new orange user. need some advice

[20Alextheman]

Hy all

yesterday went to the rehearsal to try my dual terror.
The amp works like a charm and I already plan to sell my big muff pi cause I don t seem to need it anymore and also doesn t seem to work very well with the DT.
The other problem I have is that the damn cabinet that I used( is not mine) is only 4 Ohm.. so I didn t wanted to risk playing through. I got the cabinet from the other guitarist( which seems to be self made.. ) cause he said it s 8 Ohm but he wasn t so sure. I plugged in and it worked. no explosions no fireworks. However i don t trust his cab that much since i m not sure it s 8 ohm.
Question: do actually DT work with a 4ohm cab or I ll have to buy a 8 Ohm cab ? I m asking cause I found a german site that tells that actually there is no problem cause most of the cabs are anyways 4 ohm even if on the cab is wrote 8 ohm and bla bla. shall i trust it?
http://www.nubert.de/downloads/ts_impedanz.pdf" onclick="window.open(this.href);return false; here is the link.. is in german and to long to translate so pls use google translate if interested in reading it.

Ty for your help.

[a.hun]

Well the amp is designed to work with either an 8 or 16 ohm load. You could run a 4 ohm cab from the 8 ohms output but that is a low direction mismatch pretty much on the limits of what is (reasonably) safe.

Most (VALVE!) amps with a good output transformer and healthy power valves will survive a mismatch from half to double the correct matching impedance. The power output (either direction) will be a bit lower and the tone will also change some, but they'll usually survive. Going low (as you'd be) is harder on the power valves so they'll wear faster. But unless one fails there is no major risk to the amp, and probably not even then unless you are unlucky. Running into a too high impedance is riskier to the amp itself. Beyond a certain point you can burn the OT out - can happen fast - no warning!

The risks of a mismatch are increased by the severity of the mismatch and by how hard you run the amp. Just to test an amp temporarily running at moderate volumes from the 8 ohm output to a 4 ohm speaker load shouldn't normally be a problem. never any guarantees though so always best to match impedances correctly.


Andy.

[20Alextheman]

oh ok ..so the only non risky chance for me would be to buy a new cab with 8 or 16 ohm ?
found this http://www.sengpielaudio.com/calculator ... AndOhm.htm" onclick="window.open(this.href);return false;
tha guy has a point... idk if i should listen to him and connect the DT with the 4 ohm cab or buy a cab that matches the amp

[a.hun]

Franky I'd ignore those articles you found and listen to this advice:
http://www.thegearpage.net/board/showpo ... ostcount=6" onclick="window.open(this.href);return false;

Yes you van get away with a degree of impedantie mismatching with valve amps, but the outputs are marked with specific impedances for a very good reason - valve amplifiers have output transformers and ARE designed as impedance matching devices. The potential dangers of mismatching - especially running into a too high impedance - are very real. Many many blown output transformers (the most expensive bit in your amp!) can testify to that...

Note that this advice doesn't apply to solid state amps which are very different beasts!


Andy.