Bottlehead Forum

Bottlehead Kits => S.E.X. Kit => Topic started by: Ivan303 on January 22, 2021, 03:08:24 AM

Title: S.E.X. bridge to monoblocks
Post by: Ivan303 on January 22, 2021, 03:08:24 AM: Built two of the new model S.E.X. amps and currently have them bi-amping my horns.

Can I bridge the two amps to mono?

Parallel?

Series?

Safely without blowing things up?

TIA
Title: Re: S.E.X. bridge to monoblocks
Post by: Thermioniclife on January 22, 2021, 04:18:30 AM: Yes you can bridge them. Wire the transformers for 4 ohm operation then remove one of the 0 ohm jumpers on the speaker output terminals. now connect the left speaker positive to the right speaker neg terminal. wire your speaker to the remaining red and black speaker terminals. Use a y connector on the input jacks.
Title: Re: S.E.X. bridge to monoblocks
Post by: Paul Birkeland on January 22, 2021, 06:09:16 AM: While we do definitely like series bridging output transformers, the headphone jack on the SEX amp makes that a bit more difficult.

Which impedance do you have the SEX amps wired for right now?
Title: Re: S.E.X. bridge to monoblocks
Post by: Thermioniclife on January 22, 2021, 06:29:51 AM: Hey PB, In what way is the headphone jack problematic?
Title: Re: S.E.X. bridge to monoblocks
Post by: Paul Birkeland on January 22, 2021, 06:37:04 AM: Each output of each output transformer goes to the headphone jack, and the signal - connections from each OT are both connected to the sleeve terminal on the HP jack. If you wire left speaker positive to right speaker negative, you'll short the output of the left channel even if the jumper isn't there.
Title: Re: S.E.X. bridge to monoblocks
Post by: Thermioniclife on January 22, 2021, 06:44:40 AM: I guess I'm lucky because I use the left pos. and right neg.
Title: Re: S.E.X. bridge to monoblocks
Post by: Paul Birkeland on January 22, 2021, 07:54:14 AM: It's no luck vs. no luck. you can wire all the binding posts together on a SEX amp and not damage anything. What you have in that photo is not a pair of bridged SEX amps if the HP jacks are still wired in.
Title: Re: S.E.X. bridge to monoblocks
Post by: Thermioniclife on January 22, 2021, 12:12:16 PM: PB, That explains why I was not impressed. I just disconnected the sleeve wiring and connected them separately and gained the few Db I was expecting. Should have thought this through at the time, Thanks
Title: Re: S.E.X. bridge to monoblocks
Post by: Paul Birkeland on January 22, 2021, 01:17:26 PM: Always glad to help.

-PB
Title: Re: S.E.X. bridge to monoblocks
Post by: Ivan303 on January 24, 2021, 03:28:26 AM: Quote from: Paul Birkeland on January 22, 2021, 06:09:16 AM
While we do definitely like series bridging output transformers, the headphone jack on the SEX amp makes that a bit more difficult.

Which impedance do you have the SEX amps wired for right now?

8 Ohms but can easily change to 4 if that's a requirement for bridging.
Title: Re: S.E.X. bridge to monoblocks
Post by: Ivan303 on January 24, 2021, 03:36:42 AM: Quote from: Ivan303 on January 24, 2021, 03:28:26 AM

8 Ohms but can easily change to 4 if that's a requirement for bridging.

And I have no intention of using the headphone jack on either of the two S.E.X amps as I have a headphone amp I am happy with.
Title: Re: S.E.X. bridge to monoblocks
Post by: Paul Joppa on January 24, 2021, 05:04:30 AM: Quote from: Ivan303 on January 24, 2021, 03:36:42 AM
And I have no intention of using the headphone jack on either of the two S.E.X amps as I have a headphone amp I am happy with.
Not much point in a headphone jack on a monobloc!
Title: Re: S.E.X. bridge to monoblocks
Post by: Deke609 on January 24, 2021, 05:42:50 AM: Quote from: Paul Joppa on January 24, 2021, 05:04:30 AM
Not much point in a headphone jack on a monobloc!

I have tentative plans to convert my Kaiju headphone amp to monoblocks with one Neutrik 3 pin output on each monoblock. :)
Title: Re: S.E.X. bridge to monoblocks
Post by: Ivan303 on January 30, 2021, 03:11:52 AM: Quote from: Paul Joppa on January 24, 2021, 05:04:30 AM
Not much point in a headphone jack on a monobloc!

Heard that!

So I'm guessing I should strap the outputs to 4 Ohms and then somehow disconnect the outputs from the headphone jack and wire the two output transformers' outputs in parallel while disconnecting one of the '0' ohm resistors?

Seems possible.