it´s ok thanks...i just sort my self to plan the next step for modding the FX502s. so i go through the LM317 topic and i found your advice.
chris
There is a very unexciting online shop for TI parts, called the TIstore. Every other week they offer free shipping and other discounts and most Ebay sellers have higher sellingprices, because everybody knows cheap offers are fake 🙂
TIstore is boring.
TIstore is boring.
Attachments
TI store (free shipping at the moment, no discount code entered)
Order Summary
Edit >
LME49720NA/NOPB (2)
$5.36
Subtotal:
$5.36
Shipping & Handling:
$0.00
Total (USD):
$5.36
Ebay link from few posts back:
GENUINE LME49720NA Texas Instruments Dual OpAmp Audiophile; TI LME49720 DIP-8
Condition:
New
Item price:
$3.45
Quantity:
$6.90
Shipping cost
+ $6.25
Subtotal (2 items):
$6.90
Shipping to XXXX:
$6.25
Total:
$13.15
Problem is, TI doesn't tell you the LME is genuine, mmm, very difficult to make the boring choice 😀
Order Summary
Edit >
LME49720NA/NOPB (2)
$5.36
Subtotal:
$5.36
Shipping & Handling:
$0.00
Total (USD):
$5.36
Ebay link from few posts back:
GENUINE LME49720NA Texas Instruments Dual OpAmp Audiophile; TI LME49720 DIP-8
Condition:
New
Item price:
$3.45
Quantity:
$6.90
Shipping cost
+ $6.25
Subtotal (2 items):
$6.90
Shipping to XXXX:
$6.25
Total:
$13.15
Problem is, TI doesn't tell you the LME is genuine, mmm, very difficult to make the boring choice 😀
Hi Chermann
In your LM317 picture, it is printed "only sell in Japan" below the inductors.
My V3 blue board FX502S is no this label.
May be V5 for Japan only without any change on layout but I am not sure.
In your LM317 picture, it is printed "only sell in Japan" below the inductors.
My V3 blue board FX502S is no this label.
May be V5 for Japan only without any change on layout but I am not sure.
I ordered two LME49720NA from here
GENUINE LME49720NA Texas Instruments Dual OpAmp Audiophile; TI LME49720 DIP-8 | eBay
What are my chances for genuine vs. fake?
GENUINE LME49720NA Texas Instruments Dual OpAmp Audiophile; TI LME49720 DIP-8 | eBay
What are my chances for genuine vs. fake?
Received today 502spro. First impression: sound really very good, definitely better than Breeze audio double tpa3116.
But after install LME49720NA sound became even much better, amazing!
One thing - it very hot even at low sound volume. Very small heatsink. I guess it's need make holes and install bigger heatsink.
Two big capacitors too closely with heatsink and also hot. So replace of heatsink required, or there will be a big boom one day.
rev.3
But after install LME49720NA sound became even much better, amazing!
One thing - it very hot even at low sound volume. Very small heatsink. I guess it's need make holes and install bigger heatsink.
Two big capacitors too closely with heatsink and also hot. So replace of heatsink required, or there will be a big boom one day.
rev.3
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Do you have a link to the opamp at shop.ti.com? I can't find it searching for LME49720NA?
Is this what you are referring to in the TI Store?
LME49720NA/NOPB | Texas Instruments | TI Store
But that is the can-style, not the socket-style, isn't it? I'm confused.
Hi noasds
actually the BB2134 is "burn in" (with the psu from amp 1) and on the weekend i will give you a sound impression.
can you make some pics from your amp to compare the photos....? maybe then its clearer.......or not 😀
chris
I have to check my temperatur situation but in generally the efficiency at low power out is less than 70-80% , e.g. BTL ...look at about 1W ouput @ 25°C ambient Temperature !
page 10, chapter 7.9 Ti datasheet TPA3250
chris
Attachments
here is the overview of different housings
1 PDIP is the good old housing - as you have it in the FX502S
2 SOIC is for SMD
3 To99 is the metall round housing - if you want to try this check the internet for a DIP adapter = DIP 8 socket, as you have it in the FX502
chris
1 PDIP is the good old housing - as you have it in the FX502S
2 SOIC is for SMD
3 To99 is the metall round housing - if you want to try this check the internet for a DIP adapter = DIP 8 socket, as you have it in the FX502
chris
Attachments
The board:
It's worth replacing NE5532 with LME49720 for better sound
Capacitors too close with heatsink, no room between. Who is that ingenious developer who decided to dissipate heat to the capacitors? It is because they are aluminum... maybe he thought
When the cover is open, the board is not very hot sure, but when the casing is closed I think the amplifier will not last long.
It's worth replacing NE5532 with LME49720 for better sound
Capacitors too close with heatsink, no room between. Who is that ingenious developer who decided to dissipate heat to the capacitors? It is because they are aluminum... maybe he thought
When the cover is open, the board is not very hot sure, but when the casing is closed I think the amplifier will not last long.
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PCB is heatsink for tpa3250, the purple thing is basicly there because you want to see heatsink, it could also affect performance in a bad way, I think doctormord spent some time changing heatsink on 3251/55 to reduce negative impact.
That doesn't mean you will hear an improvement, because worse performance is what some will prefer, for the (purple) heatsink, for high speed dip opamps, for the aircore inductors, for many things.
That doesn't mean you will hear an improvement, because worse performance is what some will prefer, for the (purple) heatsink, for high speed dip opamps, for the aircore inductors, for many things.
hi noasds
can you check the temp with a temparature measurment tool?
1 check if you have thermal paste under the heatsink
2 mount a bigger heatsink= more fans = more surface for cooling
3 contact the heatsink with a diy construction 😀
to the alu case - avoid electrical contact to the TPA3250 !
4 drill holes on the top and buttom case where the chip is mounted on the pcb = to get better air flow
if i did a long sound ssession with my not mod amp1 a check the cass on the top it was slightly more the hand warm. so i have to investigate on the weekend to check the temperature at my amps.
can you check the temp with a temparature measurment tool?
1 check if you have thermal paste under the heatsink
2 mount a bigger heatsink= more fans = more surface for cooling
3 contact the heatsink with a diy construction 😀
to the alu case - avoid electrical contact to the TPA3250 !
4 drill holes on the top and buttom case where the chip is mounted on the pcb = to get better air flow
if i did a long sound ssession with my not mod amp1 a check the cass on the top it was slightly more the hand warm. so i have to investigate on the weekend to check the temperature at my amps.
any link?
do you mean "vibration" or the thermal dissapation with a better K/W heatsink?