appropriate/better filtering, being adjusted to actual power draw
or, which is most certain, less costly - higher draw asking for stronger everything, so smaller one hopefully being cheaper
anyhow- you don't need filter declared for more than 1A
They are cheapest from Mouser (using Octopart search), but all the flavors are within a few cents of each other. Go figure.
It smelled but, I just chalked it up to transformer heat. No smoke though. Burnt spots easily hidden by heatsink.
My guess is the long legged caps shorted on case bottom which is attached to ground. Fused switch dug up from parts bin new parts ordered
I thought this info might save some folks a little time. Per the spec sheet, these do not include fuse drawers!
Schurter 1A power module with both poles fused: DD12.1121.111
Schurter 1A power module with single pole fused: DD12.1111.111
Fuse Drawer (dual pole): 4301.1401 or 431.1403
Fuse Drawer (single pole): 4301.1405 or 4301.1407
Schurter 1A power module with both poles fused: DD12.1121.111
Schurter 1A power module with single pole fused: DD12.1111.111
Fuse Drawer (dual pole): 4301.1401 or 431.1403
Fuse Drawer (single pole): 4301.1405 or 4301.1407
My case made it from Italy to TX in 96 hours!
Hopefully here by Monday. Excied to hear the truth machine sing.
🙂
Hopefully here by Monday. Excied to hear the truth machine sing.
🙂
It occured to me that, after the M2X, I dont know what other amps I'll be able to use the 2V/V gain with. My sources will give 4 or 8v out, single and balanced. I know the F4 is out of the picture but I already have a never-to-be-replicated-again collection of glass bottles for pre projects to feed that. Unfortunate they're so expensive now.
Will the Iron Pre balanced be sufficient for the 2Sk180 and TH-51 amps being born? Seems many of the vfet/sit amps dont need a whole lot of preamp, already making sufficient gain on their own. And I dont want to stack THD on THD by putting a harmonically dense preamp infront of one of those when the day comes.
I know one could direct me to learn to calulate input sensitivity for those, but I'm not there yet and acutely aware of the fact I'll need a period of study before even attempting to build one.
Will the Iron Pre balanced be sufficient for the 2Sk180 and TH-51 amps being born? Seems many of the vfet/sit amps dont need a whole lot of preamp, already making sufficient gain on their own. And I dont want to stack THD on THD by putting a harmonically dense preamp infront of one of those when the day comes.
I know one could direct me to learn to calulate input sensitivity for those, but I'm not there yet and acutely aware of the fact I'll need a period of study before even attempting to build one.
Iron Pre is sufficient, when speaking of SIT amps (of Mighty Provenance):
SissySIT
Singing Bush
Choked Singing Bush ( even if that one mostly existing in Realm of Ideals)
Babelfish XA252 SIT
practically - any SIT amp not being a follower is well driven with Iron Pre
and , if one having sensitive and efficient spks, with decent sources, Iron Pre can drive followers to foot-tapping levels
wanna calc for followers?
Vrms of source, multiply with Iron Pre V/V gain, you get final Vrms
power is (Vrms^2)/Rload
SissySIT
Singing Bush
Choked Singing Bush ( even if that one mostly existing in Realm of Ideals)
Babelfish XA252 SIT
practically - any SIT amp not being a follower is well driven with Iron Pre
and , if one having sensitive and efficient spks, with decent sources, Iron Pre can drive followers to foot-tapping levels
wanna calc for followers?
Vrms of source, multiply with Iron Pre V/V gain, you get final Vrms
power is (Vrms^2)/Rload
Perfect, thank you.
Speakers in the house now are 90 and 93db. All future will be above 90, only question is how far. Spousal permission for one more set has been attained....and this has led to much trepidation. To horn or not to horn? So many choices in the DIY domain, hard to decide. I almost sprang for a Troels Gravesen 3WC-10 but have been having second thoughts.
Also, seems the amps I love most tend to be a little squishy in the low end.
I need a t-shirt that says Ohm is everywhere!
Speakers in the house now are 90 and 93db. All future will be above 90, only question is how far. Spousal permission for one more set has been attained....and this has led to much trepidation. To horn or not to horn? So many choices in the DIY domain, hard to decide. I almost sprang for a Troels Gravesen 3WC-10 but have been having second thoughts.
Also, seems the amps I love most tend to be a little squishy in the low end.
I need a t-shirt that says Ohm is everywhere!
It's a matter of preference, but I much prefer soldering the wiring to the jacks before installing the jacks. I install them from the 'inside'. To me, it looks a little cleaner. Most important (to me) is that it's much easier for me to keep the input/output wiring shorter / tidier and easier to install without trying to manage the back panel.
My Iron Pre SE is ready now: I listened to it yesterday night for a few hours, and I must say, I'm really delighted about it.
The Iron Pre sound very natural and airy: wood and brass instruments sound very natural, as well as piano; voices are phenomenal! Even electronic sounds are clean and pleasant.
I listened to tunes from Joscho Stefan, Patricia Barber, Philip Catherine, John McLaughlin, Johnny Cash, Terje Rypdal, Malia, Rodolphe Burger, The Clash, Pink Floyd. All different kind of ensembles, recoding techniques. In all cases, Iron Pre was perfect!
I had connected the Iron Pre to a Quad 306 power amplifier, connected itself to a pair of Davis Balthus 50 speakers. On input side, I had connected a Philips CD-Player and a (DIY) streamer (in the Quad FM2 case). All connected to a mains filter. It replaced my Quad 66 preamp, which I usually use for my office stereo set.
I mounted the RCA socket on a black nylon panel which I had lying around.
As it's a DIY project, I welded a trafo case from sheet metal, placed the trafo into it and filled the whole thing with epoxy (don't ask what a mess that was...). Finally, the trafo is screwed from the bottom with a nylon screw (I found some in my parent's house - I guess from swimming pool stuff).
Thanks a lot to you Zen Mod, and to all the contributors and last, but not least, to the gentlemen running the DIYaudio store.
Now I need to build an adequate power amp: Q17 turbo and Alpha Nirvana and are waiting for completion...
The Iron Pre sound very natural and airy: wood and brass instruments sound very natural, as well as piano; voices are phenomenal! Even electronic sounds are clean and pleasant.
I listened to tunes from Joscho Stefan, Patricia Barber, Philip Catherine, John McLaughlin, Johnny Cash, Terje Rypdal, Malia, Rodolphe Burger, The Clash, Pink Floyd. All different kind of ensembles, recoding techniques. In all cases, Iron Pre was perfect!
I had connected the Iron Pre to a Quad 306 power amplifier, connected itself to a pair of Davis Balthus 50 speakers. On input side, I had connected a Philips CD-Player and a (DIY) streamer (in the Quad FM2 case). All connected to a mains filter. It replaced my Quad 66 preamp, which I usually use for my office stereo set.
I mounted the RCA socket on a black nylon panel which I had lying around.
As it's a DIY project, I welded a trafo case from sheet metal, placed the trafo into it and filled the whole thing with epoxy (don't ask what a mess that was...). Finally, the trafo is screwed from the bottom with a nylon screw (I found some in my parent's house - I guess from swimming pool stuff).
Thanks a lot to you Zen Mod, and to all the contributors and last, but not least, to the gentlemen running the DIYaudio store.
Now I need to build an adequate power amp: Q17 turbo and Alpha Nirvana and are waiting for completion...
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- not nearly enough porn
- signal wires (twisted pairs) still too fat
- for butchering FM3, you owe to buy another one (functional) and put it to permanent use, hoping that Swiss is still having available some cultural FM program active; believe it or not, proper FM is still better than majority of web based broadcasting
- take care to keep enough distance between Iron Pre and any nasty behaving mains xformer around
The FM2 wasn't really working anymore; I recycled the case to fit a Quad 33 pre and 405 power amp.
I seldomly listen to radio: I hate the penetrant ads all few minutes. I ripped all my CDs a few years ago and have them all on a NAS. The CD player is used only when I have new CDs not yet on the NAS. I even don't stream from the internet. Probably I'm somewhat old school...
Thanks for the hint with the signal wires: I took what I had at hand.
Do you really think it's an issue? I even welded them on connector pins in order to allow for removal without deteriorating the PCB.
I seldomly listen to radio: I hate the penetrant ads all few minutes. I ripped all my CDs a few years ago and have them all on a NAS. The CD player is used only when I have new CDs not yet on the NAS. I even don't stream from the internet. Probably I'm somewhat old school...
Thanks for the hint with the signal wires: I took what I had at hand.
Do you really think it's an issue? I even welded them on connector pins in order to allow for removal without deteriorating the PCB.
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It's cool to see more of these getting built with all the variations.
I had made the decision to use a chassis I had on hand, and having done a lot of machining of the front and rear panels, decided to use it rather than buy the excellent project-specific one.
After a few hours of use I noticed the chassis getting warm, so I popped off the lid and measured the temperatures; the IRF parts were getting up to 95F, so I decided to install small heat sinks onto those parts (all other TO-220s had them already), and cut holes in the top and bottom lids for some round vent caps. Having a milling machine and proper carbide hole cutters exactly the correct size was a major incentive.
The entire unit is running cooler now, though I might increase the size of the heat sinks on M1 and M2 later.
Confirming again how much I enjoy the sound of this preamp! There is great dynamic range and clarity - really lovely preamp.
I had made the decision to use a chassis I had on hand, and having done a lot of machining of the front and rear panels, decided to use it rather than buy the excellent project-specific one.
After a few hours of use I noticed the chassis getting warm, so I popped off the lid and measured the temperatures; the IRF parts were getting up to 95F, so I decided to install small heat sinks onto those parts (all other TO-220s had them already), and cut holes in the top and bottom lids for some round vent caps. Having a milling machine and proper carbide hole cutters exactly the correct size was a major incentive.
The entire unit is running cooler now, though I might increase the size of the heat sinks on M1 and M2 later.
Confirming again how much I enjoy the sound of this preamp! There is great dynamic range and clarity - really lovely preamp.
not an issue at all
just my OCD having tiniest possible wires for signal
additional contacts - well, I wouldn't do that, but if you like it ....... again, matter of principle
one by one detail - not that much each one per se, but amass them several and suddenly there is a difference, in sound and sometimes even in longevity of actual build