Hudson Electronics Broadcast - AP

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Tomrcarre
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Post by Tomrcarre »

Hudson Electronics has recently come out with a new version of the broadcast with two silicon transistors and a more striped down control set, in partnership with Ariel Posen exclusively for Andertons Music in the UK.

To quote Hudson Electronics website
At the heart of the Broadcast-AP – as the name may suggest – is the same circuitry as the Broadcast. A class-A discrete, transformer-coupled circuit, designed to saturate in a unique way reminiscent of certain recording and broadcast consoles.

We took the low-gain side of the standard Broadcast as the starting point. Together, Ariel and I exchanged the Germanium transistor for a Silicon and used an OEP transformer – the OEP transformer saturates and distorts less below 100Hz compared to the Triad transformer used in the standard Broadcast. These two changes together give the Broadcast-AP a darker, smoother, more powerful tone compared to the standard version. Greater weight in the lows, whilst retaining the open highs and upper-mids, giving the Broadcast a ‘3D’ effect.

The control layout features both LEVEL and GAIN TRIM potentiometers and a switchable high-pass / low-cut filter – 100Hz @ 6dB/oct. The GAIN TRIM control has 12dB more gain than the low-gain side of standard Broadcast, allowing the Broadcast-AP to cover ground from clean boost through to medium gain overdrive tones. In addition, the gain of the pedal can be increased via an internal trimmer and – when pushed to the max – the sound becomes overloaded, broken and fuzzy. The high-pass / low-cut filter can help keep the low end together, especially when driving amps at higher gain and volume levels.
I've managed to pull a gut shot from an andertons video, i had to cut the volume pot off the screen cap to fit it in the shot but there's nothing else there anyway.

Image

okgb
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Post by okgb »

Bogner used some but I was wondering what took so long for builders to start using signal transformers , if only for a gimmick
In this case emulating a recording console [ and it's overload ] , you'd think an amp transformer would be an obvious try ?

Anyone know which model OEP transformer is used here ?

Tomrcarre
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Post by Tomrcarre »

From what I can gather from the original broadcast it is being used as an inductor within an RLC filter to change the resonant peak but I may be wrong.

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turbofeedus
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Post by turbofeedus »

But but but... without the stripboard, from where will all the toan come?

Was the source of this circuit ever discovered? It was supposedly some old radio preamp right?

Tomrcarre
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Post by Tomrcarre »

More than likely it came from an old transistor manual with a list of simple radio and broadcast circuits! I’ve seen some people suggest it came from a neve preamp but I highly doubt that being it’s origins, either way it’s a cool circuit that sounds fat so it’s all good in my book. :thumbsup

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plush
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Post by plush »

okgb wrote: Anyone know which model OEP transformer is used here ?
I bet it's Bourns LM-NP series

OEPs are much bigger.

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Post by okgb »

The knobs suggest a Neve console module , whether that is designed to make you think that, I don't know
[ class A circuit running on single end 30 v like the 1073 pre/ eq module ]
also I thought I heard /read this and it being an OEP transformer, input or output or as an inductor ?

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plush
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Post by plush »

okgb wrote:The knobs suggest a Neve console module , whether that is designed to make you think that, I don't know
[ class A circuit running on single end 30 v like the 1073 pre/ eq module ]
also I thought I heard /read this and it being an OEP transformer, input or output or as an inductor ?
Transformer.

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turbofeedus
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Post by turbofeedus »

Tomrcarre wrote: either way it’s a cool circuit that sounds fat so it’s all good in my book. :thumbsup
I stuffed my clone with lard, but I didn't really hear a difference. Any tips?

teddeeh
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Post by teddeeh »

Its definatly an OEP transformer.
Ive experimented with different ones

I

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modman
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Post by modman »

Why are we fantasizing about old mojo recording consoles when there is a gutshot to study? Clearly there are similarities with the original unit: the 330pF, 330nF and the 6-7 elcos. But the marketing copy says: we replaced the Ge with a silicon.... but not a run off the mill plastic case thing.
Broadcast AP.png
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