That's a great record!Found this at a shop the other day... Most of the time I'm not in the way...
Found this at a shop the other day... Most of the time I'm not in the way...
It's an awesome recording.
I got it both in LP and CD. It's also available on Tidal HiFi.
SET is between SIT and full MOS, regarding power
plenty enough, who cares ......
no THD vs. Power graphs, working with ARTA, still not grown enough for that Voodoo
Couple questions before fire up.
In the fireup instructions, it says "Ground negative input" and also says "Also ground positive input." The first time I read the thread I simply assumed it was talking about having shorting jacks in the inputs. Now that I am looking more carefully while getting ready to put into practice, it appears to be referring to something else. What steps should I take to ground "negative as well as positive inputs" as I fear I am misunderstanding. (this is single ended version, all puck).
Reading various members fireup encounters I dont see these items discussed.
Also, my "jumper pins" are very loose fitting. Does this not matter, or should I bend pins a touch to tighten?
Thanks,
Russellc
In the fireup instructions, it says "Ground negative input" and also says "Also ground positive input." The first time I read the thread I simply assumed it was talking about having shorting jacks in the inputs. Now that I am looking more carefully while getting ready to put into practice, it appears to be referring to something else. What steps should I take to ground "negative as well as positive inputs" as I fear I am misunderstanding. (this is single ended version, all puck).
Reading various members fireup encounters I dont see these items discussed.
Also, my "jumper pins" are very loose fitting. Does this not matter, or should I bend pins a touch to tighten?
Thanks,
Russellc
simply ground both inputs, shorting plug(s) or whatever way more convenient for you
jumper pins - mater of adequately squeezing jumper contacts ( looking from bottom side, two inner sides, take needle and push them both to outside, to be closer to outer sides)....... nothing having with pins on pcb
damn jumpers are new, ditto from zipbag; no gradation of these nor various fabs info available, so one can choose from; so - it is what it is, sometimes needing to be taken care of as written up
note - it could be wise inserting temporary fuses in rails, say 3A15, during setting procedure
maybe I'll include that in "short setting procedure" text, maybe not ..... that trick being sorta common knowledge
jumper pins - mater of adequately squeezing jumper contacts ( looking from bottom side, two inner sides, take needle and push them both to outside, to be closer to outer sides)....... nothing having with pins on pcb
damn jumpers are new, ditto from zipbag; no gradation of these nor various fabs info available, so one can choose from; so - it is what it is, sometimes needing to be taken care of as written up
note - it could be wise inserting temporary fuses in rails, say 3A15, during setting procedure
maybe I'll include that in "short setting procedure" text, maybe not ..... that trick being sorta common knowledge
you have positive input to amp pcb, connected to hot pin of RCA and pin 2 of XLR, if existing; marked as IN+ at shm and amp pcb
also negative input to amp pcb, connected to XLR pin 3, if existing, or pcb jumper filed soldered, for case of not using XLR; marked as IN- at schm and amp pcb
also input GND pad near two above, where GND RCA is connected and pin 1 of XLR, if existing; clearly marked near two above, at schematic and amp pcb
when you short positive input to input GND and negative input short to input GND, that's "inputs grounded"
sort of staring at schematic with both eyes, then shutting left eyelid, then shutting right eyelid
when bot shut, you can't see schematic, same as amp inputs can't receive anything, when shut to GND
- temporary 3A15 fuses in between amp pcb and Cap Bank, one per positive rail, one per negative rail
also negative input to amp pcb, connected to XLR pin 3, if existing, or pcb jumper filed soldered, for case of not using XLR; marked as IN- at schm and amp pcb
also input GND pad near two above, where GND RCA is connected and pin 1 of XLR, if existing; clearly marked near two above, at schematic and amp pcb
when you short positive input to input GND and negative input short to input GND, that's "inputs grounded"
sort of staring at schematic with both eyes, then shutting left eyelid, then shutting right eyelid
when bot shut, you can't see schematic, same as amp inputs can't receive anything, when shut to GND
- temporary 3A15 fuses in between amp pcb and Cap Bank, one per positive rail, one per negative rail
That little ground pad near inputs is what got me wondering. looking at other straight mosfet XA 252 builds here I dont see anything connected to this ground pad. I do not have XLR this build, only RCA.
"also input GND pad near two above, where GND RCA is connected " My RCA is connected to IN+ and IN-. Nothing to ground pad. (right now) Are you saying to add temporary jumper from IN- to this ground pad?
" when you short positive input to input GND and negative input short to input GND, that's "inputs grounded" Are you saying to add temporary jumper from IN+ to ground pad?
Or long way of saying "use shorting plugs" lol! That little ground pad is bugging me....
Russellc
"also input GND pad near two above, where GND RCA is connected " My RCA is connected to IN+ and IN-. Nothing to ground pad. (right now) Are you saying to add temporary jumper from IN- to this ground pad?
" when you short positive input to input GND and negative input short to input GND, that's "inputs grounded" Are you saying to add temporary jumper from IN+ to ground pad?
Or long way of saying "use shorting plugs" lol! That little ground pad is bugging me....
Russellc
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if you're using just input RCA, you connect IN+ pad to RCA hot, input GND pad to RCA sleeve, then you solder small SJ1 shorting field to practically short IN- to GND permanently
if you're using XLR, you connect IN+ pad to XLR pin 2, input GND pad to XLR pin 1, IN- pad to XLR pin 3
if you want to have also RCA option, connect with short tiny wires XLR pin 2 to RCA hot, XLR pin 1 to RCA Sleeve; when you want to use RCA input, you must insert "U" plug in XLR, connecting 1 and 3 contacts
temporary shorting inputs to GND , or temporary grounding inputs is nothing else than shorting them all together temporary, to prevent any possible garbage to creep in, while performing setting procedure
in other words - temporary muting inputs ............................. same as having volume pot on some input; when you dial it all the way down, wiper is practically shorted to GND; and input node is always connected to pot wiper
for all that you can use appropriate shorting plugs, you can solder tiny wires etc.
if you're using XLR, you connect IN+ pad to XLR pin 2, input GND pad to XLR pin 1, IN- pad to XLR pin 3
if you want to have also RCA option, connect with short tiny wires XLR pin 2 to RCA hot, XLR pin 1 to RCA Sleeve; when you want to use RCA input, you must insert "U" plug in XLR, connecting 1 and 3 contacts
temporary shorting inputs to GND , or temporary grounding inputs is nothing else than shorting them all together temporary, to prevent any possible garbage to creep in, while performing setting procedure
in other words - temporary muting inputs ............................. same as having volume pot on some input; when you dial it all the way down, wiper is practically shorted to GND; and input node is always connected to pot wiper
for all that you can use appropriate shorting plugs, you can solder tiny wires etc.
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I see SJ1 in schematic going to ground. So I need to add jumper between ground pad and +IN pad. Never caught this in build pics.
Is this the same thing as Aleph J? It also had option for XLR and had to use jumper, or if using XLR, small shorting piece inserted in XLR.
I didnt use XLR on that amp either! If build pics I looked at included the XLR jacks, I guess they wouldnt be using the jumper....
So, these permanent jumpers and shorting plugs. Solder in CL-60 from power supply to ground, (CL-60 to large to fit NTC pads on HA boards) and then it's to the variac....
Is this the same thing as Aleph J? It also had option for XLR and had to use jumper, or if using XLR, small shorting piece inserted in XLR.
I didnt use XLR on that amp either! If build pics I looked at included the XLR jacks, I guess they wouldnt be using the jumper....
So, these permanent jumpers and shorting plugs. Solder in CL-60 from power supply to ground, (CL-60 to large to fit NTC pads on HA boards) and then it's to the variac....
you can just ignorer SJ1, treat it as - familiar to you - Aleph J, and conduct testing procedure in same way, regarding input connection
anyhow, if you didn't short inputs to GND while setting Aleph J, you wasn't advised well;
it is not necessary only when Big Boys are working ........ Papa for instance
we Boyz need any available help and trick to not bugger it all
anyhow, if you didn't short inputs to GND while setting Aleph J, you wasn't advised well;
it is not necessary only when Big Boys are working ........ Papa for instance
we Boyz need any available help and trick to not bugger it all
About a month ago I posted that my take on the XA252 was cooking in and the next step was to do some testing before playing music on my test speakers. DC operation was working fine so it was time for a 1kHz AC test. At the time for what ever reason I was not getting any voltage gain and decided to start looking at components on the board. Everything I checked was OK so I decided to check the other channel and found the same situation. To make a long story short I spent some quality time with the schematic and my boards and found that I had installed a 100 Ω resistor for R 16 (feedback resistor) instead of 100kΩ (on both boards!). No error to the LTP no voltage gain.
Now everything is hunky-dory with great foot tapping sound stage on my test speakers.
I do get an almost immediate minor thump on power up. On power down also but with some time delay (when the LEDs go dark). I need to check into this before trying the amp on my lounge system.
One other irritating thing is that the power supply was dead silent (no hum locally or from the LS) until I moved the amp to another location. Now I get a hum locally. Will also look into this.
A huge thanks to ZM.
Now everything is hunky-dory with great foot tapping sound stage on my test speakers.
I do get an almost immediate minor thump on power up. On power down also but with some time delay (when the LEDs go dark). I need to check into this before trying the amp on my lounge system.
One other irritating thing is that the power supply was dead silent (no hum locally or from the LS) until I moved the amp to another location. Now I get a hum locally. Will also look into this.
A huge thanks to ZM.
when arranging it for SE- RCA signal in
only while conducting setting procedure
later you bring signal to amp, RCA or XLR, your choice
that depends of nature of your PSU - mild thump or no thump at all
if worry, remove JP1 jumper for good, should be thumpless