Interesting thread. Sounds like the kid did good, better sound without releasing the 'magic smoke' (lol)!
I ordered one of these off e-bay, it should be here sometime next week. Guess I'll have to wait and see which model I get (with or without the protection relay). I'm kind of hoping it's the older one, since there are so many documented mods in this thread.
After all, sometimes the journey counts as much as reaching the destination.
IF you have one of the new models with the relay, you should check the output voltage of the power supply. It has over voltage shut down above 13.8volts. It may be reseting when you unplug it and playing a few notes of the reserve in the capacitors
youre right
so i tested my adapter, its at around 17 volts
. even though it claims 12v... gotta look for another one then? or is it easy to construct something that will knock off 5 volts?
so i tested my adapter, its at around 17 volts
. even though it claims 12v... gotta look for another one then? or is it easy to construct something that will knock off 5 volts?I've bought two of these recently. The first one had the new relay with the new circuit board that Frank posted a picture of. My relay took about 20-30min to finally click on the first time I plugged it in. Now I just leave it on (I have it connected to the pre-amp outputs on a receiver). Oddly, the relay only seems to click on when I have it hooked up to the cheap-o wall wart transformer that came with it - it doesn't want to click on when I have it connected to a 12v 2A regulated supply.
I just got a second one today (ordered from PE), and guess what?! IT HAS A TONE/DIRECT BUTTON ON THE FRONT! This switch will bypass the treble/bass controls. So far it seems to be working great. I haven't taken it apart to take pictures of it yet.
I just got a second one today (ordered from PE), and guess what?! IT HAS A TONE/DIRECT BUTTON ON THE FRONT! This switch will bypass the treble/bass controls. So far it seems to be working great. I haven't taken it apart to take pictures of it yet.
easy to construct
I had a similar situation. I found some diodes with volt and amp ratings some what larger than the ratings on the adapter. I then split the + and - wires from each other a little ways back from the plug. I then replaced a section of the positive wire with a string of diodes. Since the forward voltage drop across the diodes varies with the model,you have to do a little testing to determine how many will be needed. (if I remember mine were a round 0.7V) With this amp I wood shoot for 13.5v. Next I cut the + wire with the diodes so it is = length with the - wire, soldered all connections and taped first the + wire then both wires together. I did this to a old IBM unregulated adapter and it worked very well.
so i tested my adapter, its at around 17 volts
I had a similar situation. I found some diodes with volt and amp ratings some what larger than the ratings on the adapter. I then split the + and - wires from each other a little ways back from the plug. I then replaced a section of the positive wire with a string of diodes. Since the forward voltage drop across the diodes varies with the model,you have to do a little testing to determine how many will be needed. (if I remember mine were a round 0.7V) With this amp I wood shoot for 13.5v. Next I cut the + wire with the diodes so it is = length with the - wire, soldered all connections and taped first the + wire then both wires together. I did this to a old IBM unregulated adapter and it worked very well.
Hi Everyone,
New to this forum, great stuff here. This thread is the reason why I bought 2 LePai T-amps, 1 to keep stock and the second to modify with all the great info here.
I ordered 2 from parts express, got a couple of day later. And just as jarros commented above it comes with a tone defeat push button switch. I opened one up and to my surprise and to my dismay it is a surface mount double sided board, some caps, inductors and relay are thru hole. It also have 2 op-amps JRC4558, why would it have 2? Any idea?
Looks beautiful! Already has some of the mods here implemented, nothing hooked to the mute pin, tone defeat. Values of components are not marked on the board. Going to make moding a little more difficult.
I try to get a pic soon.
Sounds great to me, it’s my first T-amp.
New to this forum, great stuff here. This thread is the reason why I bought 2 LePai T-amps, 1 to keep stock and the second to modify with all the great info here.
I ordered 2 from parts express, got a couple of day later. And just as jarros commented above it comes with a tone defeat push button switch. I opened one up and to my surprise and to my dismay it is a surface mount double sided board, some caps, inductors and relay are thru hole. It also have 2 op-amps JRC4558, why would it have 2? Any idea?
Looks beautiful! Already has some of the mods here implemented, nothing hooked to the mute pin, tone defeat. Values of components are not marked on the board. Going to make moding a little more difficult.
I try to get a pic soon.
Sounds great to me, it’s my first T-amp.
Is the power switch hooked up to the sleep/mute pin or does it kill the power all the way? On the old one, it only muted it (bad for batteries). Based on what you've said, the new one actually cuts power (much better).
Also, how's the sound quality and the startup? Any clicks? Any delay?
Thanks,
Nick
PE has substituted a Lepai LP-V3 for the TA2020 you ordered:
LePai Computer Amplifier LP-V3 Hi-Fi Enthusiast of high-quali...USD 10.82/Piece Wholesale Price at DHgate.com
It uses a TDA8566 chip instead of the TA2020.
I KNEW IT!!!
I like PE, but not if there going to pull this ****. That's horrible. Knew it was too good to be true. I'm glad that I didn't jump the gun on these. Ordered from my friend in China thankfully.
If I were you, I would send them back and demand a refund. That's false advertising!
I'm really sorry to hear that.
It is definitely a Tripath TA2020, at least that is what is printed on the side of the chip. It is not the one the previous poster showed, does not have the word “bose” on it.
As far as clicks, it has a relay after the chip, inductor and caps and before the speaker terminals. However, it does not eliminate turn on and turn off thumps, even though there is a delay.
The Power switch is not hooked up to the mute switch. I would have to take it apart to see if it is hooked up to the sleep pin, I do not know. I do know that the blue LED’s turn off when the switch is turned off.
Does anyone know why it would have 2 op-amps, JRC4558
Also to typical surface mount components have a better tolerance than thru-hole components?
I will have to say that the bass/treble controls do an ok job. When both are at 12:00 position, just slightly more bass than when defeated with the tone switch.
I sound really good to me, this is my first T-amp. And now I want to mod one of them.
As far as clicks, it has a relay after the chip, inductor and caps and before the speaker terminals. However, it does not eliminate turn on and turn off thumps, even though there is a delay.
The Power switch is not hooked up to the mute switch. I would have to take it apart to see if it is hooked up to the sleep pin, I do not know. I do know that the blue LED’s turn off when the switch is turned off.
Does anyone know why it would have 2 op-amps, JRC4558
Also to typical surface mount components have a better tolerance than thru-hole components?
I will have to say that the bass/treble controls do an ok job. When both are at 12:00 position, just slightly more bass than when defeated with the tone switch.
I sound really good to me, this is my first T-amp. And now I want to mod one of them.
I'm really confused now. Could you please post some pictures? Perhaps we could clear all this up with some pictures.
Thanks,
Nicholas
I've been lurking on this for a while, but the unit I received is a completely new board. Over half of the components are now surface mount, and there's a tone circuit bypass button on the front panel. Interestingly when I press this button I get nothing but static, so I guess it's actually a tone elimination circuit.
Sorry, no camera working ATM.
Kurt
Sorry, no camera working ATM.
Kurt
Just opened my unit from PE that arrived today..it is the new one with the tone bypass.black case..says LP-2020A+.the chip is the TA 2020. Most all the board is pass thru still. the power stiffener on the left facing the front is 3300 16 v 105c japan.no extra diode there that i can tell. there is a big square black box right behind the speaker terminals that says OMRON g5pa-2 12volt. [I am new to all this so bear with me.] there still is a mild jump on turnon. I tested it at 10 o'clock setting with some infinity reference 2000.2 speakers and the bass and treble sound quite good with dire straits and cowboy junkies.Hope this helps.
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