Been following this thread with interest, and have to agree with radiosmuck, it has certainly gone off topic. These little lunch amps are amazing, either straight out of the box and or modified. Why would you want to spend 40 times the cost of the original on a concept amp???
This is a DIY forum, as far as I can see the "luxury gourmet dinner for two" amp is just a sales projection at the moment!
None of us can confirm the greatness of the amp, just by looking at a few pictures! How about making the PCB available, or the schematic, so someone else can try its merits (in the DIY spirit of course). Even the big boys of chipamp PCB's publish their circuit diagrams.
But hey what do I know, makes amusing reading anyway, when wire/cable is mentioned!
I don't sell cables, and can't afford anything terribly expensive, so I'll reserve myself to: yes I've heard some clear differences but I haven't investigated as I don't have a reason so I'll leave it up to whomever to do what they want at that bridge.
I did experience a harshness with mil-spec silver coated DIY IC's once, which matches what people say about the wire.
The fellow that is having a custom 7297 built by me is searching for new single ended cables, since he runs XLR now. But he said whether or not they offered an improvement for some qualities he'd like to enhance, my BJC IC and the amp as is would still be highly preferable to his Bryston.
The earliest word from the second stop on the tour was that the coherency and clarity of separation was noticeable at a quick listen before getting into it.
I did experience a harshness with mil-spec silver coated DIY IC's once, which matches what people say about the wire.
The fellow that is having a custom 7297 built by me is searching for new single ended cables, since he runs XLR now. But he said whether or not they offered an improvement for some qualities he'd like to enhance, my BJC IC and the amp as is would still be highly preferable to his Bryston.
The earliest word from the second stop on the tour was that the coherency and clarity of separation was noticeable at a quick listen before getting into it.
Exactly, let's get back to Lunchie!
Lunchie rockin (2 x 12V SLA) the storage locker 😀
[w Beta15, PR170, St8 tweets]
[at a chilly 2 o C, 35 o F]
Lunchie rockin the storage area (eventually got me 'silenced'! ... because ...)
... and I quote, from mangmnt, "No, no, no, no, no, no! No partying going on here!" [With 2 x 12V SLA batt!]
Lunchie in steree-ereo!
😱
Lunchie rockin (2 x 12V SLA) the storage locker 😀
[w Beta15, PR170, St8 tweets]
[at a chilly 2 o C, 35 o F]
Lunchie rockin the storage area (eventually got me 'silenced'! ... because ...)
... and I quote, from mangmnt, "No, no, no, no, no, no! No partying going on here!" [With 2 x 12V SLA batt!]
Lunchie in steree-ereo!
😱
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I'm not trying to "hawk" something by the way; you see me as some peddler merchant trying convince people they need what I have. What I'm doing is offering something really damn nice to the DIY crowd that can't often afford to buy into anything actually good. I've spent a bundle money I'll never see if I raise my crowd funding goal that only breaks me even on parts!
There's no debate about my amp having lower noise, you've only brought up distortion as a figure. It's not perception, you can look at the data sheet of the CMC, you can calculate the reduction in inductance, etc etc... it's readily apparent that it out performs the original and most power supplies used. The question not answered is what does that mean for sound? Hence the demo.
Someday hopefully I'll have commercial products, but I want to continue to offer stuff to the DIY community because I respect people that do things aside from pushing paper. But what I won't do is offer half-assed kinda ok blah blah like from China. Whatever I create for DIY is aimed to impress your friends who spend tens of thousands on gear, but not bleed you dry. My time and money is extensive towards my respect for the DIY community, so I don't appreciate the attitude. Save it for the peddler on the street that has to coercively convince you; I've sent a demo out so people will come to me asking for it instead of following you down the sidewalk.
AudioLapDance, that looks like fun to me! I love outside listening. For years I've wanted to an outside listening weekend out in the country with my old OB Hawthorne speakers. I decided I wanted to do that after we used them for my grandfathers eulogy outside... Frank Sinatra was like he was in real life, bigger than it!
Hi Guys
I have been impressed with my new TDA7297 so far and it is time to dust off my soldering iron.
I have removed caps ect and would also like to do away with the volume pot as well but am unsure which of the six contacts to bridge, can anyone help please?
Simon
I have been impressed with my new TDA7297 so far and it is time to dust off my soldering iron.
I have removed caps ect and would also like to do away with the volume pot as well but am unsure which of the six contacts to bridge, can anyone help please?
Simon
My unmodified lunch money amp get's left on permanently, and has been for the last 2 years, only adjusting the volume.
I'm using an inexpensive Muse 14v 4 amp brick and putting my ear up against the speaker grill, I hear nothing but dead silence, amazing!
I'm using an inexpensive Muse 14v 4 amp brick and putting my ear up against the speaker grill, I hear nothing but dead silence, amazing!
The pot pins, looking from the front, left to right, are ground, output, input.
With a DMM, and the pot turned all the way up, you should measure 0 ohms between the input and output.
After removing the pot, solder a wire between the middle and right holes on the front row...same for the back. You can leave the ground unconnected.
Hope this helps!
Mike
For doing without the volume pot:
Might want to bridge the Center-to-Input with 3k3 resistors and also bridge the Center-to-Ground with 47k resistors.
Separate bits for left and right, of course.
That will simulate the 50k pot at "almost all the way up" position. In this case, input to ground is really close to 50k, and that's probably better than no input load at all.
Might want to bridge the Center-to-Input with 3k3 resistors and also bridge the Center-to-Ground with 47k resistors.
Separate bits for left and right, of course.
That will simulate the 50k pot at "almost all the way up" position. In this case, input to ground is really close to 50k, and that's probably better than no input load at all.
Well Back to the lunch money amp ...
I added some output caps, and a power cap.
My son and I built a custom case
We are mid way through the speaker build.
As the say priceless getting the undivided attention of a 13 year old teen ager!
I added some output caps, and a power cap.
My son and I built a custom case
We are mid way through the speaker build.
As the say priceless getting the undivided attention of a 13 year old teen ager!
sounds great with my cheapo parts express dayton $50 cabinet test speakers.
Blows the little mono speaker in Sons internet radio right out of the room.
Big smiles all around!
Blows the little mono speaker in Sons internet radio right out of the room.
Big smiles all around!
Received this yesterday,
Free Shipping Bluetooth MP3 WMA Decoder Board 12V Wireless Audio Module USB TF Radio for CarA111-in Other Electronic Components from Electronic Components & Supplies on Aliexpress.com | Alibaba Group
It sounds just fine to me, but then again, I am quite happy with my stock lunch money amp!
I have been enjoying a toothless version of the above for almost 2 years for fm receiving.
I took mine out from the bin, maybe I'll make a case for the amp and this receiver.
Any data on the Bluetooth specs? I presume these things have a DAC somewhere?
Besides the Bluetooth module there's a 5V regulator (7805), an eeprom chip for storing settings I presume, there's the FM chip and the largest one that does all the business.
I traced the outputs to the big chip and I see the signal passing through a smd capacitor and then through a 1k resistor then it goes to the connector.
Maybe replace that cap with something larger? Also might be worth checking the value.
Let's not derail, maybe I'll make another thread on this trinket.
On the Bluetooth module I see connected to main pcb only ground/+V and two lines that I presume are left/right channels.
I traced the outputs to the big chip and I see the signal passing through a smd capacitor and then through a 1k resistor then it goes to the connector.
Maybe replace that cap with something larger? Also might be worth checking the value.
Let's not derail, maybe I'll make another thread on this trinket.
On the Bluetooth module I see connected to main pcb only ground/+V and two lines that I presume are left/right channels.
Hi, sorry for the reiteration... and the totally newbie question.
I earlier asked if this small amp is bridgeable to mono.
I earlier asked if this small amp is bridgeable to mono.
Not at all RadioSmuck. I plan to redo my first build guide so people can make an improved version of the Chinese one. Sadly the worst of it is the second rate chips are tough to desolder, so it'll remain a little bit lower wattage.
The $200 kit is for those that want something with the sound of an amp that costs $2-7k depending on power requirements. It handles well for it's power though as it doesn't cave to reactive loads like many amps.
The $200 kit is for those that want something with the sound of an amp that costs $2-7k depending on power requirements. It handles well for it's power though as it doesn't cave to reactive loads like many amps.