Amazing.
If you can use if you are free to use.
But I am not very suggested that such, it gives some dangerous.
...and the reason it is dangerous is ... ?
Kindly explain.
Is the cap there there for DC blocking or is there more to its function
ok, I want use a teflon caps, the value max is 0.47uf, other values is 0,22 and 0,1. What value I can use for best result? I change the 3k resistor for best accord with cap. You can suggest a combination with one value of teflon cap and a value of resistor for decent break point ?
p.s. a sound of teflon caps is very """"beautiful"""" many many trasparent
These boards are not expensive and the designer has given his recomendation of 22uF.. I suggest have a good listen to the "stock" capacitors, - then experiment and report back!
I am trying to take on board Trevmars comment that they don't need a lot of tweaking.. but no doubt I will tweak anyway, as that's part of the fun of a new toy.
I am trying to take on board Trevmars comment that they don't need a lot of tweaking.. but no doubt I will tweak anyway, as that's part of the fun of a new toy.
I agree with you, LJM is the designer of the project, He has to keep the recommendations of the datasheet But we try to improve the sound by means of tests with different components and sometimes esoteric components. The manufacturer must produce at a low price and then can only use standard components. We try to adapt the project to our hi-fi, no disrespect at the designer.
Good to know that ljm.
In the case of the hifimediy T3 the input cap cannot be removed as there's dc from the amp's side of the input itself, so it's good to confirm L20D doesn't have this issue.
Just a caution for others contemplating removal of the input cap: make sure your source allows no dc out.
In the case of the hifimediy T3 the input cap cannot be removed as there's dc from the amp's side of the input itself, so it's good to confirm L20D doesn't have this issue.
Just a caution for others contemplating removal of the input cap: make sure your source allows no dc out.
Bernie7, could you please compare sound of T3 and L20D ?
I do not need lots of power-only 40W per channel would be more than enough for mine alpair 7. I am currently listening a lm1876 based GC and i am very happy with its sound. However i would gladly like to give chance to one of these amp`s.
I do not need lots of power-only 40W per channel would be more than enough for mine alpair 7. I am currently listening a lm1876 based GC and i am very happy with its sound. However i would gladly like to give chance to one of these amp`s.
You might want to look at the thread for the L15D. ljm has a newer version of it, and it uses PS lower voltages, although it's sweet spot is still around 125w according to ljm
Hi chakija
My T3's are using Meanwell smps while the L20Ds are borrowing my Hypex linear psu, so the playing field is not exactly flat.
Both sound very good. At this point I would give the edge to the L20Ds. IMO both are very competitive against my more costly UcD kit which makes them vfm.
Wow, so apparently you can't combine shipping on the L20D amps from zoe_tsang. I'm not sure I want to pay $88 for shipping on something that's worth $300.
Anybody know if they're raising the cost of the shipping to make up for an artificially low item price?
EDIT: Seems like it. Shipping to HK is $22 per pair, too.
Anybody know if they're raising the cost of the shipping to make up for an artificially low item price?
EDIT: Seems like it. Shipping to HK is $22 per pair, too.
That seems to be a common practice with a lot of Ebay sellers, not just Hong Kong.. along1986090's price is higher, but the shipping is lower.. kind of a wash..
speaker protection
Curious about your comment on the lack of speaker protection. The reference specs seems to indicate that there is Speaker DC protection (page 25). Am I missing something?
Bernie7, IMO the T2 is really good enough for a quality audio system. It is clean enough so that it will be hard to find any speakers capable of distinguishing between the T2 and the L20D. However, the L20D measures cleaner, especially at high frequencies and high powers. I will use the T2 as a knock-about portable system run from my (Apple) 24V 2.65A power brick, and the L20D in the aluminum casing holding my main stereo amplifier. I want to get the SURE working for a suitcase-portable system I have designed, so I will get a real TDA7492 chip from Digikey or Mouser tomorrow, and replace whatever chip SURE supplied in the board
You know, the L20D performance is so good that it is really going to be hard to beat. Ljm_ljm has produced a board which is really stable, a very nice package indeed. And inexpensive as well
As for power supplies, you don't need as high a supply voltage to pump power into 4 ohm as you do into 8 ohms, but you need twice the current. The 4020 output chip on the L20D is optimized for high voltage, not high current.
As for pushing the specs a little, one tends to be cautious in view of the lack of speaker protection relay on the L20D. I am adding a board to do that for me
Hope that helps.
.
Curious about your comment on the lack of speaker protection. The reference specs seems to indicate that there is Speaker DC protection (page 25). Am I missing something?
B: yes. Reference circuit with 2 to only 2 N5551, a resistance 100 K and a 330 to determine whether the UF capacitance output have dc. (L15DX2, L20DX2)
It USES IC OUT. The way to close
In fact this way the speaker protection is not reliable, because if MOSFET damage or power of the diode damage above. Protection measures is cannot assure, no dc output.
So in my design, L15D L20D is not the this way.
And the traditional relay plan is the most safe.
It USES IC OUT. The way to close
In fact this way the speaker protection is not reliable, because if MOSFET damage or power of the diode damage above. Protection measures is cannot assure, no dc output.
So in my design, L15D L20D is not the this way.
And the traditional relay plan is the most safe.
