TDA7297 and Karlsonator

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I wasn't sure where to post this and hope I haven't broken any rules regarding posting in 2 forums.

I've built a new stereo comprising a TDA7297 amp and a 12AU7 Valve Cmoy Headphone for preamp. The speakers are a pair of foam core Karlsonators with TB W3-881SJF drivers.
It is really quite remarkable how remarkable this little little set-up sounds.
It was great fun to build- hope you enjoy it :D

cheers
 

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I wasn't sure where to post this and hope I haven't broken any rules regarding posting in 2 forums.

I've built a new stereo comprising a TDA7297 amp and a 12AU7 Valve Cmoy Headphone for preamp. The speakers are a pair of foam core Karlsonators with TB W3-881SJF drivers.
It is really quite remarkable how remarkable this little little set-up sounds.
It was great fun to build- hope you enjoy it :D

cheers


Fun. Very creative build.
 
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Joined 2012
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Lunch money amp rocks!

Prezden,
My TDA7297's just arrived from China. $5.36 ea shipping included! It really is a lunch money amp (http://www.diyaudio.com/forums/chip-amps/231988-what-heck-its-less-than-lunch.html) but last a lot longer than 1-meal. I hooked them up to my 0.4x Karlsonators (http://www.diyaudio.com/forums/full-range/239338-mini-karlsonator-0-53x-dual-tc9fds.html) and a 19 volt laptop brick and using my phone as the source. The amp sounds great! Very nice detailed sound, great bass, overall very neutral. I am used to class D amps though and almost burned myself when I picked it up by the heatsink after blasting at high volumes.
A fantastic deal anyway you look at it. The heatsink, 50k dual pot, or terminals would all cost about $5 ea to buy from one of the electronic parts suppliers in the US.

Wondering where they will live now... maybe as a powered mini Karlsonator mp3 player?
 

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I just tried the lunch amp with the 0.53x scale Karlsonators with the dual Vifa TC9FD drivers (91dB efficient), wow! It sounds amazing. There is a certain visceral depth and presence that just grabs and engages you and you want to hear more. This is a bone stock amp and I think improvements are readily available with input caps swapped to poly foil, Panasonic FC power cap, and removal of pot. But even in stock form, I really like the sound.
 
I just tried the lunch amp with the 0.53x scale Karlsonators with the dual Vifa TC9FD drivers (91dB efficient), wow! It sounds amazing. There is a certain visceral depth and presence that just grabs and engages you and you want to hear more. This is a bone stock amp and I think improvements are readily available with input caps swapped to poly foil, Panasonic FC power cap, and removal of pot. But even in stock form, I really like the sound.

Hi there X. How would you say the sound compares to the TPA3116?
 
Hi X
Here's a few photos of the stupa amp. As you can see the inside of the bottom compartment is a bit of a wiring knight mare :eek:
I'm thinking of building another one with the 3116 and see how they would compare. So far I refer the sound of the 3116 but they are both pretty incredible.
 

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Hi there X. How would you say the sound compares to the TPA3116?

I have not had a chance to do an A/B test with same speakers and same source yet. But initial impression is that it is very nice but you can hear more distortion at higher volumes. The TDA can get about 20 watts at 1% THD with 19 volt PS whereas the TPA3116 can get 40 watts at 0.1% THD. So they are in different class altogether if you push them hard. However, if you play them both at moderate 8 watts/channel they sound quite similar with the TPA appearing to have better bass, clearer highs, and more clarity in general. But at $5, it is an amazing sound that is I would say about 80% of the TPA.
 
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Hi X
Here's a few photos of the stupa amp. As you can see the inside of the bottom compartment is a bit of a wiring knight mare :eek:
I'm thinking of building another one with the 3116 and see how they would compare. So far I refer the sound of the 3116 but they are both pretty incredible.

Nice look there Prezden - like a temple in shape. :D
Does it get too hot under the box with the TDA heat sink?
 
Actually there is something that beats the TPA3116. The Shiznit prototype by Gary Marsh (see the custom-made Boominator amplifier thread for details) with TPA3118 running 1SPW modulation and variable voltage dc-dc controller gets an "idle" consumption of about 14mA including the dc-dc converter, DSP chip, µcontroller, and everything else running. I'm using the term "idle" loosely here as it turns on and off automatically with signal input so the actual idle is 470µA (sensing circuits are on). The 14mA is just in the about 2 minute window from signal detection says no signal until it actually shuts down.
 
But I'm not strictly high efficiency because of solar charging and for environmental reasons but because energy efficiency is the only way our civilization can have a future. Using 4-5 (or in the case off class A amp 100) times more energy than is needed is a wasteful practice that should be eliminated where ever possible. And what better way to start than by the things you use in your own home.
 
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