Hi All,
The power trafo has died in my DAC. Could someone please advise where I can find a replacement? Metrum Acoustics are not responding to emails and my tech tells me he cannot source one that will fit inside the case.
230v in - - 2 x 10v out @ 0.75A
Max 22mm high to fit inside the very slim case.
Thank you,
Dave
The power trafo has died in my DAC. Could someone please advise where I can find a replacement? Metrum Acoustics are not responding to emails and my tech tells me he cannot source one that will fit inside the case.
230v in - - 2 x 10v out @ 0.75A
Max 22mm high to fit inside the very slim case.
Thank you,
Dave
Flat transformers at the VA you require are over 22mm high.
Tried 10 manufacturers ,10VA seems to be the highest that keep it at or under what you need
Tried 10 manufacturers ,10VA seems to be the highest that keep it at or under what you need
Interestingly, I had the exact same failure of my Octave a couple of months ago.
No,I did not find a replacement for the (probably) custom made low profile Amplimo transformer, however, I found that a 2 x 9 V / 0.65 A transformer is more than capable of powering the Octave. Makes you wonder why they went for a 15 VA...
No,I did not find a replacement for the (probably) custom made low profile Amplimo transformer, however, I found that a 2 x 9 V / 0.65 A transformer is more than capable of powering the Octave. Makes you wonder why they went for a 15 VA...
What died? The primary winding? They are not that far from me, if you like I can ask for the original replacement.
Possibly yes. It blew the T100mA primary fuse one day which I replaced. It worked for a couple of months and then it blew the fuse again, for good this time. From that moment on, the transformer would draw 1.6 A from the primary if I bridged the fuse with an ammeter (no load connected).
The PSU and DAC sections were fine, I powered them from a lab supply and there were no problems. I experimented with voltages and measured currents and found that the 2x 10 Vac/0.75 A transformer seemed a bit of overkill to me. A 2x 9 Vac would still have way more voltage output needed to feed the linear regulators above their dropout voltages.
I unwound the entire transformer expecting to find something, but alas.
I will post some pictures later today.
The PSU and DAC sections were fine, I powered them from a lab supply and there were no problems. I experimented with voltages and measured currents and found that the 2x 10 Vac/0.75 A transformer seemed a bit of overkill to me. A 2x 9 Vac would still have way more voltage output needed to feed the linear regulators above their dropout voltages.
I unwound the entire transformer expecting to find something, but alas.
I will post some pictures later today.
Hi, what linear regulators are used? What is their output voltage and what is the required input voltage? I don't know the device but maybe you can even use a 2 x 7V one?
Sometimes transformers just die prematurely. I once got an amount of German made EI PCB mount transformers for free from an audio manufacturer as their primary winding supposedly got interrupted after time. These did not become warm or something like that. The tale that I did not believe (thinking it was the circuit) turned out to be true.
BTW 22 mm is non standard and also very thin for a 15VA type.
Sometimes transformers just die prematurely. I once got an amount of German made EI PCB mount transformers for free from an audio manufacturer as their primary winding supposedly got interrupted after time. These did not become warm or something like that. The tale that I did not believe (thinking it was the circuit) turned out to be true.
BTW 22 mm is non standard and also very thin for a 15VA type.
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So, I had to dig up my old pictures of the Octave I took when I had just bought it in 2012.
The transformer is a low profile Amplimo XN1798P. The linear regulators are jelly bean fixed 3.3 V and 5 V types and LM317/337 (also set to +/- 5 V) for the DACs. 15 VA is overkill, and as you can see there used to be a 7 VA option (which at the time was not offered).
The transformer is a low profile Amplimo XN1798P. The linear regulators are jelly bean fixed 3.3 V and 5 V types and LM317/337 (also set to +/- 5 V) for the DACs. 15 VA is overkill, and as you can see there used to be a 7 VA option (which at the time was not offered).
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Mmm, I am somewhat more cautious. I think the 7VA option was intended for another Metrum DAC type which I owned but I forgot the type number/name (it was not very impressive).
Amplimo XN1798P is indeed a custom wound type.
Amplimo XN1798P is indeed a custom wound type.
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Now, my solution was not very elegant, but effective. It cost me a whopping € 5 and a bicycle trip to get a second hand 2 x 9 V 0.65 A transformer including a sturdy plastic case. I mounted this inside the existing case and added a switch to the front.
It's an oldie (specced at a primary voltage of 220 V instead of 230 V really dates this thing), but it works just fine.
It's an oldie (specced at a primary voltage of 220 V instead of 230 V really dates this thing), but it works just fine.
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Yes, I seem to remember there was a version with fewer DACs. 'Quad' maybe? Edit: yes the Quad.
Maybe, sounds familiar. Same casing but another motherboard. These devices were hyped up big time then with the gadget "industrial DAC chips". However my Subbu DAC completely unexpectedly turned out to be better than the 5x more expensive Metrum Quad so it was sold.
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2 x 7VA in parallel I think. Those casings were intentionally chosen small/low and then system choices need to be made.
With respect to totally unexpected qualities, I recently bough a Sony CDP-XE570 CD-player from a thrift store for € 25 (missing its remore control). I didn't expect too much from it, but I was very pleasently surprised by the sound quality from the analog outputs. It can match the way more expensive stuff I've had for over a decade.
CXD2587Q, a 1 bit outsider 🙂 I take your word for it. Do you have any recent AKM based device to compare with?