Thanks,
I have no trouble with a pair of multiband receivers with whip antenna connected to the 7297. I get crystal clear fm stereo from both, which is not the case when connected to the 5 cheap d-amps I have purchased over the last 18 months.
On Ebay the little fm module is only about $9 incl. shipping and I have ordered one
I have no trouble with a pair of multiband receivers with whip antenna connected to the 7297. I get crystal clear fm stereo from both, which is not the case when connected to the 5 cheap d-amps I have purchased over the last 18 months.
On Ebay the little fm module is only about $9 incl. shipping and I have ordered one
I have my 7297 powered by an inexpensive LM338 board and a transformer ripped from an old amp. Runs cool @ 18vdc and sounds so sweet.Yes, that little FM module is stereo. Reception is OK with a metre length of wire but I'm in a fairly high signal strength area. It has memory presets too
I still can't quite believe how good that 7297 sounds!
Cheers
Just received my little FM tuner module this morning and have a question regarding the L/R input. What would this be used for?
Thanks
It's an AUX input, Line in. Very handy. I've got a CD player plug in to it. Unfortunately the module didn't come with the 3-pin plug and sourcing them seems difficult so I ended up doing a botch job by soldering directly to the tiny pins.
On the remote, the MODE button selects FM, USB or AUX In.
Cheers
On the remote, the MODE button selects FM, USB or AUX In.
Cheers
Thanks, mine came without without a 3 pin plug also. The tuner is very sensitive, I was picking up strong stations without an antenna. Just 12 inches of wire pulls in all the stations I listen to.It's an AUX input, Line in. Very handy. I've got a CD player plug in to it. Unfortunately the module didn't come with the 3-pin plug and sourcing them seems difficult so I ended up doing a botch job by soldering directly to the tiny pins.
On the remote, the MODE button selects FM, USB or AUX In.
Cheers
The LM338 I purchased has a 12v fan which is not needed when powering the 7297, so the output is now connected to the tuner module, perfect.
How's the weather where you are? Down South, according to my old mum, everything is flying around.
How's the weather where you are? Down South, according to my old mum, everything is flying around.
Thankfully it missed us up here in the North Midlands. It's now moved into Europe with winds recorded at 109 mph in Germany
On radiosmuck's recommendation, I purchased one of these amps, and I have to say I am very impressed by this $5 amp. It does outperform my SMSL SA-S1 TA2020 T-amp. Here is how I have it connected for now in my makeshift chassis. I took the cheap-looking 2,200uF/25V electrolytic power supply cap out and replaced it with a new Panasonic FM electrolytic cap of the same value. It tightened up the bass and improved the slam. I'm considering some more improvements like replacing the cheap Polyester film caps with some better Polypropylene caps, and replacing the volume pot with a low cost SMD resistor-based stepped attenuator. Can anyone recommend any other improvements?
You are the only member that have found the need to change anything on these little amps
Danielwritesback, who seems a very experienced tweaker suggested doing nothing other than perhaps a linear PS.
I purchased a cheap LM338 3-36v power supply, set now to 18v, added a touch of super glue to the shaft to lock and it sounds great.
I could not resist purchasing a 16 volt Lithium-ion drill battery pack in the Sears batgain bin over the weekend. Only 1200mah but it kept the amp and an fm tuner module going for 13.5 hours!
Danielwritesback, who seems a very experienced tweaker suggested doing nothing other than perhaps a linear PS.
I purchased a cheap LM338 3-36v power supply, set now to 18v, added a touch of super glue to the shaft to lock and it sounds great.
I could not resist purchasing a 16 volt Lithium-ion drill battery pack in the Sears batgain bin over the weekend. Only 1200mah but it kept the amp and an fm tuner module going for 13.5 hours!
With the amp I bought, jazz sounds great, but with classical and some rock music, I could really sense an unnatural glare in the upper midrange and treble that really detracts from the rest of the amp's goodness. Even with simpler string quartets, this slight glare would become bothersome. Letting the amp burn in some more with playing time helped, but it didn't entirely eliminate the problem. Earlier today, I took those cheap Polyester film caps out and replaced them with larger Panasonic ECQP .22uF/400V Propylene film and foil caps that have tinned Copper leads. These caps look awkward on this tiny amp module, but the sound is so improved. I can really listen to Holst's "The Planets" and enjoy the crescendos.
Call me an audiofool, but my ears tell me that certain component replacements can pay big dividends, especially with such a simple circuit. The amp sounds much cleaner in the upper registers.
Thanks for telling me about this chip amp. I wonder why more people haven't been turned on to this little budget wonder.
Call me an audiofool, but my ears tell me that certain component replacements can pay big dividends, especially with such a simple circuit. The amp sounds much cleaner in the upper registers.
Thanks for telling me about this chip amp. I wonder why more people haven't been turned on to this little budget wonder.
While this little board sounds pretty good as is, why not upgrade the few parts there are? It's super easy and for a little investment, this amp can actually sound quite a bit better.
I've made seven amps using this same board and five of them I've upgraded. I highly recommend changing the volume pot, the main capacitor, the input coupling caps and using good hardware, good wire and good solder and getting the most out of this cool little chip.
Here's one I made recently for someone and it sounds considerably better than the stock board.
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I'm not really interested in guilding the Lilly, I was hoping that this little amp would not go the way of the Lepai where changes were being made before the original was ever auditioned.
I'm very happy with the amp 'as is' and have no problem with the volume control. I just happen to believe the magic is in the chip and how could TI get it wrong, there is nothing on the board. I'm also a believer in the placebo effect
I'm very happy with the amp 'as is' and have no problem with the volume control. I just happen to believe the magic is in the chip and how could TI get it wrong, there is nothing on the board. I'm also a believer in the placebo effect
If you are happy with listening to FM with this $5.00 board in its "as is" form, why would you possibly care what others are doing to maximize the performance of this chip?
The human brain is easily deceived, take for example simple optical illusions.
None of the "performance enhancements" on the D-amp threads have ever been verified technically, it has always been HEARsay. In actual fact, d-amps were worse with regard to rf interference after "modding", which was never discussed.
There happens to be a couple of fm stations I enjoy besides cd and iinternet radio and I see no reason to give up on them. Fortunately the little $5, non switching, amplifier does not degrade fm.
None of the "performance enhancements" on the D-amp threads have ever been verified technically, it has always been HEARsay. In actual fact, d-amps were worse with regard to rf interference after "modding", which was never discussed.
There happens to be a couple of fm stations I enjoy besides cd and iinternet radio and I see no reason to give up on them. Fortunately the little $5, non switching, amplifier does not degrade fm.
I am considering the LM-338 voltage regulator module from eBay seller audiowind-2010, the same regulator that activexp is using with his TDA7297. For now, the amp sounds great with my modified Power One MAP110-S148 SMPS.
Replacing the stock Polyester caps with the Panasonic ECQP Propylene film and foil caps was a significant improvement for female vocals like Montserrat Figueras and Anonymous Four. With the stock caps, some vocals were strident. Strings in orchestral music were smeared with some graininess. I played Pink Floyd's "Dark Side of the Moon" on SACD, and the amp played loud, complex passages in "Time" and "The Great Gig in the Sky" without the glare and graininess of the stock caps.
I connected my Audio Research PH5 phono stage directly to the TDA7297 and was treated to some great performances in my man cave. The holographic soundstage that I get from the phono stage really comes through nicely with the little amp. Does it beat the combination of my Audio Research LS7 line stage preamp and restored, EFB-modified Dynakit Stere35? No, but for a tiny fraction of what I've invested in my tube amps, it is quite respectable.
Replacing the stock Polyester caps with the Panasonic ECQP Propylene film and foil caps was a significant improvement for female vocals like Montserrat Figueras and Anonymous Four. With the stock caps, some vocals were strident. Strings in orchestral music were smeared with some graininess. I played Pink Floyd's "Dark Side of the Moon" on SACD, and the amp played loud, complex passages in "Time" and "The Great Gig in the Sky" without the glare and graininess of the stock caps.
I connected my Audio Research PH5 phono stage directly to the TDA7297 and was treated to some great performances in my man cave. The holographic soundstage that I get from the phono stage really comes through nicely with the little amp. Does it beat the combination of my Audio Research LS7 line stage preamp and restored, EFB-modified Dynakit Stere35? No, but for a tiny fraction of what I've invested in my tube amps, it is quite respectable.
Little Black Box with TDA7297
I just packed my Little Black Box (LBB) with a TDA7297 board, and added a YINCON 6800uf 50v capacitor. I am simply amazed by the performance of this LBB, its dead silent and without any switching, or ground loop hum in the subs i get from some of the class D amps i have tried in my set up (two flanking Sony active subs and two Voigt pipes) .
It sounds a little warmer than the D amps with softer and more detailed bass. I am quite happy with it but have only listened to the LBB a couple hours so it hard to tell for sure but its definitely one of the better amps i have tried.
I have a Miniwatt n3 with two Psvane el84 and one Full Music 12ax7 tube as a reference amp. The Little Black Box is right up there close to the Miniwatt. The Miniwatt may have a little bigger stage separation but the LBB sound quality is definitely close to the Miniwatt.
Thanks again to the forum for the inspiration and help, i just started this hobby a couple of years ago and i am getting more and more addicted
goo
Here is some Pics:
Little Black Box with TDA7297 | Flickr - Photo Sharing!
I just packed my Little Black Box (LBB) with a TDA7297 board, and added a YINCON 6800uf 50v capacitor. I am simply amazed by the performance of this LBB, its dead silent and without any switching, or ground loop hum in the subs i get from some of the class D amps i have tried in my set up (two flanking Sony active subs and two Voigt pipes) .
It sounds a little warmer than the D amps with softer and more detailed bass. I am quite happy with it but have only listened to the LBB a couple hours so it hard to tell for sure but its definitely one of the better amps i have tried.
I have a Miniwatt n3 with two Psvane el84 and one Full Music 12ax7 tube as a reference amp. The Little Black Box is right up there close to the Miniwatt. The Miniwatt may have a little bigger stage separation but the LBB sound quality is definitely close to the Miniwatt.
Thanks again to the forum for the inspiration and help, i just started this hobby a couple of years ago and i am getting more and more addicted
goo
Here is some Pics:
Little Black Box with TDA7297 | Flickr - Photo Sharing!
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Rich,
I drive the amp from a 12v SLA, and it seems like the increased capacity made it play louder, with a fuller bass and over all better sound. I did not listen so carefully before i changed it but its definitely better.
I was thinking of maybe trying some new caps like you did, but it sounds pretty good as it is now. However what is the value of your Panasonic caps?
The small orange plastic stock caps on my board says 0.22 K 63, is that 0.22uF 63V? I noticed the Data sheet recommend 0.22uF.
Thanks
goo
I drive the amp from a 12v SLA, and it seems like the increased capacity made it play louder, with a fuller bass and over all better sound. I did not listen so carefully before i changed it but its definitely better.
I was thinking of maybe trying some new caps like you did, but it sounds pretty good as it is now. However what is the value of your Panasonic caps?
The small orange plastic stock caps on my board says 0.22 K 63, is that 0.22uF 63V? I noticed the Data sheet recommend 0.22uF.
Thanks
goo
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I used a pair of 0.22uF/400V Panasonic ECQP Polypropylene film and foil caps I bought from Jim McShane in the US. The ECQP series is a discontinued product line of caps from Panasonic. Many use the Vishay Sprague 716P "Orange Drop" Polypropylene film and foil caps that are similar, and still available.
But, but ... where's the DIY in that?
UpgaradedTDA7297 with Silmic II coupling caps, Pan FC ps cap, schottky diode and pin headers.
Others have film coupling caps, Pan FM and old HFQ ps caps and cheap stepped attens. for volume.
When they're this cheap I always get a couple and keep one stock ...
PS putting a good COG or NPO ceramic right on the PS pins (both sides) with a big FM is my next step ...
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What value of Elna Silmic II caps are you using? I had read elsewhere on these forums that someone using >1uF caps had problems with their TDA7297 amp oscillating, but perhaps the root cause might have been something else.
I'm also interested in the purpose of the Schottky diode. It looks like it's wired across the DC voltage.