progress?
If so I can see the btl that you returned was yuanjing. I have a cheap single ta2022 stereo board from yuanjing and it hums too (on both channels with inputs shorted). I listen to the ljm v1.2 stereo version exactly the same as yours, with a resistor between inductor and 5V stabilizer (the schematics show a diode at that position). No hum at all and very clean sound. (I did add extra heatsinks on the two stabilizers without heatsink).
So please tell us how your second btl board is doing?
Greetings
I suppose you are also on maydaydiy.wordpress.com?
If so I can see the btl that you returned was yuanjing. I have a cheap single ta2022 stereo board from yuanjing and it hums too (on both channels with inputs shorted). I listen to the ljm v1.2 stereo version exactly the same as yours, with a resistor between inductor and 5V stabilizer (the schematics show a diode at that position). No hum at all and very clean sound. (I did add extra heatsinks on the two stabilizers without heatsink).
So please tell us how your second btl board is doing?
Greetings
Yes, that is me.
I haven't updated it in ages though.
I haven't powered it up yet as I'm waiting for the xlr connectors.
Sorry about the short reply, writing from my phone.
I haven't updated it in ages though.
I haven't powered it up yet as I'm waiting for the xlr connectors.
Sorry about the short reply, writing from my phone.
I've done some work on the amp.
The boards are identical except color.
I've removed on board rectifier bridges to be able to power them with a 0-22vac 0-22vac 400VA toroidal transformer.
Added 10000uF per rail on the rectifying board.
Using ICEL 1% 2.2uF parallel with 1uF Vishay BC as input caps.
Due to the size of the enclosure, I can't get the boards further away from the transformer.
Now I'm waiting for XLR connectors and I need to read up on TA2022 offset adjustment before doing the trimming and eventually putting the boards in BTL mode.
The boards are identical except color.
I've removed on board rectifier bridges to be able to power them with a 0-22vac 0-22vac 400VA toroidal transformer.
Added 10000uF per rail on the rectifying board.
Using ICEL 1% 2.2uF parallel with 1uF Vishay BC as input caps.
Due to the size of the enclosure, I can't get the boards further away from the transformer.
Now I'm waiting for XLR connectors and I need to read up on TA2022 offset adjustment before doing the trimming and eventually putting the boards in BTL mode.
Attachments
I found a SST01 softstart PCB in one of my parts boxes yesterday.
Unfortunately the BOM and other documentation seems to have been misplaced in the years since I bought the PCB.
I did find the relays and 5W resistor in the same box, but nothing else regarding the SST01.
Sorry about the crap phone pic.
This should be a good addition to the TA2022 BTL amp, especially with the 400VA toroid and extra capacitance.
Unfortunately the BOM and other documentation seems to have been misplaced in the years since I bought the PCB.
I did find the relays and 5W resistor in the same box, but nothing else regarding the SST01.
Sorry about the crap phone pic.
This should be a good addition to the TA2022 BTL amp, especially with the 400VA toroid and extra capacitance.
Attachments
Didn't get much done today as I'm waiting for parts, but I did solder speaker wires to the connectors. I used 1.5mm2 multistrand Cu in PVC (I think that's the insulation "RK" cable).
I hope to get far enough to trim DC offset of the boards(individually, in stereo mode).
I found some info saying it was OK to power on the TA2022 without anything connected to inputs/outputs.
I have misplaced my 25W 8R dummy loads some time over the years unfortunatly.
I have some metal work to do as well, I need to shorten the bolt holding the 400VA toroid transformer as I plan on mounting the SST01 on top of the transformer due to limited space in the enclosure.
I need to cut a hole for the power switch on the front panel etc.
A question;
Will the TA2022 x2 in BTL benefit from additional input caps, some kind of filter or similar on the connectors(chassis connectors)
I've come to realize I don't need a balanced signal after all, feeling a but stupid not having noticed that until recently, but XLR connectors will make the interconnect to the DCX2496 easier to make with balanced connectors in both ends.
I found some info saying it was OK to power on the TA2022 without anything connected to inputs/outputs.
I have misplaced my 25W 8R dummy loads some time over the years unfortunatly.
I have some metal work to do as well, I need to shorten the bolt holding the 400VA toroid transformer as I plan on mounting the SST01 on top of the transformer due to limited space in the enclosure.
I need to cut a hole for the power switch on the front panel etc.
A question;
Will the TA2022 x2 in BTL benefit from additional input caps, some kind of filter or similar on the connectors(chassis connectors)
I've come to realize I don't need a balanced signal after all, feeling a but stupid not having noticed that until recently, but XLR connectors will make the interconnect to the DCX2496 easier to make with balanced connectors in both ends.
I'm just about ready to test the amp now.
I figured I need to trim DC offset as low as possible on each board individually before jumpering them for BTL.
The switch I had originally intended to use(in the pics) unfortunatly broke.
I've ordered another, 15A 250VAC, switch.
I have connected PS gnd to "star-gnd" that connects to IEC earth.
Since I don't have my big 8R resistors, what power rating would be ok to use as dummy loads? I figured I'd need something or the caps would take forever to drain.
I may rebuild the rectifier/cap bank board, I could probably fit two more Panasonic ha 10000uF caps if I point to point wire bridges and caps.
What fuse rating would be enough for offset trim? 800mA slow(should be ok up to about 180W total, 0,8A*230VAC)? The 400VA toroidal transformer shouldn't cause that much inrush current with the P-A SST-01 softstart module.
Sorry about the cellphone pics.
I figured I need to trim DC offset as low as possible on each board individually before jumpering them for BTL.
The switch I had originally intended to use(in the pics) unfortunatly broke.
I've ordered another, 15A 250VAC, switch.
I have connected PS gnd to "star-gnd" that connects to IEC earth.
Since I don't have my big 8R resistors, what power rating would be ok to use as dummy loads? I figured I'd need something or the caps would take forever to drain.
I may rebuild the rectifier/cap bank board, I could probably fit two more Panasonic ha 10000uF caps if I point to point wire bridges and caps.
What fuse rating would be enough for offset trim? 800mA slow(should be ok up to about 180W total, 0,8A*230VAC)? The 400VA toroidal transformer shouldn't cause that much inrush current with the P-A SST-01 softstart module.
Sorry about the cellphone pics.
Attachments
Didn't get around to trimming DC.
Did however increase the cap bank to 4x 10000uF Panasonic ha.
I had to mount the whole thing on the inside of the frontpanel to make it fit.
Again sorry about the bad phone pics, I'll try to get better at using my DSLR.
Did however increase the cap bank to 4x 10000uF Panasonic ha.
I had to mount the whole thing on the inside of the frontpanel to make it fit.
Again sorry about the bad phone pics, I'll try to get better at using my DSLR.
Attachments
I only found 3:
Class D TPA3255 PurePath™ 325W (4 Ohm) Stereo BTL, 650W (4 Ohm) Mono PBTL Configuration 12-51V
Class D TAS5630 PurePath™ 300W (4 Ohm) Stereo BTL, 600W (4 Ohm) Mono PBTL Configuration 25-50V
Class D TPA3255 Tripath™ 325W (4 Ohm) Stereo, 1000W (4 Ohm) Bridged outputs 15-65V
Class D TPA3255 PurePath™ 325W (4 Ohm) Stereo BTL, 650W (4 Ohm) Mono PBTL Configuration 12-51V
Class D TAS5630 PurePath™ 300W (4 Ohm) Stereo BTL, 600W (4 Ohm) Mono PBTL Configuration 25-50V
Class D TPA3255 Tripath™ 325W (4 Ohm) Stereo, 1000W (4 Ohm) Bridged outputs 15-65V
Last edited:
Thanks, but I went for two TA2022 boards in BTL.
One board for each channel and the added PS capacitance should produce ok sonics and power for my 15" dipole woofers.
One board for each channel and the added PS capacitance should produce ok sonics and power for my 15" dipole woofers.
I'll use either a 2x14W EL84 amp for highs/mids or build another TA2022 running that in regular stereo mode.
Only adding capacitance and moving rectifying off board.
I'll probably go with the latter as summer is comming and I really don't want the extra heat from the tubes.
Only adding capacitance and moving rectifying off board.
I'll probably go with the latter as summer is comming and I really don't want the extra heat from the tubes.
Well, I ordered another TA2022 kit.
Might as well go with two in BTL for the woofers and one in stereo for the mids/highs.
Might as well go with two in BTL for the woofers and one in stereo for the mids/highs.
Got started on the Stereo configured TA2022 that'll drive the mids/highs of my dipole speakers.
Transformer for this is a 200VA 18-0-18Vac toroidal transformer.
I'll use off-board rectifying bridges and extra capacitors(2x 10000uF Panansonic ha).
Original plan was to use Rifa PHE427 3.3uF as input caps, but there was no chance of making them fit.
So I went with 2.2uF Wima MKC4 paralleled with BC Vishay 1uF caps.
I've used other parts than the ones that came with the kit a few positions.
Transformer for this is a 200VA 18-0-18Vac toroidal transformer.
I'll use off-board rectifying bridges and extra capacitors(2x 10000uF Panansonic ha).
Original plan was to use Rifa PHE427 3.3uF as input caps, but there was no chance of making them fit.
So I went with 2.2uF Wima MKC4 paralleled with BC Vishay 1uF caps.
I've used other parts than the ones that came with the kit a few positions.
Attachments
Flipped the switch on the TA2022 BTL amp today. No puff of smoke 🙂
Wiring needs to be cleaned up, I know.
I had to make some changes to the PCB's to use "off board" rectifying and caps.
Is the TA2022 able to run without load? Ie, can I trim down DC offset without a load connected?
Are my woofers ok with that DC offset until trimmed down?
I get about +89mVdc on the board I bought a few years ago assembled (when jumpered for BTL operation). DC offset spikes to over +350mVdc at power off.
All the above without load on inputs or outputs(I had the amp powered on for about 5sec as I didn't want to risk damage if the TA2022 doesn't like running without a load).
My woofers are Dayton 15" IB's in open baffle.
Specs
I'm not sure how to proceed here...
Grateful for any and all advice.
Wiring needs to be cleaned up, I know.
I had to make some changes to the PCB's to use "off board" rectifying and caps.
Is the TA2022 able to run without load? Ie, can I trim down DC offset without a load connected?
Are my woofers ok with that DC offset until trimmed down?
I get about +89mVdc on the board I bought a few years ago assembled (when jumpered for BTL operation). DC offset spikes to over +350mVdc at power off.
All the above without load on inputs or outputs(I had the amp powered on for about 5sec as I didn't want to risk damage if the TA2022 doesn't like running without a load).
My woofers are Dayton 15" IB's in open baffle.
Specs
I'm not sure how to proceed here...
Grateful for any and all advice.
Attachments
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