If speaker is disconnected, it looks like AC voltage gain becomes 56k/.22 (assuming amp can provide this), is this problematic?
Hello, because of availability I bought two STK4241 Mk5 just to begin with a current drive amplifier.
One question, is the MK5 Version for a conversion to current drive functional, too? (The other one was the MKII Version optimized for current drive).
As far as I can see there are only minor differences in the schematic. Basically its all the same.
One question, is the MK5 Version for a conversion to current drive functional, too? (The other one was the MKII Version optimized for current drive).
As far as I can see there are only minor differences in the schematic. Basically its all the same.
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Existing amplifier with STK4152_II is Technics SU-Z250 amplifier. In germany easily to be found as used item. And not expensive. Usually for 30 to 50 Euros.
I own two of them. Would be nice to see how to transform it to a current driven amplifier as you do not need to build an amplifier from the scratch.
https://www.radiomuseum.org/r/technics_su_z250.html
https://pdf1.alldatasheet.com/datasheet-pdf/download/41592/SANYO/STK4152.html
I own two of them. Would be nice to see how to transform it to a current driven amplifier as you do not need to build an amplifier from the scratch.
https://www.radiomuseum.org/r/technics_su_z250.html
https://pdf1.alldatasheet.com/datasheet-pdf/download/41592/SANYO/STK4152.html
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Hello, I found this statement on TDA2003 chipamp which is claimed to be current drive without modification, can that be true?
#2
ivanlukic
Member
2013-05-17 5:43 pm#2
It is my favourite chip amp. Great sound is due to current feedback topology which is rare in chip amps. It is designed for car radio and for battery supply. If you use it with 8 ohm speakers it will deliver only about 5W and will clip badly if you push it hard. If you like it's sound as much as I do, I suggest you to try TDA2005 which is the same amp but in bridge mode. You won't need output cap for it. It offers twice as much power as TDA2003. But in any case you should use some kind of regulated supply and avoid supplies of over 12V.
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It is an amplifier chip that does not work in bridge tied load mode and that has an external feedback network, so it should be possible. The single supply and peculiar way of biasing complicate things somewhat.
"Current drive" is not same-as "current feedback". (I could debate if 2 Ohms is really "CFB" here but why?)
Try this:
Never saw any oscilasions without that 220 ohm resistor on lm3875 , lm3886 chips. They just raise voltage to maximum if nothing connected. No surprises when pluging speaker.just faint click. Why are you expecting surprise? There is no technical reason for surprise to accur i think.
I will start to try out the TDA2003 in current drive. I have nice Pioneer 13cm fullrange driver in a marvelous old enclosure from the 70ies.
This driver needs added hi and lows to work properly.
If current feedback works it will make the frequencies without assisted EQ.
I have measurement equipment and will measure the result.
As a preamp functions a Bluetooth module for 3 euros. I will look for a 9 Volt dc source for it as it has a LM7805 regulator.
I will ad some small Cs between its legs like mentioned in the data sheet. I do not see them on the pcb.
As DC source for the TDA2003 I have 15 Volt SMPS.
This driver needs added hi and lows to work properly.
If current feedback works it will make the frequencies without assisted EQ.
I have measurement equipment and will measure the result.
As a preamp functions a Bluetooth module for 3 euros. I will look for a 9 Volt dc source for it as it has a LM7805 regulator.
I will ad some small Cs between its legs like mentioned in the data sheet. I do not see them on the pcb.
As DC source for the TDA2003 I have 15 Volt SMPS.
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Does anyone know something about these Bestonesound speakers? Never found something on them on the web.
