Yes indeed, Neville Thiele (aka A. Neville Thiele) is credited with the category of circuitry under discussion.
He is also credited with the separate work called Theile/Small; it relates to methods for simulating behavior of woofers (low frequency audio electromechanical transducers)
see https://en.wikipedia.org/wiki/Thiele/Small
He is also credited with the separate work called Theile/Small; it relates to methods for simulating behavior of woofers (low frequency audio electromechanical transducers)
see https://en.wikipedia.org/wiki/Thiele/Small
Thanks!
Also would you like to suggest other room for improvement for the Parallel TDA7293 amplifier?
Basically, AndrewT said to Bring It!
I tried it and it wasn't boring in any aspect.
That tech went a bit excessive, but I was glad to learn what it could do.
I've got to say that I appreciate the non-boring experience.
Perhaps we should see what a smaller scale does?
That was too much. Worked fine, but that is not the right size for a house.
I'm never doing that again.
I tried it and it wasn't boring in any aspect.
That tech went a bit excessive, but I was glad to learn what it could do.
I've got to say that I appreciate the non-boring experience.
Perhaps we should see what a smaller scale does?
That was too much. Worked fine, but that is not the right size for a house.
I'm never doing that again.
Single supply?
the TDA7293 found wide use in low priced 5 channel receivers and in cheap active speakers. Thus there were plenty of professional measurements published in audio magazines which shows these amps are lower middle class .
But that may be as good as and no worse than many far more expensive diy amps. To make it even more cheaper .... if the amp board could run from single supply that could save the insulator chip which is required for heatsink mount as pin 8 is connected to tab which is then power supply ground that saves up to 1°/watt thermal resistance and the heatsink can be smaller accordingly
getting cheaper day by day...
the TDA7293 found wide use in low priced 5 channel receivers and in cheap active speakers. Thus there were plenty of professional measurements published in audio magazines which shows these amps are lower middle class .
But that may be as good as and no worse than many far more expensive diy amps. To make it even more cheaper .... if the amp board could run from single supply that could save the insulator chip which is required for heatsink mount as pin 8 is connected to tab which is then power supply ground that saves up to 1°/watt thermal resistance and the heatsink can be smaller accordingly
Maximized cost-effectiveness is not found here, and thus the proletariat would be best served by avoiding this thread.
However, a bit of listening would probably work alright.
The performance may arrive in the middle (and possibly pleasant too), unless you under-volt to improve the linearity for unlocking high end potential. The usage may vary like that. Hopefully, any linear amplifier will do just like that. That is sort of what the word linear means.
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Oh, that's true!
Also true that this chip is rarely used for high end audio, but typically used for inexpensive low-fi appliances. The capacity for either job is present. However, I think that the typical use will affect the odds on the reviews.
It can be a bit expensive and time consuming to make this chip do hi-fi. Both problems are quickly solved by aiming lower on the voltage and wattage.
What I need for my speakers and my house, is more than 25 watts, less than 45 watts. Since I have 8 ohm speakers, I need more than an 18-0-18vac transformer, less than a 22-0-22vac transformer. A 4A 20-0-20vac transformer would do. This lower voltage and the lower watts from the amplifier, will let me set the gain lower for higher resolution without giving up the feature of a pretty tone. Still similar, the power parts are only about $10 cheaper. So much less waste heat is produced (aka Far more efficient) that I can use a smaller and less expensive heatsink and enclosure--I guess that is about $40 cheaper. The news was that it cost about $50 less to make it a hi-fi.
The magazine people probably didn't want to hear that hi-fi is cheaper and more efficient.
Hi folks. Just looking at these kits TDA7293 x2pcs 170W Mono amplifier board Kit | eBay as mentioned in the first post - has anyone ordered lately and is able to vouch for the chips being genuine? Seems to cheap to be true. Cheers!
TDA7293 version 6, are usually slightly less than $2 each in small lots. So far, the advanced feature set with all of the pins working, has not been successfully faked. The chips on the board that you refer to are TDA7293's. That particular variant is not rated for the maximum voltage listed in the datasheet but can be used along with your 25+25vac transformer and adequate power board. It is the same chip that ships from Mouser. That is the current part.
Hi,
Got two of these boards on the way to compare to my TA2022( and TA2022 in BTL should I get the DC-offset issue under control on my two extra boards).
TDA7293:
I've got some of the upgrade/mod parts on the way as well, in fact they'll get here well before the TDA7293 parallel (mono) boards.
I got the ones from the first, IIRC, post in this thread.
I have two toroidal transformers that are suitable, one is 0-24/0-24VAC 300VA, the other is 500VA.
As for cap bank/rectifying, I was thinking:
MUR160 or similar with 100nF wimas across them
2x4700uF + 1x3300uF per rail OR 1x10000uf + 2x4700uF per rail.
A bit off-topic maybe...but would the TA2022 EV-board DC-servo circuit work on a TA2022 board in BTL?
Got two of these boards on the way to compare to my TA2022( and TA2022 in BTL should I get the DC-offset issue under control on my two extra boards).
TDA7293:
I've got some of the upgrade/mod parts on the way as well, in fact they'll get here well before the TDA7293 parallel (mono) boards.
I got the ones from the first, IIRC, post in this thread.
I have two toroidal transformers that are suitable, one is 0-24/0-24VAC 300VA, the other is 500VA.
As for cap bank/rectifying, I was thinking:
MUR160 or similar with 100nF wimas across them
2x4700uF + 1x3300uF per rail OR 1x10000uf + 2x4700uF per rail.
A bit off-topic maybe...but would the TA2022 EV-board DC-servo circuit work on a TA2022 board in BTL?
. . . The TDA8932 is capable of the highest of the highest current current delivery of the series; and, therefore, you might want to get the values within approximate specs. It works fine if one has some sense. However, in any case, feel free to ask.
I'm sorry, I'm not following.
TDA8932?
Anyway, after looking at the EV-board schematic, I think I'll do a layout for the DC-servo part in eagle. To much going on there to be easily perf board built.
Back to the TDA7293, Would the 300VA toroid be enough or should I go for the 500VA? Both are dual 24VAC.
The amp will drive two Dayton 15" IB in Dipole (one per channel).
Thanks, I thought it might be.
I'll have fun comparing the TDA7293 parallel mono boards to two TA2022 boards in BTL, when I get the DC-offset issue sorted on those.
Please describe how it broke down so that I can phone for relevant help if need be. I rarely ask; but, it it had gone down then I need to know the details so that I can ask people smarter than me. I'll do it too, and those guys know it. Just please document the breakdown as well as you can. Thanks!
If I can't do it, then I will pass on the parameters to someone who can. Do please explain what the need is. This matter will be resolved.
I'm currently working on transitioning from tech to engineer. Sure I can make really well working PCB's without fail; however, they won't be convenient. That's going to take more study. You'd be well served by not making a PCB from me at this time.
First off, on one of the boards, one of the resistors blew. The one that's supposed to be a zener on the PCB, and comes pre-soldered on the board.
I solved that by putting some 1W resistor in parallel to get the same value.
But both boards(the ones not in use) has too high DC-offset.
I think it may be down to poor tolerances on some of the resistors included in the kits.
I have collected the parts needed to make a DC-servo/relay board as per the evaluation boards documentation.
I'm deciding if it is practical to perf board it, or if I should get boards made.
I've got a preliminary, let's call it a beta version, of a layout done in eagle.
I also need to figure out if it's ok to run the TA2022 boards as BTL with the DC-servo.
As for the TDA7293. no issues there as I haven't recieved the kits yet.
I have recieved the parts needed to make the suggested mods, and I have the parts for a rather big capacitor bank that the boards will share.
I have not recommended any zener for this amplifier, as is evident by my published schematics.
In fact, I have simplified the matter so that you don't have either the breakage or the zener.
I have a slightly bulky cap array arrangement for that task, but I have not recommended a DC servo as is evident by my published schematics.
Very irritated! It is not recommended to install additional distortion.
I sure do understand that part of your comment. Yes, the TDA7293 can get readily informative about its needs. It will be convenient if you don't install mixed advices from the whole of the internet into just one amplifier.
And, in fact, if you're not making mine, then your adventure needs a thread of its own.
Even though that need is likely, also I understand, and also you are plenty welcome to post anything about a TDA7293 on this thread.
But, as for mine, please attempt to build it on spec and report back after having done so.
Well, I'm alarmed and I'm trying not to complain too much; but, it is very difficult to help you if you make a random thing without an expected function.