OK, so, that needs to be taken care of. Maybe there should be no issue with the amp being opened on power off I guess?
The 7498 has a big ceramic resistor on the output, I thought it wouldn't have a thump problem.
IIRC, the wiener does not have the thump issue.
The 7492 is very attractive due to the price for two being equal to that of one Weiner or 7498.
The 7498 has a big ceramic resistor on the output, I thought it wouldn't have a thump problem.
IIRC, the wiener does not have the thump issue.
The 7492 is very attractive due to the price for two being equal to that of one Weiner or 7498.
Hi
I bought the same TDA 7492 and found the amp also i little bit harsh on the top end . replaced the elco with Panasonic FM , put extra philips elco (blue on the picture ) and replaced input caps with wima 1 mf MKP 10.
I have 8 ohm speakers so i also replaced the inductors with 33uH/3 A toroid,s (cheap on ebay ) ( this is the standard value acoording to manufacture specs ) . Harshness is gone and it is now one of my better sounding D amps . so no need for a snubber .
Jeremy
I bought the same TDA 7492 and found the amp also i little bit harsh on the top end . replaced the elco with Panasonic FM , put extra philips elco (blue on the picture ) and replaced input caps with wima 1 mf MKP 10.
I have 8 ohm speakers so i also replaced the inductors with 33uH/3 A toroid,s (cheap on ebay ) ( this is the standard value acoording to manufacture specs ) . Harshness is gone and it is now one of my better sounding D amps . so no need for a snubber .
Jeremy
Attachments
Delivery Source for TDA7492 - Overview wanted
At most suppliers like Mouser I read "not available" for this monolithic integrated circuit in class-D - go to
TDA7492 STMicroelectronics | Mouser
Are there other suppliers, where this type is in stock?
Or is this IC already obsolete ?
I need small quantities for replace at ST evaluation boards in faulty condition.
Thank you for advices.
At most suppliers like Mouser I read "not available" for this monolithic integrated circuit in class-D - go to
TDA7492 STMicroelectronics | Mouser
Are there other suppliers, where this type is in stock?
Or is this IC already obsolete ?
I need small quantities for replace at ST evaluation boards in faulty condition.
Thank you for advices.
Search for it under " TDA749213TR "
This is just a tape and reel part number ( http://www.mouser.com/ds/2/389/CD00205863-252534.pdf )
I finally got around to doing some of the mods x did in the beginning of this thread. I spent a few hours listening to the amp stock yesterday, then popped in the Panasonic OSCON 330uF 25V SEPF caps and a Panasonic 560uF 35V FM cap. Hooked it back up and listened for a bit longer.
Gear:
Onkyo C-7030 cd player
First Watt B1 clone
tda7492 amp
Fostex FE126En's in BK12 cabinets
In stock form I thought the tda7492 was not that great, the hf was harsh, and a bit distorted sounding. The lf seemed a little thin, and slow'ish maybe.
Post mods, the hf is improved some, though still not quite there for me. The low end is much improved, much more full and authoritative.
I haven't done the snubber mod, as I don't think I have what's needed on hand.
Looking for suggestions as to what to try next, if it's the snubber mod, I'll get the parts and give it a whirl.
I'm also going to put it into a real case at some point, with some decent rca's and binding posts.
Thanks!
Gear:
Onkyo C-7030 cd player
First Watt B1 clone
tda7492 amp
Fostex FE126En's in BK12 cabinets
In stock form I thought the tda7492 was not that great, the hf was harsh, and a bit distorted sounding. The lf seemed a little thin, and slow'ish maybe.
Post mods, the hf is improved some, though still not quite there for me. The low end is much improved, much more full and authoritative.
I haven't done the snubber mod, as I don't think I have what's needed on hand.
Looking for suggestions as to what to try next, if it's the snubber mod, I'll get the parts and give it a whirl.
I'm also going to put it into a real case at some point, with some decent rca's and binding posts.
Thanks!
Pcgab, thanks for trying my mods! I looked at the photo and remarked it looks just like my amp 
I have moved on to the 7498 which has much better bass stock form. I don't change anything on the TDA7498 (blue board with black heat sink and pot). That board had mislabeled outputs but get past that and it's good.
The bootstrap snubber is needed on this amp to get the harshness down. 330pF and 10ohm resistor.
I have moved on to the 7498 which has much better bass stock form. I don't change anything on the TDA7498 (blue board with black heat sink and pot). That board had mislabeled outputs but get past that and it's good.
The bootstrap snubber is needed on this amp to get the harshness down. 330pF and 10ohm resistor.
A few weeks ago I purchased a tda7492p bluetooth amp and superglued it to the side of one of a pair of RS Minimus 7 speakers with the intention of giving the setup to my granddaughter to use with her tablet. I think she will be pleased, if I get around to giving it to her!,
Over the last couple of years I have purchased several d-amps and boards, a Lepai 2020 amp, an SMSL SA-S1 (2020?), also a 3116 board and a 3116 2.1 board. All the purchases in this paragraph absolutely kill FM reception, even a portable from many feet away.
There are a couple of good fm stations here that I did not want to give up so I moved on to AB chip amps which do not produce the interference.
Yesterday, I removed one of the 7's and connected a big old Leak 2060 to which I had just replaced a tweeter cap.
Anyway during listening, I thought I would pass an fm tuner by the amp and to my amazement, no interference at all, even with the tuner just inches from the tda7292p.
I have ordered another 7292 bluetooth amp to try, in place of the 7297 I have been using for the last 3 years.
Over the last couple of years I have purchased several d-amps and boards, a Lepai 2020 amp, an SMSL SA-S1 (2020?), also a 3116 board and a 3116 2.1 board. All the purchases in this paragraph absolutely kill FM reception, even a portable from many feet away.
There are a couple of good fm stations here that I did not want to give up so I moved on to AB chip amps which do not produce the interference.
Yesterday, I removed one of the 7's and connected a big old Leak 2060 to which I had just replaced a tweeter cap.
Anyway during listening, I thought I would pass an fm tuner by the amp and to my amazement, no interference at all, even with the tuner just inches from the tda7292p.
I have ordered another 7292 bluetooth amp to try, in place of the 7297 I have been using for the last 3 years.
Thanks, it was the speakers.
It seems my old efficient 15 OHM Tannoys do not like D-amps.
For the last 3 years they have been connected to a 7297 board which allows me to receive fm.
Yesterday I replaced the 7297 with a d-amp and and the problem with fm was back. I can remember putting clamp on ferrites on every cable and moving the antenna around, but no luck. I had even connected a rf line filter.The same d-amp works perfectly with other speakers and fm.
It seems my old efficient 15 OHM Tannoys do not like D-amps.
For the last 3 years they have been connected to a 7297 board which allows me to receive fm.
Yesterday I replaced the 7297 with a d-amp and and the problem with fm was back. I can remember putting clamp on ferrites on every cable and moving the antenna around, but no luck. I had even connected a rf line filter.The same d-amp works perfectly with other speakers and fm.
Hi to all
I want to do the snubber mod on TDA 7492 on blue bord. Can I use a styroflex cap instead of a ceramic cap (330 pf ) . ( I have some styroflex but no ceramic caps )
I already changed the inductors (33uH for 8 ohm speakers ) and changed the input cap to wima mkp 10 bypassed with 0,33 MKT (to soften the highs ) and changed the
elco for 2200 fm Panasonic .
I want to do the snubber mod on TDA 7492 on blue bord. Can I use a styroflex cap instead of a ceramic cap (330 pf ) . ( I have some styroflex but no ceramic caps )
I already changed the inductors (33uH for 8 ohm speakers ) and changed the input cap to wima mkp 10 bypassed with 0,33 MKT (to soften the highs ) and changed the
elco for 2200 fm Panasonic .
Sure, the polystyrene caps can work as snubber caps as long as voltage rating is sufficient.
Look at Figure 28: break the traces for pins 30 & 31 (open) to get lowest gain setting of 21.6dB, leave 31 connected to Vdd (3.3v) and break pin 30 to get 27.6dB, leave pin 30 connected to Vdd and break pin 31 t0 get 31.1dB gain. Both connected is 33.6dB.
http://www2.st.com/content/ccc/reso...df/jcr:content/translations/en.CD00205863.pdf
Look at Figure 28: break the traces for pins 30 & 31 (open) to get lowest gain setting of 21.6dB, leave 31 connected to Vdd (3.3v) and break pin 30 to get 27.6dB, leave pin 30 connected to Vdd and break pin 31 t0 get 31.1dB gain. Both connected is 33.6dB.
http://www2.st.com/content/ccc/reso...df/jcr:content/translations/en.CD00205863.pdf
Thanks for your reply,
A took the pin description as point of reference and counted 6 en 7 places down to gain 1 (31 ) and gain 0 (30) and then followed the traces to cut as far as possible from the chip .(I already spoiled another one)
On the Feixiang td 7492 blue board I could cut traces near R8 ((gain 1) and R28 (gain 0 ) but only with the help of a stereo microscope
Best setting so far 31db gain . (restored connection pin 30 and left 31 open )
A took the pin description as point of reference and counted 6 en 7 places down to gain 1 (31 ) and gain 0 (30) and then followed the traces to cut as far as possible from the chip .(I already spoiled another one)
On the Feixiang td 7492 blue board I could cut traces near R8 ((gain 1) and R28 (gain 0 ) but only with the help of a stereo microscope
Best setting so far 31db gain . (restored connection pin 30 and left 31 open )
SMSL SA-50 Schematic wanted
I want to reduce the gain factor to the lowest possible value at this T-amp (TDA7492 inside):
SMSL SA-50 T-AMP SA50 2 x 50 W SCHWARZ Digitalverstärker Class D Verstä | eBay
Therefore I want to have the genuine schematic.
Unfortunately until now I get no reply of an inquiry to
SMSL-AUDIO@qq.com
the address is follow:
8th Floor
B6A Building JunFeng industrial zone
Fuyong
BaoAn district
Shenzhen
China
Maybe a member of China can ask for me there.
Thank you for your efforts.
I want to reduce the gain factor to the lowest possible value at this T-amp (TDA7492 inside):
SMSL SA-50 T-AMP SA50 2 x 50 W SCHWARZ Digitalverstärker Class D Verstä | eBay
Therefore I want to have the genuine schematic.
Unfortunately until now I get no reply of an inquiry to
SMSL-AUDIO@qq.com
the address is follow:
8th Floor
B6A Building JunFeng industrial zone
Fuyong
BaoAn district
Shenzhen
China
Maybe a member of China can ask for me there.
Thank you for your efforts.
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Have you looked at the data sheet to see what pin needs "adjusting" and how?
Attachments
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