Changing from a 16 ohm cab to an 8 ohm cab.
- Thread starter XPAULPITT
- Start date
Chris of Arabia
Desert RATT
Re: Changing from a 16 ohm cab to an 8 ohm cab.
So long as the amp has an 8 ohm output, you should have no issues at all. If it only has a 16 ohm output, DO NOT CONNECT AN 8 OHM CABINET TO IT. you run the risk of damaging your output stages that way.
So long as the amp has an 8 ohm output, you should have no issues at all. If it only has a 16 ohm output, DO NOT CONNECT AN 8 OHM CABINET TO IT. you run the risk of damaging your output stages that way.
Chris of Arabia
Desert RATT
Re: Changing from a 16 ohm cab to an 8 ohm cab.
Which cabinet is it?
Which cabinet is it?
Re: Changing from a 16 ohm cab to an 8 ohm cab.
Its a little Marshall MG 15W head. A few months back I got a 1960 cab for it. It is 16 so there was no problem. I got a new head for that cab so now I want to get the little Marshall MG 412 cabinet for the MG head. Its only 8 ohms.
Its a little Marshall MG 15W head. A few months back I got a 1960 cab for it. It is 16 so there was no problem. I got a new head for that cab so now I want to get the little Marshall MG 412 cabinet for the MG head. Its only 8 ohms.
Chris of Arabia
Desert RATT
Re: Changing from a 16 ohm cab to an 8 ohm cab.
I tried to find the manual over at Marshall, but they only seem to list for their current range, which includes the MG Carbon series; I don't know how close the one you have is to that in spec. My guess, and it is a guess, is that they are saying the head can take two 16 ohm cabs for a combined 8 ohm load, which would suggest that one 8 ohm cab would be OK. It would be useful if we could locate the correct user manual though, as that should be quite explicit on the matter. Until you've confirmed it with the manufacturers advice though, anything you connect would be at your own risk.
I tried to find the manual over at Marshall, but they only seem to list for their current range, which includes the MG Carbon series; I don't know how close the one you have is to that in spec. My guess, and it is a guess, is that they are saying the head can take two 16 ohm cabs for a combined 8 ohm load, which would suggest that one 8 ohm cab would be OK. It would be useful if we could locate the correct user manual though, as that should be quite explicit on the matter. Until you've confirmed it with the manufacturers advice though, anything you connect would be at your own risk.
IM4Tone
New member
Re: Changing from a 16 ohm cab to an 8 ohm cab.
For solid state amps, going less than the rated minimum can damage the amp; higher will not cause any problems except for the loss of volume.
For tube amps, USUALLY (if it is a reasonable quality OT), the single tap output transformer is safe to mismatch one step above and one below the rating (i.e. an 8 ohm OT running either 4,8, or 16 ohm load). Many tube amps have multiple tap transformers allowing perfect match for 4,8,and 16 ohms (and sometimes 2 ohms). It is a greater risk to run a tube amp with a higher load than specified as opposed to a lower one. For me, I won't run mismatches and have opted to use a Weber Z-matcher device that allows nearly every combination of amp and cabs to be correctly matched. If you tinker a lot it is a worthwhile $100 investment. About the same cost as one decent speaker.
Sounds to me as if a single 8 ohm load will be fine. Most all dual outputs are parallel connections, so 2 16 ohms in parallel yields an impedance of 8 ohms. I wouldn't hesitate to use a single 8 ohm cab.
For solid state amps, going less than the rated minimum can damage the amp; higher will not cause any problems except for the loss of volume.
For tube amps, USUALLY (if it is a reasonable quality OT), the single tap output transformer is safe to mismatch one step above and one below the rating (i.e. an 8 ohm OT running either 4,8, or 16 ohm load). Many tube amps have multiple tap transformers allowing perfect match for 4,8,and 16 ohms (and sometimes 2 ohms). It is a greater risk to run a tube amp with a higher load than specified as opposed to a lower one. For me, I won't run mismatches and have opted to use a Weber Z-matcher device that allows nearly every combination of amp and cabs to be correctly matched. If you tinker a lot it is a worthwhile $100 investment. About the same cost as one decent speaker.
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