Signal transformers made according Deutsche Post specifications via Pflichtheft so very stringent high quality requirements.
I have F&G, Sedlbauer and a few other brands. Pairs are of course both the same brand and year of manufacture (most are made in 1985).
All measure equally well. They are flat from 20 Hz to 20 kHz. They weigh 970 gram a piece. When you are used to Aliexpress stuff these are something else with 0.00xx% distortion at 2 Vrms in the whole audio band. They can be used 2:1, 1:1 and 1:2. They are 80 x 90 x 40 mm. Please note that they have all the mechanical and electrical items one likes to have like shielded casing, static screen and incredibly good performance. Maximum voltage is 60V 😀 Sound quality simply is excellent.
I think 150 Euro a pair ex shipping within mainland Europe is a fair price. They won’t be shipped to any destination outside Europe.
I have F&G, Sedlbauer and a few other brands. Pairs are of course both the same brand and year of manufacture (most are made in 1985).
All measure equally well. They are flat from 20 Hz to 20 kHz. They weigh 970 gram a piece. When you are used to Aliexpress stuff these are something else with 0.00xx% distortion at 2 Vrms in the whole audio band. They can be used 2:1, 1:1 and 1:2. They are 80 x 90 x 40 mm. Please note that they have all the mechanical and electrical items one likes to have like shielded casing, static screen and incredibly good performance. Maximum voltage is 60V 😀 Sound quality simply is excellent.
I think 150 Euro a pair ex shipping within mainland Europe is a fair price. They won’t be shipped to any destination outside Europe.
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Yes I have a few pairs. Same brand, series and date codes. All measure the same BTW. Please contact me via PM.
I got two of these transformers from Jean Paul and all I can say is wow.
Been transformer coupling since many years these are the best sounding transformers I tried so far.
Get a Ustars dual mono AK4493 Dac for €70 remove the opamps and put these trannies on the corresponding socket and you got a fantastic sounding Dac.
See my test setup with MA12070 amp module:
Been transformer coupling since many years these are the best sounding transformers I tried so far.
Get a Ustars dual mono AK4493 Dac for €70 remove the opamps and put these trannies on the corresponding socket and you got a fantastic sounding Dac.
See my test setup with MA12070 amp module:
Mmmmm that has changed to 6 pairs left 🙂 I will ship to the UK (of course) but please note that shipping to the UK is 27 Euro nowadays.
OK, I shipped a few pairs. If you are looking for extreme good performance for a reasonable price there are a few pairs left. Most by F&G and Sedlbauer.
Some tips:
- always mount these with the M4 bolts and preferably vertically. These were meant to be mounted and leaving them loose will result in damage when something goes wrong.
- Never measure their windings/resistance with a DMM.
- check DC offset as signal transformers don't like DC. A few mV are no issue.
Some tips:
- always mount these with the M4 bolts and preferably vertically. These were meant to be mounted and leaving them loose will result in damage when something goes wrong.
- Never measure their windings/resistance with a DMM.
- check DC offset as signal transformers don't like DC. A few mV are no issue.
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In a strange coincidence I got hold of "new in box" pairs of these which I bought all. So unused and unsoldered in their original boxes. Mostly 1985 production by various German brands produced for Deutsche Post (all measure the same) in pairs with equal date code and by the same brand so no "unequal" pairs.
Original boxes so well protected against transport damage. Send me a PM if you are interested. EU only!
Original boxes so well protected against transport damage. Send me a PM if you are interested. EU only!
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Did the original boxes come with any additional goodies such as spec sheets or graphs or anything?
Don’t worry like I did about the 3.4 kHz Sedlbauer states as they have way higher bandwidth.
The 325 is not in the list AFAIK but I have its rudimentary spec sheet but does not contain connection diagrams. The ones by other brands are also without datasheet probably as these were for Deutsche Post.
The 325 is not in the list AFAIK but I have its rudimentary spec sheet but does not contain connection diagrams. The ones by other brands are also without datasheet probably as these were for Deutsche Post.
Apparently you did some own measurements. Could you please post these?