OT:What going to happen if I match 200ohm amp to 16ohm speak

[sanhanul]

Actually this might be a good option, and will match just about anything. United Transformer Corp. are very high quality Transformers IMHO.

UTC LS-33 Audio High Level Line Matching Transformer | eBay

Here is another....

UTC LS-33 Audio High Level Line Matching Transformer | eBay

Thank you AB. I think this is the right trans for my amplifier. But it looks huge and I don't know how high the price will go up. I will keep that in mind anyway.

[Altec Best]

Thank you AB. I think this is the right trans for my amplifier. But it looks huge and I don't know how high the price will go up. I will keep that in mind anyway.

Your Welcome ! They are at $42 and $40 right now.But reserve not met.I think they should sell for around $50-$100.They are not too far from me. Half hour drive.... They are high quality transformers (LS-33).The seller ships to Europe.

Here are a couple of threads on the UTC Transformers at DIY Audio.

http://www.diyaudio.com/forums/tubes...c-ls-33-a.html

Passive preamp with utc transformers - diyAudio

Using the UTC LS-33 as a Push-Pull output for 2A3's - diyAudio

Here is a UTC 1960-1961 catalog. Untitled Normal Page

Data Sheet - http://www.bunkerofdoom.com/xfm/UTC_1970_WEB/023.jpg

@gvasale in post # 17 it says 18.35 watts output into 200 ohms from the google translation.

[gvasale]

Just for fun, I dug out my 1970 Cramer catalog. Lots & lots of transformers then. Triad s149a, 3k ohm ct primary, 4, 8, 16 ohm secondarys. UTC HA 135 3k/5k plate, fro 30 to 1.2 ohms in 8 steps. Also Stancor too. Try finding that stuff today. But there is a company that does custom transformers out there. Cant remember the name though.

[Steve Schell]

I don't know about this particular equipment, but many old theatre systems sent the audio signal from the projection booth to the speakers behind the screen at a high impedance to minimize losses in the wires over the long distance. Amplifier power was precious and expensive in the early days. The RCA systems routinely used a 250 ohm tap on the amplifier's output transformer, a passive two way crossover in the rack at 250 ohms, 250 ohm h.f. and l.f. lines out to the speakers, then then autoformers for both h.f. and l.f. set for the particular combination of drivers used in the system. Autoformers like these were used:

http://www.oswaldsmillaudio.com/imag...s/DSC_0691.jpg

[stéphane Rame]

RCA 9472-A specs

http://2.bp.blogspot.com/-wMm__DlVvX...s1600/9472.jpg
http://2.bp.blogspot.com/-jKRgPOIlCs...00/xt3083b.jpg

St?phane

[aditya]

A transformer is a transformer, and any of the types will do the job.

The basic difference between an autotransformer and a conventional one is that the autotransformer does not provide that important "isolation" thing between the primary and secondary, as both are part of the same common winding. But as a result of this they also gain in efficiency & cost as the iron-copper requrement & losses reduce by half. Capacitive losses and resonant points also diminish quite a lot.

The OP already has a conventional output trafo built-in to the amp and terminated at 200 ohms. So ideally speaking anymore isolation is unnecessary, and a suitable autotransformer should suffice the needs (if one finds one). But the UTC LS-33 that "AB" has sited is of very good quality also, and will do the job equally well if not more. May be it is a bit costlier compared to a similar but of the autotransformer variety.

[sanhanul]

Amplifier power was precious and expensive in the early days.

http://www.oswaldsmillaudio.com/imag...s/DSC_0691.jpg

That is a good point. And This RCA transformer looks sexy I believe UTC makes very good trans but the shape of UTC trans doesn't really fit to my tasts sometimes^^. And I feel the UTC looks kind of too big for my amplifier
hmm....

Thanks for the information...