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Capability of Sony/Tamradio SE Output Transformers

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#41
mctavish said:
There is no tapped secondary... the 8 ohm and 600 ohm secondaries are separate. I havw had 10 or so pairs of these go through my hands over the years and I can say that they sound great within their limitations. Of course a modern trafo with modern materiels will walk all over them....

If you dont expect much bass they do well with a trioded 6V6 or EL84. I have a headphone amp with them and it is quite good.
Click to expand...

It doesn't really change much if tapped or not. The point is that if secondary turns are not all actively used FR will be worse. The more turns are left unused the worse. So leaving the 600R unused is the worst case.

The problem is not the bass but the trebles...
 
#42
TG said:
The Sony TC-500A manual specifies 30Hz-18kHz (at unknown rolloff) at line output, which is fed exactly with this 600 Ohm secondary. Might be with gNFB though, I haven't looked at the schematics very carefully.
Click to expand...

No feedback I think but the FR in the specs I would assume is the one of the entire tape recorder which is heavily dependent on the tape head. It might be better for use as line preamp only.
 
#43
Akai M8 XFRM'r next to Sony TC500A
Akai corroded , Sony very clean
Then some Nickel %60 PB I have for comparison
 

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#44
0-1.jpgI dismantled a damaged Sony Tamradio Transformer , the laminations are soft and shiny .
They are easily bent and twisted and are most likely Permalloy, they are not Silicon Steel.
Some are copper coated in colour, the wax melted and on closer inspection now ,may have caused a film to build up.
 
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#46
Now the faulty core is dismantled and cut down on the Sony Tamradio 5K output transformer it looks to be 3Px2S for the 8 ohm tap ( not bifilar ) but the 600ohm appears to be mutlifilar on the outer windings only.
The windings are very neat and tidy , but the lack of miltifilar on the 8 ohm secondary 2 /S partitioned account for the HF cut off at 18kHz.
The rest of the core is white / shiny easy to twist by hand would account for the lovely sound of these little transformers looking to have Nickel Laminations .
 

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#47
Recycled Sony CT500A parts

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17.jpgI decided to build a system with the stripped down Sony TC-500A .

The Amplifier is a Single Ended EL84 Running in Pentode 5 watts .
LM317 on the EL84 Cathode , 22v Zenner diode on the control grid of the EL84 and a 6J5 driver tube biased to 5.5mA 2.3V.
Parts were high quality Dale Wire Wound , Kiwame Cabon Resistors , Caddock Thick Film Resistors and Kimber Hook up wire .
The Power supply has a EZ81 Rectifier tube and all Film Power Supply Capacitors from Mouser and a low noise toroidal power transformer
https://au.mouser.com/datasheet/2/88/PPA_series-553039.pdf
http://www.humblehomemadehifi.com/download/Humble Homemade Hifi_Solo-103.pdf
The Sony Holey Basket FE103A Alnico's are installed in copies of Humble HiFi Solo 103 Cabinets .
Symmetrical loaded reflex cabinet .
The Sony SE103A are Alnico so better than the standard FE103 IMHO .
The Permalloy Vintage Tamradio Output transformers sound very nice indeed so lifelike .

The Speaker Terminals and RCA's are KLE Low Mass Copper with an Audionote Volume control dual input .

The Sound of this inexpensive build is excellent and very revealing .
Small Ensamble's Jazz and Vocals are very realistic indeed and prefer the EL84 to the Audion 300B also pictured as being more lifelike in voice reproduction IMHO .

Bass is not that deep or extended and a sub woofer would be required .
Will post the circuit for the input transformer transfer signal path for a subwoofer feed, dual volume control , one for the sub one for the Amplifier .

The Chassis is a small Alloy Hammond 200x300mm later etched decals and black anodized finish done locally in Australia .
The EL84 are AWA Miniwatt as is the EZ81 made in Australia and easily a match for NOS Mullards in quality and sound.
 

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#49
Sony FE 103A Holey Basket Baffle Step

0-1 copy.jpgHi, here is an image of the baffle step described in the Humble HiFi Solo 103 .

Supposed to even out the upper mid energy , for me i did not think that was too much of an issue .

So not convinced it is required .

Smooths the mids out a little bit takes away some detail .

Each person would need to make up their minds about that one .

Got the parts of the partsconnexion Canada, the Solen inductor is not to expensive, some prices are a little crazy for inductors.
 
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#50
Perfectusaudio said:
These transcendar 5W/5K look very good and not expensive

Transcendar Transformers - 5 Watt SE
Click to expand...

Sadly, it appears that Transcendar is no longer making transformers. I have a few that I love and I wanted another pair. I emailed them twice, first time they said they are swamped with too many orders the next time no response at all. I’d love to be wrong on this but he has gone out of business once before.
 
#54
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