"The Wiener" TPA3118 amplifier, group buy #3 + "Wiener Pro" prototypes.

[boylah]

loafimus: 4 x bare PBTL PCB + 4 x microcontroller
ChuckT: fully assembled stereo Wiener + fully assembled Pro
DawgNo1: 2x PBTL 3118 fully built.
jonners: 1x stereo fully assembled Pro
Pyjamas Before Chris: 1x stereo fully assembled Pro
wushuliu: 1 Pair Assembled PBTL MINUS CONNECTORS - 4 ohm
hepmusic 1 stereo 3118 8 ohm fully assembled
rhing: 1 Weiner 3 Pro, fully assembled
williamau: 1 Pair Assembled PBTL - 8 ohm
BK856er: 1x bare Wiener Pro + microcontroller
shochu: 1x fully assembled stereo + filter & thermal kits
boylah: 1xstereo 3118 8 ohm fully assembled

Sign me up!

 

[ChuckT]

Gmarsh, you got a large order


loafimus: 4 x bare PBTL PCB + 4 x microcontroller
DawgNo1: 2x PBTL 3118 fully built.
jonners: 1x stereo fully assembled Pro
Pyjamas Before Chris: 1x stereo fully assembled Pro
wushuliu: 1 Pair Assembled PBTL MINUS CONNECTORS - 4 ohm
hepmusic 1 stereo 3118 8 ohm fully assembled
rhing: 1 Weiner 3 Pro, fully assembled
williamau: 1 Pair Assembled PBTL - 8 ohm
BK856er: 1x bare Wiener Pro + microcontroller
shochu: 1x fully assembled stereo + filter & thermal kits
TigerFoo: 1x fully assembled stereo + filter and thermal kits
boylah: 1xstereo 3118 8 ohm fully assembled

ChuckT 18 X full assembled TPA3118 ,
4 x full assembled TPA3250
(filter, thermal kits to be confirm)

 

[gmarsh]

Thanks, Chuck! That puts me up to 28 assembled "wiener classics", so I'll be hitting qty 25/50/100 discounts on a bunch of parts. Group buy is most certainly going ahead right now

Anyway I'm fixing a solid state amp for someone right now, and what I thought was a quick "throw parts at it, hope for the best" job has turned into a bit of a time pit. Once that's off my plate, I'll get the part price spreadsheets done, finalize pricing and start officially taking orders.

 

[Fjd]

Gmarsh, you got a large order


loafimus: 4 x bare PBTL PCB + 4 x microcontroller
DawgNo1: 2x PBTL 3118 fully built.
jonners: 1x stereo fully assembled Pro
Pyjamas Before Chris: 1x stereo fully assembled Pro
wushuliu: 1 Pair Assembled PBTL MINUS CONNECTORS - 4 ohm
hepmusic 1 stereo 3118 8 ohm fully assembled
rhing: 1 Weiner 3 Pro, fully assembled
williamau: 1 Pair Assembled PBTL - 8 ohm
BK856er: 1x bare Wiener Pro + microcontroller
shochu: 1x fully assembled stereo + filter & thermal kits
TigerFoo: 1x fully assembled stereo + filter and thermal kits
boylah: 1xstereo 3118 8 ohm fully assembled

ChuckT 18 X full assembled TPA3118 ,
4 x full assembled TPA3250
(filter, thermal kits to be confirm)

loafimus: 4 x bare PBTL PCB + 4 x microcontroller
DawgNo1: 2x PBTL 3118 fully built.
jonners: 1x stereo fully assembled Pro
Pyjamas Before Chris: 1x stereo fully assembled Pro
wushuliu: 1 Pair Assembled PBTL MINUS CONNECTORS - 4 ohm
hepmusic 1 stereo 3118 8 ohm fully assembled
rhing: 1 Weiner 3 Pro, fully assembled
williamau: 1 Pair Assembled PBTL - 8 ohm
BK856er: 1x bare Wiener Pro + microcontroller
shochu: 1x fully assembled stereo + filter & thermal kits
TigerFoo: 1x fully assembled stereo + filter and thermal kits
boylah: 1xstereo 3118 8 ohm fully assembled
ChuckT 18 X full assembled TPA3118, 4 x full assembled TPA3250 (filter, thermal kits to be confirm)
Fjd: 2 x [Stereo Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 2 x [PBTL Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 1 x [The Wiener Pro 4 ohm, fully assembled and tested]

 

[ChuckT]

Quick question, is the tpa3118 configure already with balance input or single end? or is it just a change of jumper?

 

[DawgNo1]

Gmarsh, you got a large order


loafimus: 4 x bare PBTL PCB + 4 x microcontroller
jonners: 1x stereo fully assembled Pro
Pyjamas Before Chris: 1x stereo fully assembled Pro
wushuliu: 1 Pair Assembled PBTL MINUS CONNECTORS - 4 ohm
hepmusic 1 stereo 3118 8 ohm fully assembled
rhing: 1 Weiner 3 Pro, fully assembled
williamau: 1 Pair Assembled PBTL - 8 ohm
BK856er: 1x bare Wiener Pro + microcontroller
shochu: 1x fully assembled stereo + filter & thermal kits
TigerFoo: 1x fully assembled stereo + filter and thermal kits
boylah: 1xstereo 3118 8 ohm fully assembled

ChuckT 18 X full assembled TPA3118 ,
4 x full assembled TPA3250
(filter, thermal kits to be confirm)

Sorry I am going to have to miss this one now.

 

[wushuliu]

quick question: if i want to replace the input caps with larger poly caps, where should I solder the lead in? This layout is a little different from the YJ board. Can I bypass those first resistors?

 

[Fjd]

Sorry I am going to have to miss this one now.

I'm not sure why you removed my name too, but I will add it back.


loafimus: 4 x bare PBTL PCB + 4 x microcontroller
jonners: 1x stereo fully assembled Pro
Pyjamas Before Chris: 1x stereo fully assembled Pro
wushuliu: 1 Pair Assembled PBTL MINUS CONNECTORS - 4 ohm
hepmusic 1 stereo 3118 8 ohm fully assembled
rhing: 1 Weiner 3 Pro, fully assembled
williamau: 1 Pair Assembled PBTL - 8 ohm
BK856er: 1x bare Wiener Pro + microcontroller
shochu: 1x fully assembled stereo + filter & thermal kits
TigerFoo: 1x fully assembled stereo + filter and thermal kits
boylah: 1xstereo 3118 8 ohm fully assembled
ChuckT 18 X full assembled TPA3118, 4 x full assembled TPA3250 (filter, thermal kits to be confirm)
Fjd: 2 x [Stereo Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 2 x [PBTL Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 1 x [The Wiener Pro 4 ohm, fully assembled and tested]

 

[gmarsh]

quick question: if i want to replace the input caps with larger poly caps, where should I solder the lead in? This layout is a little different from the YJ board. Can I bypass those first resistors?

There's only two caps in the input circuit:

- feedback caps on the OPA1632. These provide low pass filtering, to keep out high frequency trash that might intermodulate with the PWM carrier in the TPA and end up audible on the output. They also help keep the chip stable. They're C0G/NPO ceramics, I wouldn't replace them with anything else.
- Coupling caps from the OPA1632 output to the TPA3250. Right now these are 1.5uF/63V film (Epcos B32529). I wouldn't suggest anything other than a film capacitor or bipolar electrolytic in this role, value range 1uF-4.7uF.

To change them to something else, desolder the old ones (the four rectangular caps to the right of the electrolytics) and solder in the new ones somehow. If you air-wire the new caps, try to keep them away from the output inductors and the SMPS inductor. Both are shielded inductors, but a loop of wire sitting next to them might still pick something up.

There's also decoupling capacitors on the op-amps, which are a 0.1uF/25V X7R per rail per op-amp, next to a 100uF (I think, I haven't confirmed the value) polymer electrolytic. I wouldn't change either of these things.

 

[gmarsh]

Quick question, is the tpa3118 configure already with balance input or single end? or is it just a change of jumper?

The card has differential inputs, with +/-/GND pins. (GND was missing on the previous stereo card, it's in there now.)

To hook up single ended input sources, connect input shield to - and input signal to +. And either connect the input shield to GND also, or ensure that the source ground and the Wiener power supply ground are the same by some other means.

For differential sources, input +/- goes to card +/- and cable/signal ground ("pin 1" on an XLR) goes to GND.

 

[takayama69]

I am very keen on a TPA3250/51 amp. The 3251 might just be to powerful for my purposes. So I found this thread..

For me..a noob on amps..I just want toplug and play: one source, add a 32 V switching DC power ..Connect my 8 ohm speakers.
A 50 K ohm potentiometer or so could controll the input from a RCA signal.

So. Enlight me pls..

1. What can the micro controllers do? Do you have a pic of them? Can they be connected to old school knobs and switches to make a amp with large controlls?
2 The filter mentioned...what does it filter?
3. Do i need som extra "power bank" of caps for smooth operations ?

Right answers will result in an order...

 

[gmarsh]

I am very keen on a TPA3250/51 amp. The 3251 might just be to powerful for my purposes. So I found this thread..

For me..a noob on amps..I just want toplug and play: one source, add a 32 V switching DC power ..Connect my 8 ohm speakers.
A 50 K ohm potentiometer or so could controll the input from a RCA signal.

So. Enlight me pls..

1. What can the micro controllers do? Do you have a pic of them? Can they be connected to old school knobs and switches to make a amp with large controlls?
2 The filter mentioned...what does it filter?
3. Do i need som extra "power bank" of caps for smooth operations ?

Right answers will result in an order...

The TPA3250 and 3251 are the same chip, the 3250 (which I'm using here) has the thermal pad facing downwards and is heatsinked to the PCB, the 3251 has the thermal pad facing upwards and requires a heatsink mounted to the top. With the same power supply voltage, the 3250 and 3251 will provide the same output power.

The card should be "plug and play" as you describe. I'll draw up a sketch later of how to wire it up.

Answering your questions:

(1) The microcontroller is used to manage the TPA3250 chip, it does a bunch of things:

- It continuously monitors the power supply voltage. If it suddenly drops (if you unplugged the power supply, say) it mutes the amplifier, which prevents a turn-off pop.
- It provides a turn-on delay, taking the TPA3250 out of reset and giving time for the input coupling caps to charge, before unmuting it. This prevents a turn-on pop.
- It monitors the fault/status outputs of the chips, handles any corrective action required, and drives the bicolor status LED. Green = all good, orange = clipping, red = something bad.
- And it watches the standby jumper input.

(2) There's only really two filters on this card, a lowpass filter in the input stage (-3dB at 45ish KHz) which keeps HF trash out of the amp that may end up audible, and the output LC filter which reconstructs the audio output.

(3) Depends on what the power supply is. If it's from a SMPS or other off the shelf DC supply, you should be fine with onboard capacitance. If your power supply is a rectified 50/60Hz transformer secondary, you'll want some bulk capacitance after the rectifier.

 

[ChuckT]

Just wondering if I use a transformer for balance input into the Wiener, can I bypass or remove the coupling caps. Will the transformer secondary see any DC voltage if I don't connect the secondary to ground?

BTW, when is the payment date, I am still finalizing the details on my side.

 

[takayama69]

Thanks a lot gmarsh!

Comforting answers..+ a cool design + Coil Craft -Cravings + some refund on the taxes..
I'm in...

 

[takayama69]

loafimus: 4 x bare PBTL PCB + 4 x microcontroller
jonners: 1x stereo fully assembled Pro
Pyjamas Before Chris: 1x stereo fully assembled Pro
wushuliu: 1 Pair Assembled PBTL MINUS CONNECTORS - 4 ohm
hepmusic 1 stereo 3118 8 ohm fully assembled
rhing: 1 Weiner 3 Pro, fully assembled
williamau: 1 Pair Assembled PBTL - 8 ohm
BK856er: 1x bare Wiener Pro + microcontroller
shochu: 1x fully assembled stereo + filter & thermal kits
TigerFoo: 1x fully assembled stereo + filter and thermal kits
boylah: 1xstereo 3118 8 ohm fully assembled
ChuckT 18 X full assembled TPA3118, 4 x full assembled TPA3250 (filter, thermal kits to be confirm)
Fjd: 2 x [Stereo Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 2 x [PBTL Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 1 x [The Wiener Pro 4 ohm, fully assembled and tested]
Takayama69 a.k.a Anders Högberg: 1x TPA3250 all inclusive. 8 Ohm-version.

 

[gmarsh]

Just wondering if I use a transformer for balance input into the Wiener, can I bypass or remove the coupling caps. Will the transformer secondary see any DC voltage if I don't connect the secondary to ground?

BTW, when is the payment date, I am still finalizing the details on my side.

On the standard stereo Wiener, there's 30K resistors on each input to ground (R29 through R32) that should be removed if you jumper over the coupling caps and use the terminal block.

Alternatively, you can connect the transformer secondary windings to the TPA-facing side of the capacitor footprints, and leave the resistors in place.

There will be a couple volts of DC voltage on the transformer secondary if you bypass the caps, so if there's a center tap on the secondary, either float it, or connect a capacitor between the secondary tap and ground. I'd recommend the latter, as it will shunt any HF EMI coming through the transformer's interwinding capacitance to ground.

edit: Payment date is "soon" - hopefully before the end of this week. I think I'm done moving parts around on the Pro, but still have to run off the BOM, confirm component values, etc... and cost the whole shot. Once I've got real established numbers for the price of things, I'll get it done. Right now I'm trying to find a suitable 2-lead socket that would allow a through-hole gain adjust resistor to be stuffed in, without having to solder it to the board. I could put down pots but matching them between the channels would require the end user to have a DMM...

 

[loafimus]

Well, now since the Pro has the CoilCrafts, I think it's caught the attention of my brother also. Hopefully this doesn't change your PCB order too much, but the Pro sounds pretty awesome.

Also, would it be possible to order an extra PCB stencil for the Pro from Elecrow when you order yours? Just add it on to my order?

loafimus: 6 x bare Pro PCB w/ microcontrollers
jonners: 1x stereo fully assembled Pro
Pyjamas Before Chris: 1x stereo fully assembled Pro
wushuliu: 1 Pair Assembled PBTL MINUS CONNECTORS - 4 ohm
hepmusic 1 stereo 3118 8 ohm fully assembled
rhing: 1 Weiner 3 Pro, fully assembled
williamau: 1 Pair Assembled PBTL - 8 ohm
BK856er: 1x bare Wiener Pro + microcontroller
shochu: 1x fully assembled stereo + filter & thermal kits
TigerFoo: 1x fully assembled stereo + filter and thermal kits
boylah: 1xstereo 3118 8 ohm fully assembled
ChuckT 18 X full assembled TPA3118, 4 x full assembled TPA3250 (filter, thermal kits to be confirm)
Fjd: 2 x [Stereo Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 2 x [PBTL Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 1 x [The Wiener Pro 4 ohm, fully assembled and tested]
Takayama69 a.k.a Anders Högberg: 1x TPA3250 all inclusive. 8 Ohm-version.

 

[gmarsh]

I can do that if you want.

Though a metal stencil from Elecrow is $16 USD, probably close to $20 USD including customs/shipping/brokerage to get it in my hands. OSHStencils plastic ones are good for 25-50 uses they say, and will cost about $10 USD based on 15 square inches.

 

[loafimus]

Ah, no biggie then. We'll do OSHStencils.

Thanks.

 

[mabu0815]

Adding my interest:

loafimus: 6 x bare Pro PCB w/ microcontrollers
jonners: 1x stereo fully assembled Pro
Pyjamas Before Chris: 1x stereo fully assembled Pro
wushuliu: 1 Pair Assembled PBTL MINUS CONNECTORS - 4 ohm
hepmusic 1 stereo 3118 8 ohm fully assembled
rhing: 1 Weiner 3 Pro, fully assembled
williamau: 1 Pair Assembled PBTL - 8 ohm
BK856er: 1x bare Wiener Pro + microcontroller
shochu: 1x fully assembled stereo + filter & thermal kits
TigerFoo: 1x fully assembled stereo + filter and thermal kits
boylah: 1xstereo 3118 8 ohm fully assembled
ChuckT 18 X full assembled TPA3118, 4 x full assembled TPA3250 (filter, thermal kits to be confirm)
Fjd: 2 x [Stereo Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 2 x [PBTL Wiener 4 ohm, fully assembled and tested, filter kit, thermal kit] + 1 x [The Wiener Pro 4 ohm, fully assembled and tested]
Takayama69 a.k.a Anders Högberg: 1x TPA3250 all inclusive. 8 Ohm-version.
mabu0815: 1x Stereo Wiener PCB + 2x PBTL PCBs + 3x microcontrollers