How sensitive is this amp about power supply?
I used a big 13.8V adjustable supply (5-16V range) that was really good. However it was bulky (it can supply up to 30A) and I really wanted to make it compact in one enclosure. Is linear the way to go? I was thinking a 0-12 transformer, rectified to ~17VDC, to a some parallel caps would be good?
Just to make sure, this is a single supply amp, that requires 0-12 transformer right, not center tapped? Thanks!!
I used a big 13.8V adjustable supply (5-16V range) that was really good. However it was bulky (it can supply up to 30A) and I really wanted to make it compact in one enclosure. Is linear the way to go? I was thinking a 0-12 transformer, rectified to ~17VDC, to a some parallel caps would be good?
Just to make sure, this is a single supply amp, that requires 0-12 transformer right, not center tapped? Thanks!!
Yes, single supply amp. I find transformers tend to have hum unless you work hard to get rid of it. 19v SMPS and a LDO regulator to 17.5v works well too.
Toroids are low hum, if you are not willing to work to get the RF benefits of a dual bobbin. R core I believe are also low hum. By low hum I mean you don't hear it.
A regulator that can reject some RF from an SMPS is good, but a well used inductor is probably the most effective thing from a subjective POV.
A regulator that can reject some RF from an SMPS is good, but a well used inductor is probably the most effective thing from a subjective POV.
Hi, I mainly listen to spotify premium music,.I've made all the changes contained in the "guide 2" and as a power supply I use a powered stable 13 v 5A.
I wanted to ask you if Allo's multiplier works well with tda7297 or it would be better to build the zrl971 one. Thank you in advance.
Allo.com - Capacitance Multiplier
I wanted to ask you if Allo's multiplier works well with tda7297 or it would be better to build the zrl971 one. Thank you in advance.
Allo.com - Capacitance Multiplier
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Well, the SMPS I am using temporarily, are ringing. It is a brick type that is specified to give 12V output but with adjustments I am able to manage 15.1V out of it. Can you point me to a LDO (I take it, it stands for Low Drop Out regulator?) that can regulate it to let's say 15 or 14V?
Thanks. Would you suggest how and what kind of inductor I can use? Maybe a link to a schematic or discussion thread would be appreciated.
Jual LM317 DC Buck Converter Step down Linear Regulator Module - RAJADUINO | Tokopedia
Jual module xl4015 converter buck dc dc step down 5A modul - LED HOUSE | Tokopedia
Would this help to get rid of the ringing, or not? Thanks!
Jual module xl4015 converter buck dc dc step down 5A modul - LED HOUSE | Tokopedia
Would this help to get rid of the ringing, or not? Thanks!
Daniel, the ringing happened when I switched power supply unit, from lab linear supply to SMPS. I would conclude the ringing was from the power supply? 🙂 Thanks.
This comment just breaks me. It is for sure accurate, but just give me a sec, cause I lost it.
Okay, there's a practical job to be done, and it really doesn't matter if it got done on the amp board or the power board; but, what matters is that the job gets done.
He's right, but how he said it is just. . .omg. . . wonderfully accurate.
A good RC snubber properly tuned will get rid of ringing too. Check out the Quasimodo circuit by Mark Johnson. There is a GB for it here.
GB for Quasimodo Boards for Planet10
GB for Quasimodo Boards for Planet10
Yes, but it depending on the diagnosing tools and such, you may not be able to easily find the value.
Sometimes and inline resistor works easily, as low as 0.5ohm, may need a bit more.
Okay so I'm happy to report back with a massive improvement after I simplify my power supply rig. I use 12VAC 3A transformer, bridge diode soldered directly at the secondary, and one Panasonic FC 4700uF 25V at the output. I am a happy man.
Here's some pics, I put the power supply rig in a used computer PSU, it comes with IEC socket, grounded to the case, varistors and X2 rated capacitor, so it's a good start. Transformers were bolted side by side, 0-12V 3A for the amp, and 18V CT 1A for the preamp. The first is ran through a 8A 400V diode and 4700uF cap:
And the second transformer goes into a regulated supply board that brought it down to 15V.
And the second transformer goes into a regulated supply board that brought it down to 15V.