Hi Dario,
I powered my first module a few hours ago and it plays music really good. I'm using a 15Vac transfo which I measured to be about 16.5Vac unloaded. All measure points are fine except the -35Vdc and + 35Vdc where I get 21Vdc. I know this is due to my input voltage but I will be having a 4 Ohms load.
The relay won't click but I'm getting only 10Vdc reading on the coil, so I connected my speaker gnd to PGND in the meantime.
Let me know if you have any pointers. So far it seems to be playing really good but I need to let components settle in.
The only thing is that it seems to clip really fast. Should I be using a 22Vac secondaries for 4Ohms load instead of the 15Vac?
Thanks
Do
BTW, the RelCap I bought for C30 fits really nicely in position. You need to gently bend the leads since the spacing is not the same but it is all nice.
I powered my first module a few hours ago and it plays music really good. I'm using a 15Vac transfo which I measured to be about 16.5Vac unloaded. All measure points are fine except the -35Vdc and + 35Vdc where I get 21Vdc. I know this is due to my input voltage but I will be having a 4 Ohms load.
The relay won't click but I'm getting only 10Vdc reading on the coil, so I connected my speaker gnd to PGND in the meantime.
Let me know if you have any pointers. So far it seems to be playing really good but I need to let components settle in.
The only thing is that it seems to clip really fast. Should I be using a 22Vac secondaries for 4Ohms load instead of the 15Vac?
Thanks
Do
BTW, the RelCap I bought for C30 fits really nicely in position. You need to gently bend the leads since the spacing is not the same but it is all nice.
Wow, a lot to answer to...
Cables cost a lot... and two years ago I've tried some of the chinese clones, some low price (!) Furutechs and Suburra's made OCC aluminum cables.
My favourites are currently Suburra's ones.
I've still to try Acrolink ones, they should be the second best.
If you can find it a real bargain is the XLO Reference 2 clone (see aliexpress or dhgate)
Disclaimer:
We're talking about the last 2% of performance, how much you value such tiny differences is highly subjective.
IMHO every cable sound different, also power AC ones but it's strongly dependant on PS topology and quality.
A well designed regulated PS reduces a lot AC cable contribution.
In fact the original My_Ref performance was much more dependant on AC cable quality than the FE but you can still hear differences.
My Sony SACD player's strongly regulated PS seems not so sensitive (if any) to AC cables.
Chinese eBay seller have a 'creative' way to represent their products and materials they're made of...
BTW not all those parts are bad...
CMC connectors are excellent
XLO Reference 2 clones are excellent
Sonar IEC plugs are excellent (real copper)
On contrast Sonar Shuko plugs are made of brass (declared as copper), they still sound good tough.
For sure none of the Sonar plugs are cryoed...
BTW that IEC inlet was not exactly cheap... I've paid it 10€ vs 17€ of Furutech FI-03...
I mostly agree but don't overlook cables, though.
Interesting.
You see, I'm searching an alternative to TCs for two reasons:
I'm curious too...
I'm using plain stranded H07V 2 sq mm mains cable with great results.
All those parts could make a (tiny) difference.
Fine
15V are WAY too low, you should use 21V secondaries
Obviously, with such low voltage secondaries...
Guess what?
A suggestion...think 21...
Absolutely... 21V
Cables cost a lot... and two years ago I've tried some of the chinese clones, some low price (!) Furutechs and Suburra's made OCC aluminum cables.
My favourites are currently Suburra's ones.
I've still to try Acrolink ones, they should be the second best.
If you can find it a real bargain is the XLO Reference 2 clone (see aliexpress or dhgate)
Disclaimer:
We're talking about the last 2% of performance, how much you value such tiny differences is highly subjective.
IMHO every cable sound different, also power AC ones but it's strongly dependant on PS topology and quality.
A well designed regulated PS reduces a lot AC cable contribution.
In fact the original My_Ref performance was much more dependant on AC cable quality than the FE but you can still hear differences.
My Sony SACD player's strongly regulated PS seems not so sensitive (if any) to AC cables.
Chinese eBay seller have a 'creative' way to represent their products and materials they're made of...
BTW not all those parts are bad...
CMC connectors are excellent
XLO Reference 2 clones are excellent
Sonar IEC plugs are excellent (real copper)
On contrast Sonar Shuko plugs are made of brass (declared as copper), they still sound good tough.
For sure none of the Sonar plugs are cryoed...
BTW that IEC inlet was not exactly cheap... I've paid it 10€ vs 17€ of Furutech FI-03...
I mostly agree but don't overlook cables, though.
Interesting.
You see, I'm searching an alternative to TCs for two reasons:
- I want a cap that could be fitted on boards and new TCs can't
- new TCs are as musical and detailed as old ones but not as neutral/transparent, they add some 'amber' to the sound.
I'm curious too...
I'm using plain stranded H07V 2 sq mm mains cable with great results.
Don't know if using something like a gold plated set would make a difference in the mains path. It seems to me that unless one insures that the metal used in a mains switch and the fuse (even if part of a quality AC inlet) are carefully selected, there is still a fly in the buttermilk.
All those parts could make a (tiny) difference.
Fine
15V are WAY too low, you should use 21V secondariesObviously, with such low voltage secondaries...
Guess what?
A suggestion...think 21...
Absolutely... 21V
Something in my head keeps telling me to buy a 21Vac transfo
I agree, 21 VAC secondaries are a good choice for 4 Ohm speakers. I am also fine using 22 VAC secondaries with 4 Ohm speakers. Mine are Antek torroids, good prices and quality from New York. I suspect you will find what you want in Canada, since there are a lot of good suppliers there, but here is the Antek link, just in case.
http://www.antekinc.com/
By the way, I noticed your list of amps in your signature. COOL! I will be interested in hearing your opinions on the FE. I'm also curious about the Telos 390 Clone. How do you like it?
Jac
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Something in my head keeps telling me to buy a 21Vac transfo
I'm using 22VAC single transformer with 4 Ohm speakers and it's ok
ps. for Dario: 9mV and 7.5mV are the DC values on outputs with open in (after less than 2 hours total working)
Spin,
check your output offset with the input shorted to signal ground, then with your Source connected. and with the volume control at various settings.
The output offset is likely to vary at least a little, but what you MUST ensure is finding any combination of possible operation modes that give an unexpected BIG change in output offset.
check your output offset with the input shorted to signal ground, then with your Source connected. and with the volume control at various settings.
The output offset is likely to vary at least a little, but what you MUST ensure is finding any combination of possible operation modes that give an unexpected BIG change in output offset.
Now My_Ref FE is on the cassis and playing music with RCA cable soldered directly to the fresh stereo pot. I must say it is impressive to say the least! The sound is so natural, the instruments sound absolutely real. Ofcourse after some time the brain will burn in and I'll see possibilities for improvement (at the moment it is just industrial BOM), but now I am absolutely dazzled by the result! And it was so simple to get there. But that is because someone has produced this simplicity for us with his natural talent and hours and hours of work
Hi Jac,
Yeah, I bought several transfos from Antek through the years but starting to use more and more SumR since they are local and make amazing products. I can request any custom transfos. For the My_ref I just asked for a quote on 4x secondary @ 21Vac. So just using one transfo but still dual mono.
Send me a PM about the Telos 390 clone since I do not want to pollute Dario's thread.
Thanks
Do
I'm jealous 
Those R-Cores look sooo appealing. From here it looks like you could turn the TCs 90 degrees and shorten the leads. No?
To settle my mind, I went to my electric service box to see which color wire did what. I try keep those same assignments color throughout the entire amp. If there are different colors in some components, I put a small piece of the correct color heat shrink tubing near the ends of each wire.
Those R-Cores look sooo appealing. From here it looks like you could turn the TCs 90 degrees and shorten the leads. No?To settle my mind, I went to my electric service box to see which color wire did what. I try keep those same assignments color throughout the entire amp. If there are different colors in some components, I put a small piece of the correct color heat shrink tubing near the ends of each wire.
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