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5k:8 ohm vs. 10k:16 ohm output transformer. What is the difference?

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Assuming that they're designed for the same (low end) frequency response and power level, the 10K:16 Ohm would need twice the inductance - more primary and secondary turns on the same core. This would probably require dropping the wire size, so might end up with twice the DC resistance. Loss would be similar to the 5K:8 Ohm at rated impedance. High end would likely suffer due to double effect of higher winding capacitance and higher impedance source.
 
It all depends on which tradeoffs the transformer maker chose to make. As the primary circuit impedance is increased there is a tradeoff of Lpri vs distributed capacitance. More turns are needed in general. It can go either way, to the high end or the low end or both. DC resistance will of course increase but if it's in proportion to the Zpri it's OK. The thing to look for in a high performance high Zpri OPT is more sectioning of the winding.
 
Can you back that up with data? They might be the same, note that the 10k:16 quotes a primary DCR and a primary inductance, while the 5K:8 does not. That is the data that would prove they are the same.

Let me try one more time.

You want me to provide data that is not provided by Edcor?
The stated input and output impedances indirectly tell us the turns ratio of the windings. They are the same for both transformers.

From the data provided we do not know how the transformers are built; or the AWG of the windings, primary inductance, blah, blah and blah.

There very well may be something Edcor is not telling in the provided data sheets.

DT
 
DualTriode said:
They are the same for both transformers.
Maybe I am just dumb, but I thought that was the point of this thread? Given the same winding ratio, what else might be different - some possibilities have been given, such as winding resistance, capacitance, DC saturation. Now it is possible that the two transformers are identical, but unlikely as that just multiplies part numbers for no good reason.
 
A quick look and the stat that gives me pause is that the frequency response of both is the same even though the windings are quite different. This would assume that distributed capacitance, leakage inductance etc are the same in both. Imo, not likely.

However, the FR figures could be conservative approximations.

Cheers.
 
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ehh, I thought it was common 'practice' to raise or lower primary 'plate load' by changing speaker connection on secondary

which means that if your 16ohm speaker is a more 'ordinary' 12ohm, then the secondary....
or if you 8ohm speaker is more likely to be 6ohm, then.........
or what ?
 
That would indeed be the whole point. If Edcor was indeed making only 1 item and identifying 2 applications for it as a marketing ploy, they naturally would write a conservative spec that would be achieved in both applications.

Yep, I agree. Also notice the price is exactly the same. If the trannies were different, winding time would be different and reflected in the price, unless one is more profitable than the other.
Also notice the primary inductance is only 25 henries, not really enough to justify the spec with 10k primary imo.

Cheers.
 
Hello,

Edcor my know more than they are telling.

You are right being plexed. The impedance ratios are the same for both transformers.

From the data given they are the same.

DT

Mate...just above you have four guys explaining they are NOT the same, why you mess it up? We all agree the ratios are the same, but the transformers cannot be if the bandwidth is to be the same, all explained by the posts above yours...

Regarding price being the same, Edcor have all transformers in the same series using the same core costing the same. I guess they just figured it easiest that way instead of having to calculate the minute difference the cost of 1000 turns vs 1200turns will be.
 
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