Hi,
Thank's for reply..
Just for info, I use 20/0/20 volts with the LM3875, and it's works well.
When you said : " the product R1 and a capacitance. 15 pf. It with R1 LPF filter."
That mean that resistor R1 have a capacitance of 15pF ?
Phil.
Thank's for reply..
Just for info, I use 20/0/20 volts with the LM3875, and it's works well.
When you said : " the product R1 and a capacitance. 15 pf. It with R1 LPF filter."
That mean that resistor R1 have a capacitance of 15pF ?
Phil.
Last edited:
Schematic?
If anyone has a schematic for the L7 they could post/pm/link I'd be really grateful. Have got one that I'd like to do some playing with 🙂
Regards, Dan
If anyone has a schematic for the L7 they could post/pm/link I'd be really grateful. Have got one that I'd like to do some playing with 🙂
Regards, Dan
Hi,
I am thinking to use 2 toroidal transformers, 34 volt 400VA each to drive 4 ohm speakers. From what I understand this should give me 48 volt rails, suggested for 4 ohm speakers. What do you think- is it a little too much or what ?
AC34-0-34 No problem.
Stereo as long as 200 va can satisfy the.
L15D Can work in very well 4 OHM.
Attachments
AC34-0-34 No problem.
Stereo as long as 200 va can satisfy the.
L15D Can work in very well 4 OHM.
where we can get that aluminum casing?
Hi,
Thank's for reply..
Just for info, I use 20/0/20 volts with the LM3875, and it's works well.
When you said : " the product R1 and a capacitance. 15 pf. It with R1 LPF filter."
That mean that resistor R1 have a capacitance of 15pF ?
Phil.
YES LM3886 There are input LPF 15 pf
3875 have is not
Hi,
I don't understand..
Can you explain with more words ?
You would said that LM3886 have 15pF capacitance at input pin 10, and LM3875 have 0 pF capacitance at input pin 7 ?
Thank's.
Phil.
I don't understand..
Can you explain with more words ?
You would said that LM3886 have 15pF capacitance at input pin 10, and LM3875 have 0 pF capacitance at input pin 7 ?
Thank's.
Phil.
Hi,
I don't understand..
Can you explain with more words ?
You would said that LM3886 have 15pF capacitance at input pin 10, and LM3875 have 0 pF capacitance at input pin 7 ?
Thank's.
Phil.
First of all,
LM3886,LM3875 Both the parameters of the chip is not the same. So the details of the circuit can't use the same circuit diagram.
In addition to the input filter. LM3886 boot quiet time delay function.
So we can't put the two chips. Together.
They're different in many places.
"Pro" model
I was about to purchase an L15D, then I noticed there is a "Pro" model which appears to have two switching Mosfets and speaker protection.
Does this protection eliminate turn off/on thumps? How much dc is required on the output to trip the relay? Is there any difference in performance between this model and the standard L15D?
I am using this amp to power a tweeter, so if the protection is not 100% then I will buy the standard model and get a protection circuit.
Thanks
I was about to purchase an L15D, then I noticed there is a "Pro" model which appears to have two switching Mosfets and speaker protection.
Does this protection eliminate turn off/on thumps? How much dc is required on the output to trip the relay? Is there any difference in performance between this model and the standard L15D?
I am using this amp to power a tweeter, so if the protection is not 100% then I will buy the standard model and get a protection circuit.
Thanks
Hello Ljm_Ljm
Please, can yon Post the wiring diagramm?
Of course. I have described in the above connection pictures. You have any questions .
Attachments
where we can get that aluminum casing?
It does not necessarily require an aluminum chassis. Iron is also possible, maybe it's cheaper .
I was about to purchase an L15D, then I noticed there is a "Pro" model which appears to have two switching Mosfets and speaker protection.
Does this protection eliminate turn off/on thumps? How much dc is required on the output to trip the relay? Is there any difference in performance between this model and the standard L15D?
I am using this amp to power a tweeter, so if the protection is not 100% then I will buy the standard model and get a protection circuit.
Thanks
L15D-PRO adds relay. But it uses a DC power supply to the relay. So it will not instantly shut down when power off . Due to the large -capacity electrolytic capacitors will persist for some time to provide voltage. Although I expect L15D-PRO will be better. However, the final results of the test yes. L15D distortion smaller. I guess the reason is the shorter of the copper on the board. Packaged together transistor . If you do not bother . L15D plus separate AC power protection would be better .
Although their differences are small .
Hi folks - first post here.
I got 2 of the 2092 L-15D boards and hooked them up to a SMPS that delivers +-48VDC.
Got everything connected - the led on the L-15 boards does not come on, and there is no sound on the output. For grins, here's a picture of the build.
The PS with no connections, measures 0 VDC, and connected to the L-15 boards, it measures +30VDC and -18VDC. Here's the power supply:
I've got some electronics experience, but not sure how to proceed. Any tips?
Thanks in advance!
I got 2 of the 2092 L-15D boards and hooked them up to a SMPS that delivers +-48VDC.
Got everything connected - the led on the L-15 boards does not come on, and there is no sound on the output. For grins, here's a picture of the build.
An externally hosted image should be here but it was not working when we last tested it.
The PS with no connections, measures 0 VDC, and connected to the L-15 boards, it measures +30VDC and -18VDC. Here's the power supply:
An externally hosted image should be here but it was not working when we last tested it.
I've got some electronics experience, but not sure how to proceed. Any tips?
Thanks in advance!
Sorry, my Google Drive images won't load -
Here is the power supply, I think it's a good one:
Amazon.com: Genssi 48V DC 7.3A 350W Regulated Switching Power Supply: Electronics
And I didn't mention that I have a star ground - every ground in the box goes to one point. Could that be a problem?
Here's another try for the pic of my build:
Here is the power supply, I think it's a good one:
Amazon.com: Genssi 48V DC 7.3A 350W Regulated Switching Power Supply: Electronics
And I didn't mention that I have a star ground - every ground in the box goes to one point. Could that be a problem?
Here's another try for the pic of my build:
An externally hosted image should be here but it was not working when we last tested it.
Attachments
Wrong power supply
Seems like you bought the wrong power supply
The L15D needs dual rail voltage , -48V ground +48V
This is a single rail voltage power supply , only + 48V DC
Sorry , Cheers
Rens
Sorry, my Google Drive images won't load -
Here is the power supply, I think it's a good one:
Amazon.com: Genssi 48V DC 7.3A 350W Regulated Switching Power Supply: Electronics
And I didn't mention that I have a star ground - every ground in the box goes to one point. Could that be a problem?
Here's another try for the pic of my build:
An externally hosted image should be here but it was not working when we last tested it.
Seems like you bought the wrong power supply

The L15D needs dual rail voltage , -48V ground +48V
This is a single rail voltage power supply , only + 48V DC
Sorry , Cheers
Rens
Sorry, my Google Drive images won't load -
Here is the power supply, I think it's a good one:
Amazon.com: Genssi 48V DC 7.3A 350W Regulated Switching Power Supply: Electronics
And I didn't mention that I have a star ground - every ground in the box goes to one point. Could that be a problem?
Here's another try for the pic of my build:
An externally hosted image should be here but it was not working when we last tested it.
looks like its a dual rail (+/-) from the picture posted in amazon but its kinda low in voltage. btw I also tested that amp using SMPS and i didn't like the sound, soundstage is so narrow/thin and the low end disappear so i switch back to linear PSU
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