bridge circuit is in the TDA2030's datasheet. Keep in mind that each IC in a bridged configuration sees half the impedance. Your 2x4 Ohm in parallel will appear as a 1 Ohm load for each TDA. If the ICs survive at all, they will sound terrible due to increased distortion.

The better solution is to use a dedicated amplifier for each driver. That leaves you with the same amount of components and with two amplifiers driven within their specifications.

Use the LM3875/3886 or TDA7293/7294 instead of the TDA2050, if you want more power.
 
pacificblue said:
Your 2x4 Ohm in parallel will appear as a 1 Ohm load for each TDA. If the ICs survive at all, they will sound terrible due to increased distortion.

Back in my Linear Power days, I used to beat the snot out of TDA2040s and while they didn't sound too hot, their internal SOA protection system worked flawlessly. I always thought they were pretty robust little chips. I still have a handful of them, but never put them into action.

If you have some, replace your TDA2030s and see how it works. Nothing ventured, nothing gained. . .

Regards,
Paul
 
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In one of your earlier threads, you stated that SQ was more important than power, and today we're back at Square One. :sigh:

Just get eight TDA 7294 chips, and bridge-parallel them. They will survive all your macabre experiments without batting an eyelid. Be sure to have a very large heatsink and power supply handy. It's cool, I did the same thing with four LM4780 before realising that I was looking at the wrong end of the horse for a long time, and that a good 25 watts was much better than a lousy 250. Growing up in audio, I guess, one tends to do these kind of things.

@DCPreamp: I concur. I used four TDA 2030 in a bridged arrangement driving 4 ohm speakers at the supply limits (I think they were at 19V rails) for a long time. I also used them in inverting configuration, and being driven from a NAD CDP, which was looking into a 2K load almost all the time. I'm sure if I listen to that system today (R.I.P) I would not be able to stand it for a few minutes, but back in the day I thought it sounded fabulous.

The LM series will be difficult to find in India, they may not be available at all and you might need to import them. I buy mine from D-K or with the PCBs from the kit manufacturers. TDA 7294 is readily available in most local markets.
 
Sangram,

In one of your earlier threads, you stated that SQ was more important than power, and today we're back at Square One.

Yes, I was trying to improve sound quality with help of another amp. (2050). I build single tda2050 and found it is lounder. I listened carefully both 1554 & 2050 I found 1554 is more sharp & clear for mid & tweeter & 2050 is more louder and good for low frequencies. ( Or 2050 I could not tune for mid & tweeter ) I was worried about my subwoofer you know, my single supply preamp & 1554 power amp, I found single 2050 is better than ne5532+tda1554q combination.

Please try to understand that I am growing man in audio-electronics. And you know my all attempts very well.

I just copy ESP's tda2050 project which was correct build-up with first attempt. Only problem was low-output due to my weak sub-signal. a) As per stated in ESP & experienced member I listen with 4ohm single speaker. b) Just for trial I joined one more 4ohm speaker, I found bass become more louder & tighter c) Then I decided to increase gain (@pacificblue's post was about "adjusting the gain" Just plain logic, two 4ohm speaker can increase the gain then two 680 R resister can be more louder. And yes, circuit becomes more lounder.

1) Now Sub becomes more powerfull & tight bass than ne5532+tda1554q combination. (improved sound quality)

2) Power ON/OFF sound decreased to as nothing and acceptable now.

3) My dedicated-2050 heatsink size (3"x5") becomes very hot within 30 min.

4) Using two 4ohm speaker.

5) Overall it is sounding good. No problem at all.

Now Question is, how long I can listen this 2050 system ?

@Pacificblue: LM3875 is not available to my supplier right now. You are right If I want more power I should switch to high watts amp. But sad news is I have to manage with what is available to me, and I am trying the best out of it.

Thank you & Regards.
 
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@pra3718 - I don't mean to offend. You should step into a decent hifi shop (not a multibrand outlet with consumer electronics, a real Audio and HT shop) and listen to a few setups. I took a long time to figure it out, but the way we build stuff in the country is not how it is done. There are a few guys like Rethm, Audire and Cadence, but for the most part, it's all junk. Unless you actually hear some live music and some good setups you won't have a reference.

I'm just trying to save you some money. These incremental upgrades, spending a bit at a time to improve the subjective experience, is doing no favours to you or your setup, or indeed, your cash flow. First listen to a few good ones (at least ~150,000 INR) to understand a bit about how different systems sound. then you'll see what a good setup *should* sound like. Take a few CDs with you, of your own favorite music. I kid you not, you'll notice a huge difference.

From what I saw of your speakers, you will notice a huge improvement in overall clarity and the experience will help you go for a really good setup quickly. I have been through this cycle myself, my friend, and suffered for a long time with second-rate builds and products. Only after I started using the LM series did I actually manage halfway decent sound out of my amps. Also the passives you get in India are the worst sort. You never realise, until you use your first Panasonic FC or Nichicon Muse or even a Yageo resistor, how much of a difference it makes. How is a resistor offered at 25 paise (~USD 0.005) ever going to sound good?

Finally, on your chips - I see you're pushing the TDA 2050 to the edge. It was not meant to handle 2 ohm loads, but it'll survive. It probably sounds nasty but since it's for the sub, you'll likely not notice. Anyway 3x5 heatsink is way too small for the 2050, not surprised that it's heating up. I think PB earlier suggested two 2050, one for each 4 ohm speaker, with each chip on its own sink. That will reduce the load and help the poor chips relax a bit, with resultant reduction in distortion. I would recommend you immediately implement this.

TDA 7294 is easily available, as long as its genuine it can be used. It'll be 100 watts peak with 35 volt supplies. With 8 ohm loads (wiring two woofers in series will do this) you can even bridge the chips for power ~150 watts, and it does not sound inferior to the LM3875.

Edit: I know LM series is not available in India, but it's stocked by vendors like Digikey, Parts Express and Mouser. Just order 10 chips and you're set for a few years, and add some caps and quality resistors, and you can actually supply spares to people and recover your investment. That's what I did, though I haven't recovered my investment...

Good luck.
 
@Sangram,

The better solution is to use a dedicated amplifier for each driver. That leaves you with the same amount of components and with two amplifiers driven within their specifications.

I think PB earlier suggested two 2050, one for each 4 ohm speaker, with each chip on its own sink. That will reduce the load and help the poor chips relax a bit, with resultant reduction in distortion. I would recommend you immediately implement this.

After reading this two post, I should try for two 2050 within their specifications.

TDA2050 datasheet claims 50W. In which condition I should achive 50W output?

I have two power supply cables one is for DVD Player and another for my system. First I switch on for my system tda2050 Hammmmm sound starts and after swiching on for DVD Hammmmm sound quit.

Thank you & Regards.
 
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Classic ground loop. Connect both on the same outlet strip, and ensure the RCA input jacks are insulated from the chassis.

The 2050 is optimistic peak maximum, hardly the continuous output. 50 W is voltage x voltage /impedance, assuming the current output is within the chip limits. And voltage output = voltage input x gain, assuming the amplifier has the correct supply voltage.

Plug the numbers in, and you get 20V into 8ohms for 50W output, a trivial task for an amp with 50V rails. I do not know what the input voltage is, but assuming it is .775V line level, you need a gain of roughly 26, or ~30dB(?)
 
Finally, on your chips - I see you're pushing the TDA 2050 to the edge. It was not meant to handle 2 ohm loads, but it'll survive. It probably sounds nasty but since it's for the sub, you'll likely not notice. Anyway 3x5 heatsink is way too small for the 2050, not surprised that it's heating up. I think PB earlier suggested two 2050, one for each 4 ohm speaker, with each chip on its own sink. That will reduce the load and help the poor chips relax a bit, with resultant reduction in distortion. I would recommend you immediately implement this.

After listening for long time, I realise tda2050 is still working for 2 ohm loads with 64 gain. Infact I had altered esp's schematic for some reason which is as under.

1) Input impedance resistor 33K ( It was available to me.)
2) Feedback resistor 340 R insted of 680 R ( for increase gain )
3) Frequency stability caps : Two nos 100 nf
4) RF filtter skiped.

I realise that some song (music) sounds very-very good, but in some songs (specially classical) I found bass is tearing. Is that reason I have build this circuit out of limits ? Or, Is there any way to rectify it ?

Thank you & Regards.
 
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