Einstein Combo hooked up to external cabinets

[adyb]

Hi guys,

I have three questions regarding my Einstein 50W combo and connections to external peripherals.

1. The combo is connected to the internal speaker via the 16Ohm speaker output, as set up from the factory. I addition, I have a speaker cable from one of the 8Ohm outputs running into a Palmer Speaker simulator which turns the loudspeaker output into a line signal, which in turn is fed to a TC Electronic G-Force, and from the G-Force into a Marshall Valvestate 8008 power amp and into two 1X12 Bogner speaker cabinets. All this gives me a very pleasing wet-dry-wet setup. However, the output tubes have been ruined two times already in less than three years, and I have hardly gigged with this amp. Can the reason for this be that the output stage is "seeing" another load impedance that it should?

2. I'm going on tour this spring and I'm looking for an extra cabinet to hook up with my Einstein, in conjunction with the internal cabinet. What kind of cabinet can I hook up to the Einstein in matter of impedance? The manual says, I quote:

"Einstein has 5 speaker jacks. 1 for a 16Ohm load, 2 for 2 16Ohm loads or 1 8Ohm load, and 2 for 2 8 Ohm loads or 1 4 Ohm load. Confusing? Oh yes! Just do what it says on the jacks, and you’ll be fine"

Does this means that I can hook up everything to the Einstein as long as the cabinet impedance matches the output impedance of the Einstein? For example: The internal speaker connected to the 16Ohm output and a 2x12 cabinet to a 8Ohm output if the 2x12 cabinet's impedance is 8Ohm?

I have asked my dealer about this, but they're kind of stuck here.. I have also looked around in this forum but haven't found anything... I would appreciate an answer !

Best regards,
Atle Dybå
Norway

 

[duesentrieb]

H Atle, the way you are running it the output transformer wants to see 1/16 + 1/8 = 1/R. Thats 5,333 Ohm.
So please hook speaker and the Palmer to the "2x8" Ohm (=4 Ohm). Thats the closest mismatch. So use the two speaker jack which are closest to the center of the amp.

I'll post a pic . . .

 

[duesentrieb]

.

 

[adyb]

Hi,

thanks for your answer! I think I understand now. Let's say I want to hook up another cabinet to the Einstein in conjunction with the internal speaker; Should this cabinet be 16Ohm so that I should connect both the internal speaker and the external speaker to the 8Ohm output jacks because the total impedance wil then be 8Ohms? (I will then run the signal through the Palmer and not use the internal load in the Palmer). Or can I hook up other types of cabinets with different impedance? Will the output stage see all the cabinets in parallel?

Atle

 

[duesentrieb]

If you have another 16 Ohm cab, both should be connected to the 8 Ohm out (or 2x16) - those jacks (counting from the left) # 2 and #3.

An output transfomer has "just" three outs: 16, 8 and 4. Normally one would expect three jacks only, but since some people want to run 2 cabs (or a Palmer) the outputs for 8 and 4 Ohm are "doubled" (wired in parallel), so that you can hook 2 cabs a 16 Ohm (=8) or 2 cabs a 8 Ohm (=4) to your amp.