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April 14, 2026, 09:48:01 pm
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Hoffman Amps Forum image Author Topic: Amp getting a new OT- 4 & 8 ohm-what happens with the Negative Feedback wire?  (Read 297 times)

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Offline pbman1953

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I'm taking out the old 4 Ohm OT and installing a new OT with 4 & 8 ohm. What happens with the negative feed back wire?


Thanks

Offline sluckey

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Connect it to the 4Ω tap

Offline pbman1953

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Thank you!


 

Offline pbman1953

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I did a soft connect . Only ran wires to the same spots. After turning it on there's wasn't a howl so I suppose the wire were in their proper places but the sound is un-clear/ fuzzy.

Offline Esquirefreak

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What's a soft connect?

Offline pbman1953

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. Leaving the wires long before the permanent connection

Offline sluckey

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Why did you replace the OT? Did the amp sound un-clear/ fuzzy before you replaced the OT? Does this amp have a name? Schematic? Have you done any troubleshooting? Measured any voltages? Give us some background. So far you have offered zero clues for us to guess on.

Offline pbman1953

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ok, sorry for lack of detail , I thought this was a simple one because its been done before.

Reason for replacement - I have both 4 & 8 ohm cabs- versitility

Sound before - was fine , no issues

Amp Fender Super Twin

Voltages taken - not yet- what is first to test?

In the meantime , until I hear back, I'll look over anything to be sure there are not any bad connections














Offline sluckey

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Put the original OT back in the amp. If sound is fine, then the replacement OT was either incompatible or faulty or connected wrong. Give us the details on the replacement OT.

Offline pbman1953

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ok, I'll do that


The new one is a Heyboer Fender 012413
-HTS 5251

Offline pbman1953

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I found it. When I removed the main speaker jack and the extension jack I didn't reground it back to the 33k is was connected to
« Last Edit: April 12, 2026, 12:37:13 pm by pbman1953 »

Offline pbman1953

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The amp is all set and thanks for the help!







 


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