Guitar Related Ramblings - Vero, P2P, Vintage Effects and Amps
Vintage fuzz, guitars, amps, guitar effects and other things that make noise.
Friday, March 7, 2025
TRANSFORMER: A&R 2504 output transformer
Saturday, March 1, 2025
ETONE: Gold 12" Guitar Speaker
Etone speakers are a bit of a hidden gem in the guitar world, with their roots firmly planted in Australia. Manufactured in Sydney, these speakers were often considered the local (and cheaper) alternative to Celestion.
Unfortunately there isn’t much detailed information available on the specs, but it's widely believed that they have a ceramic magnet and handle around 40 watts of power.
This particular speaker dates from 1975, as suggested by its code (thanks to the comment from Peter F). While the previous owner mistakenly marked the model with "975," that’s actually the date code, not the model number.
One of the most interesting things about the Etone gold speakers is their unique construction. Unlike most speakers, the frame and basket are one solid piece, which means the magnet is mounted from the front directly into the bell.
I have two Vox AC15 amps, the newer AC15C1X with a celestion blue and an older AC15CC1 with a wharfdale GSH12-30 speaker. Naturally the wharfdale was the one that I swapped out - I prefer the etone over the wharfdale. The wharfdale wasn't terrible, it just wasn't a lively sounding speaker by comparison (if that makes any sense to you).
Thursday, February 20, 2025
AWA: Fox Sound Systems, 25w PA Valve Amplifier
Branded as Fox Sound Systems, this is really an AWA PA1003. I couldn't find any information on Fox Sound Systems, Sydney. My guess is that they were an installer who ordered unbranded amps directly from AWA for their installation work—possibly for schools or government buildings. But who knows?
I already own one of these, so when I saw this and the seller dropped the price to a reasonable amount, I snapped it up. I suppose I'll have to sell one later.
The differences between this one and my other unit are minimal. The main ones are that this amp has the optional low-impedance mic transformer on the input, and the phase inverter uses a 12AU7 instead of a 12AX7.
I recently started work on this by pulling out the microphone transformer and giving it a run with a guitar - it ripped. I'm now wondering how much I want to mod it for guitar... I might try and keep change as minimal as possible.
Sunday, February 2, 2025
UTILITY: Speaker Cab Impedance / Speaker Switch
When I set out to build a proper test cabinet for amp building, I came across a great switch wiring setup that perfectly suited my needs. With the parts I had on hand, I was able to put together a versatile cab without risking damage to my favourite speaker cabs. There are of course commercial products that achieve the same thing, and sometimes more. But this is a DIY blog right.
Why a test cab? I already own several cabinets that I really like, however, I was a bit concerned about accidentally destroying a vintage speaker. A dedicated test cab allows me to safely experiment with different speaker loads without worrying.
What You’ll Need
- A twin-speaker cabinet with 8-ohm speakers
- A 3-pole, 4-position rotary switch (Make sure it's a sturdy one, ideally rated at a couple of amps)
There are four switch positions, covering the most common loads:
- The first two switch positions isolate the individual speakers, providing an 8 ohm load. Handy if you have two different speakers in a cab that you want to isolate.
- Position three is both speakers in series, providing a 4 ohm load
- Position four is both speakers in parallel, proving a 16 ohm load
4-WAY SPEAKER / IMPEDANCE SELECTOR
TEST CAB
Saturday, February 1, 2025
VOX: Tone Bender
Vox tone bender - two knobs and three silicon transistors. It's kind of a silicon MKII with clipping diodes on the output. It’s loaded with a Jen FZ III circuit, which I wasn’t aware that it was ever used in a Vox.
Photos from someone that grabbed a fuzz from me recently - Initially I had no idea what the circuit was, so I thought I'd post it here.