Well, the guy had a good rating. Low total cost. Mouser, Jameco, etc have shipping charges that are so high that you need to buy a lot of stuff to make it worth it. I will push for a return with this guy, and I will likely get my money back. Just a waste of time. Trying another eBay seller, also US located, with TI NE5532A ten for about $10 shipped.
The image is not visible.hstbeto sells 5532s that have a logo like the ones on the left in the picture.
Thanks mga2009 for bringing this deal to my attention. I was able to pick up a couple and build a streaming BTL amp with them and a IQaudIO Pi-DAC Pro (balanced out) running Volumio. I crammed them in a BZ1907D chassis with a meanwell RS-15-5 power supply and an Adafruit rotary encoder (with debounce circuit). With the little listening I have done so far, the amp sounds great with a lot of headroom and a low noise floor.
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It wasn't hard getting them out. I removed the back panel and was able to unscrew and disconnect the amps to remove them. I'm not using the preamp board as I have balanced output from the Pi-DAC Pro and others had commented that it isn't the same quality as the ICEpower modules. The modules also come with the wiring harnesses which is a big plus.
Has anyone tried the following layout for a stereo setup? I'm a little concerned about cable routing being an issue.
Plan is to unhook the pins for the signal in JST connectors going into the preamp, then hook them straight into the 125asx2. Hopefully that way I don't have to get a soldering iron for a one off mod. If that doesn't work maybe I can splice the blue and red signal wires into the rainbow ones so I don't have to mess around with finding the right JST connectors?
Then remove the preamp board and twist that power cable because I might as well.
Seems like most of the people in this thread are just tearing out the 125asx2 module and the wires for completely new cases and layouts?
Plan is to unhook the pins for the signal in JST connectors going into the preamp, then hook them straight into the 125asx2. Hopefully that way I don't have to get a soldering iron for a one off mod. If that doesn't work maybe I can splice the blue and red signal wires into the rainbow ones so I don't have to mess around with finding the right JST connectors?
Then remove the preamp board and twist that power cable because I might as well.
Seems like most of the people in this thread are just tearing out the 125asx2 module and the wires for completely new cases and layouts?
I received my FA-500 today and runnin it in bridged mode, driving 1 channel, against my Parasound HCA 2200 on the other channel...and the difference in the 2 is next to none !!!
This is a very capable amp for $100. Eventually I'm going to use it in 2 channel mode in the garage, but had to do this comparison 1st.
This is a very capable amp for $100. Eventually I'm going to use it in 2 channel mode in the garage, but had to do this comparison 1st.
I am looking forward to giving mine a test drive.
Once that is out of the way, it would seem to be wise to get them into a new chassis where I can bypass the preamp and run them as monoblocks.
What other mods have people done on these so far? What are recommended? Anyone have photos of theirs modded or recased?
Once that is out of the way, it would seem to be wise to get them into a new chassis where I can bypass the preamp and run them as monoblocks.
What other mods have people done on these so far? What are recommended? Anyone have photos of theirs modded or recased?
A new tone board.
I need your your input before I start routing. I need your input to know if this is a good idea or the "crazy idea" of the day
Will there be any interest to a board based on the design and routing of the theslowdiyer project as stated in post #170
My idea, and not sure if is space feasible, will be to make the psu and the buffer into a single board capable of fitting inside the gento case. Not looking to profit from this project (as it is not my design) , boards will be available to order from osh (x3 minimum) by yourself or at face value from me ( I order my board from dirtypcb.com and minimum order are 10). Me, I only need two.
In my experience, if the traces and holes are kept above the fab minimums, the dirty pcb are pretty nice. Furthermore the non eing finish seem to help for through hole soldering
Not interested in balanced or bridging at this point. I want to use it as a dsp driven amp for an active two way. The way I envision it is to add a pot to the ghento case (x2 channels) and place the tone board inside.
PD: The gento case seems like a good starting point but any other case can be considered. A case to hold two amps and two buffers ( for a total of 4 channels) could also be good.
Please comment.
I need your your input before I start routing. I need your input to know if this is a good idea or the "crazy idea" of the day
Will there be any interest to a board based on the design and routing of the theslowdiyer project as stated in post #170
My idea, and not sure if is space feasible, will be to make the psu and the buffer into a single board capable of fitting inside the gento case. Not looking to profit from this project (as it is not my design) , boards will be available to order from osh (x3 minimum) by yourself or at face value from me ( I order my board from dirtypcb.com and minimum order are 10). Me, I only need two.
In my experience, if the traces and holes are kept above the fab minimums, the dirty pcb are pretty nice. Furthermore the non eing finish seem to help for through hole soldering
Not interested in balanced or bridging at this point. I want to use it as a dsp driven amp for an active two way. The way I envision it is to add a pot to the ghento case (x2 channels) and place the tone board inside.
PD: The gento case seems like a good starting point but any other case can be considered. A case to hold two amps and two buffers ( for a total of 4 channels) could also be good.
Please comment.
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Hi Frabor,
As the boards are stackable I think it's possible to fit them in Ghent case.
The populated buffer boards is very thin, about 1cm high, so two boards stacked with spacers can fit IMHO in a 125 ASX2 Ghent case.
PS : I'm in the same projact, but I've not statued on the case and not poplated the PSU board
. FIY Yamaha wxa-50 feature all thoses things, buffer, volume pot, 125 ASX2 module, aluminium case and more for about 400 € not sure DIY is really cheaper BR,
Pascal
Hi Pascal,
The Yamaha wxa-50 looks great but at 400 euros /500 usd can be expensive for a multi channel (4 channels = 1000). Even including the price of the cases, diy pays for a nice minidsp, interconnects, cables and a dinner, diy seem a cheaper alternative
I like the 125 ASX2 modules as they came with the power supply built in, but looking at the size of the supply I have my serious doubts that they can support RMS stated value for more than a couple of minutes without derrating. In order to provide full mono rating you need a 20 amp power supply and this modules do not look capable of such current reliably.
After reviewing the data sheet, maximum power is 65 Watts per channel x2 continuous or for 400 watts mono for 80 seconds before thermal shutdown. Note that it is not stated if this is rms or peak, so for all effect assume peak.
If cost is the single issue wondon has great yet affordable blocks. As examples the highly rated aa-ab32313 and the mono version AA-AB31511 (below on pic) that come with a buffer and a $5 optional volume control. My first attempt to a Class d amp was with a mono block 500 watts from sure wondom and a minidsp. This particular module (both the stereo and the mono has great reviews) and it comes with the buffer and a "volume control". Only mod to the wondom was a low noise high flow noctua fan. Furthermore the wondon with the fan mod can provide more power that theReusing a computer rack case is the way to go for low price as a 2u 17" case can hold several modules and or power supplies. In this particular one (got the power supplies used) I spent about $140. The rest was reused.
A nice four channel 125 ASX2 amp with a minidsp 2x4 hd, with the existing buffer boards and rack mount case can be built for about than $825 (asx2: 150x2, buffer/ps $100, case $100 Interconnects $100 minidsp 2x4 HD with remote $225). That is a lot of money but still less than two of the wxa-50 and you get for free a remote control and a minidsp 2x4 hd.
I am going to hold on the routing of the boards. Maybe as you stated there the other boards can fit nicely and there is no sense on a re-route and fab.
Francis.
The Yamaha wxa-50 looks great but at 400 euros /500 usd can be expensive for a multi channel (4 channels = 1000). Even including the price of the cases, diy pays for a nice minidsp, interconnects, cables and a dinner, diy seem a cheaper alternative
I like the 125 ASX2 modules as they came with the power supply built in, but looking at the size of the supply I have my serious doubts that they can support RMS stated value for more than a couple of minutes without derrating. In order to provide full mono rating you need a 20 amp power supply and this modules do not look capable of such current reliably.
After reviewing the data sheet, maximum power is 65 Watts per channel x2 continuous or for 400 watts mono for 80 seconds before thermal shutdown. Note that it is not stated if this is rms or peak, so for all effect assume peak.
If cost is the single issue wondon has great yet affordable blocks. As examples the highly rated aa-ab32313 and the mono version AA-AB31511 (below on pic) that come with a buffer and a $5 optional volume control. My first attempt to a Class d amp was with a mono block 500 watts from sure wondom and a minidsp. This particular module (both the stereo and the mono has great reviews) and it comes with the buffer and a "volume control". Only mod to the wondom was a low noise high flow noctua fan. Furthermore the wondon with the fan mod can provide more power that theReusing a computer rack case is the way to go for low price as a 2u 17" case can hold several modules and or power supplies. In this particular one (got the power supplies used) I spent about $140. The rest was reused.
A nice four channel 125 ASX2 amp with a minidsp 2x4 hd, with the existing buffer boards and rack mount case can be built for about than $825 (asx2: 150x2, buffer/ps $100, case $100 Interconnects $100 minidsp 2x4 HD with remote $225). That is a lot of money but still less than two of the wxa-50 and you get for free a remote control and a minidsp 2x4 hd.
I am going to hold on the routing of the boards. Maybe as you stated there the other boards can fit nicely and there is no sense on a re-route and fab.
Francis.
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I've just modded my Vocopro 125ASX2 amp to be without any kind of input board/buffer, now I have direct RCA connection to the board, like with a Ghent kit for example.
My problem now is that the amp is extremely loud, I have to put my preamp to something like 8 'clock position, and it starts from 7 o'clock and goes till 5 o'clock. I believe at such low position it must distort quite a lot.
What can I do? Do I understand well that I cannot put any potentiometer (like and SMD DACT for example) between the preamp and the amp as it would ruin the sound?
So my only option is to put an SMD DACT before the preamp module? I don't want to use digital only volume control as I'm afraid a bad mouse click could destroy my speaker.
My problem now is that the amp is extremely loud, I have to put my preamp to something like 8 'clock position, and it starts from 7 o'clock and goes till 5 o'clock. I believe at such low position it must distort quite a lot.
What can I do? Do I understand well that I cannot put any potentiometer (like and SMD DACT for example) between the preamp and the amp as it would ruin the sound?
So my only option is to put an SMD DACT before the preamp module? I don't want to use digital only volume control as I'm afraid a bad mouse click could destroy my speaker.
I still haven't pulled mine out but am wondering what the best course of action will be once I get them set up... Having the poor quality preamp bypassed sounds like a good start, but beyond that, no clue what if anything has been successfully done with them.
I would advocate for an input control on the amp, as I am still apprehensive about trusting computers 100% to do what you want and when. No way I'd want a $99 amp taking out $1000 speakers... But that's just me. Some people like to do electrical without disconnecting fuses too... But that don't make it seem right to me
I would advocate for an input control on the amp, as I am still apprehensive about trusting computers 100% to do what you want and when. No way I'd want a $99 amp taking out $1000 speakers... But that's just me. Some people like to do electrical without disconnecting fuses too... But that don't make it seem right to me
The most simple input stage for an amp is made from two resistors. As usually there already is an in series resistor at any amps input, you might get away with one...from input signal to input ground. If you have a powerful pre amp, try 600 Ohm to ground, if your pre is not happy in driving higher current, try 10k Ohm. You will have to open up the pre much more, but this way you reduce noise at the input, as it is reduced by the 600 Ohm resistor too. The ratio of noise to signal gets much better. There will be some kind of best combination with any amp /pre amp combination.
As always: If you tune your system for an optimum, you might lose some of its universal compatibility.
I
As always: If you tune your system for an optimum, you might lose some of its universal compatibility.
I
I believe the preamp in my fa-500 has died. The amp still turns on and plays but sounds very tinney and staticy, also the power LED which is powered off the preamp board no longer lights up....Can someone coach me through what I need to do to bypass the preamp and connect the rca inputs to the 125asx module directly. My 1st question is the wires coming from the rca inputs have 5 wires not the 4 I was expecting. What's the 5th wire about?
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