I have 5 sets of non-diy speakers with drivers ranging from 5 to 15 inches and they all reproduce acceptable audio when connected to the various Chinese built D-amps I have purchased over the last little while. To my ears, it is the swopping between speakers and not the amps that makes the difference.
I wonder whatever happened to tone controls? Back then it was simple to tailor the sound to suit ones own taste or system.
Just a thought.
And not a well thought out one at that.
You are as always, and I suspect deliberately, missing the entire point of trying to pin point common listening impressions from various sources listening over various systems, in that gives a good indication on where to start looking for limitations in a particular design and possible routes to optimize a design.
And tone controls? Don't even get me started on how bad an idea that is.
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Decided to bite the bullet and bought one of the finished amps with the adjustable subwoofer frequency. 2.1 HIFI digital amplifier board TPA3116D2 HIFI beyond TPA3123 TDA2030 LM1875-in Amplifier from Consumer Electronics on Aliexpress.com I don't see how I could have fashioned my own enclosure and all for anywhere close to the same price. Hoping it lives up to expectations compared to the tripath Dayton DTA-100a.
For one, it ain't that easy or cheap, to make an automated analog tone control. Same as with loudness contours. If you know of a cheap way, please let me know.
As for manual analog tone controls(baxandall), speakers are so much better these days, no need to compensate using tone controls.
I used to make/sell parametric eq's, parts are still sitting in a box.
My portable, using a Maxim MAX9729 has only bass boost and no treble control. I find it a minimum feature set.
Same as a balance control, anyone really use it? I only use it to test to see if the the speakers are working.
Tone controls are not inherently bad!
They are only bad when you want to get the best out of your setup, and have a clear sound as close to reality as possible, and this might not be the aim of everyone.
Just like judging the sound quality of an amp when listening to some FM radio station.
Regards
Nick
Well, as I said, I do not have the skills.
But judging by previous PCB GB's I've been part of and the cost of the boards vs their size, I would think that 50$ is a bit steep.
This is why I say I'd prefer to mod one of the existing amp designs over producing a new. If we're talking amps that are so generic they have to suit a lot of people, you simply end up with a different but much more expensive mass market design. It is not a viable concept.
Instead you can redesign everything from the ground up with a specific purpose in mind and that will be more expensive but it will also be much more attractive to the market it was designed for.
Instead you can redesign everything from the ground up with a specific purpose in mind and that will be more expensive but it will also be much more attractive to the market it was designed for.
PCB costs(Seeedstudio, pcb size 5cm x 10cm): $23.90 for 10 pieces (excluding shipping)
PCB cost: $2.39 (excluding shipping)
So what exactly do you mean by a "blank pcb for $50"?
On top of that, the TPA3116 is $2.20 (1000 pieces from TI)
So that leaves the rest of the components which I estimate on about $10 to $30 depending on the quality you want.
But this is not yet assembled of course. But I bet that once chinese manufacturers start to produce it, it'll be about $20 total just like the yuan-jing and feixiang amps. (when the same low quality components are used of course)
I can help you with software if you want. (off topic
)Only by collaboration many great things have been achieved!
Arduino is easy to use. You don't have to be a software geek. It enables fast prototyping and enables a lot of users to easily modify it.
The same can be applied to amplifiers. People are willing to pay if it gives them high-quality and if it is easy to modify to their needs.
For you it's cheaper of course, but please think in high-volume.
Same as above, think in high-volume. I think it's cheaper that you have one main pcb and can attach different kind of modules. When looking at yuan-jing, they have multiple versions of the TPA3116 amp.
About your SI4770, you might want to consider a KeyStone module(T1-L4A-8290C) which receives DAB+. Digital radio is becoming more and more interesting. And this module is simply amazing considering it's price:
10pcs --> $10/piece
100pcs --> $9/piece
1000pcs --> $8/piece
If you need an interesting (refreshing) project, consider DAB+ if you haven't already. It also received FM, FM-RDS and a lot of channel/station data.
Off-topic: Since I am quite new, and you must have no idea who I am, let me explain. I am a 4th years Electrical Engineering student. I have been interested in class-D amplifiers since I bought a TA2024 amp 3 years back. I have tested PAM8403 amps, PAM8610 amps and various TI and ST class-D amps.
I have a slight preference for embedded code and computer software code. (writing C and C# code)
If anyone needs help, please let me know!
Economics of designing a class "D" PA
I hear you about electronic design economics, but for me to make two 30 sq in pcb, 4 layer pcb, it cost me $50.00 USD each. I needed 4 layers because of the component density, need quiet grounds, since it a very sensitive radio with many clock sources, including a class "D" PA.
I understand how they "Asia" can can offer these products for the prices they do. It is hard to compete unless you follow their mfg model. Last job I was at, we brought electronic ballasts over by ship, in containers. Every penny counted if you want to under cut the likes of Philips/Panasonic at their own game.
I looked up KeyStone module(T1-L4A-8290C), good information
The size of the BGA chip is 8mm*11mm
Sure, perfect for DIY, The modules are interesting but no doc's, must have to sign a NDA = good luck unless you want to buy 1000's. I would think not very good for DIY.
I was just talking to my old R&D boss from HP and he was interested as well, in my stuff. He is using same Atmel platform and writing code in C for his sail boat instrumentation, communications
We have no DAB in the North American market, so I have nothing to even test it with, unless I buy an expensive R/S SG. So not very interested in that at this time. I'll put it together with HD FM radio.
But to get this on topic again, I suggest that people do contribute to make there own Class "D" PA's, using these fine TI chips. Once you get some good libraries, it is not too hard to use Eagle to design up what you want and do a group buy, if you find enough interest, people can agree with feature set, just like user "OPC" is doing,with his wire stuff.
How's your SMT soldering skills? Teaching you that skill set at University
Cheers for the Holiday Season
Rick
I hear you about electronic design economics, but for me to make two 30 sq in pcb, 4 layer pcb, it cost me $50.00 USD each. I needed 4 layers because of the component density, need quiet grounds, since it a very sensitive radio with many clock sources, including a class "D" PA.
I understand how they "Asia" can can offer these products for the prices they do. It is hard to compete unless you follow their mfg model. Last job I was at, we brought electronic ballasts over by ship, in containers. Every penny counted if you want to under cut the likes of Philips/Panasonic at their own game.
I looked up KeyStone module(T1-L4A-8290C), good information
The size of the BGA chip is 8mm*11mm
Sure, perfect for DIY
, The modules are interesting but no doc's, must have to sign a NDA = good luck unless you want to buy 1000's. I would think not very good for DIY.Good stuff. Good luck in your school/career.
I was just talking to my old R&D boss from HP and he was interested as well, in my stuff. He is using same Atmel platform and writing code in C for his sail boat instrumentation, communications
We have no DAB in the North American market, so I have nothing to even test it with, unless I buy an expensive R/S SG. So not very interested in that at this time. I'll put it together with HD FM radio.
But to get this on topic again, I suggest that people do contribute to make there own Class "D" PA's, using these fine TI chips. Once you get some good libraries, it is not too hard to use Eagle to design up what you want and do a group buy, if you find enough interest, people can agree with feature set, just like user "OPC" is doing,with his wire stuff.
How's your SMT soldering skills? Teaching you that skill set at University
Cheers for the Holiday Season
Rick
So one of these should be perfect? 12V 5AH Sealed Lead Acid Batteries (12 Volts 5 AmpH) - High quality and lowest price guaranteed
Or would you recommend something else?
As many of you know, I learned how to solder SMT the hard way with my deadbug TPA3118D2. Soldering the 0.6mm pitch pins to 26 ga wire wrap wire was very rough going and I don't recommend it. Might have been easier with a tiny solder tip but I used what I had. Conversely, with a real PCB, I found soldering that to be very straightforward. There are few tricks that you can get watching youtube videos on how to do it. Once is tack the corner pins first then solder the rest. The other is to hold the caps or resistors down with the tip of the metal tweezer while tacking one end. Then solder both ends. It was quite fun actually. The PCB that Dug provided me was a joy to work with compared to the deadbug I made.
Regarding costs: Itead.com will sell you 10 boards for $10 if you can squeeze your circuit into 2 layers x 2 in x 2in. Shipping included. How do they do it? Must be a robot making that thing...
Regarding costs: Itead.com will sell you 10 boards for $10 if you can squeeze your circuit into 2 layers x 2 in x 2in. Shipping included. How do they do it? Must be a robot making that thing...
Or this one as power supply:
http://www.ebay.com/itm/EU-plug-9800mAh-DC-12V-Super-Rechargeable-Lithium-ion-Battery-SPC-2261-/291020210533?pt=UK_ConsumerElectronics_Batteries_SM&hash=item43c2280165
Cant link but it is a 12v lithium 9800mah. Someone that could estimate how many hours that one works on the tpa3116, should be quite a few?
http://www.ebay.com/itm/EU-plug-9800mAh-DC-12V-Super-Rechargeable-Lithium-ion-Battery-SPC-2261-/291020210533?pt=UK_ConsumerElectronics_Batteries_SM&hash=item43c2280165
Cant link but it is a 12v lithium 9800mah. Someone that could estimate how many hours that one works on the tpa3116, should be quite a few?
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Maybe this is a stupid question but ok I'm not up to speed on a few things when it comes to power supplies ... so, if one is looking at 12v batteries what would be the difference with this amp between those rated at 4.5amp vs 5amp vs 5.5amp vs 6amp? Thanks for whoever can educate me a bit on this.
Batteries are rated in volts & ampere/hours, which means that a 4.5A/hr battery will have the capacity to deliver 4.5A for one hour or it can be scaled. An example to is for above to be 0.45A for 10 hours. These are approximate numbers, used to be a guide.
http://www.itead.com/ Bad Request (Invalid Hostname)
As far as how long it would last, just need to figure out your load current and do some simple algebra.
9600mA/hr, TPA3116 draws say average 500mA = 19.2hours
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As far as how long it would last, just need to figure out your load current and do some simple algebra.
9600mA/hr, TPA3116 draws say average 500mA = 19.2hours
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As long as it's an SLA or LFP battery it really doesn't matter too much what the specific capacity is. It'll have effect on the battery life time as nominal capacity on the battery is measured at 20 hour drain times. Shorter drain times, ie. higher power consumption than used to measure the battery's capacity, will lower the capacity in a non-linear fashion.
Do not use li-ion or li-po batteries to power power amplifiers.