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The lounge Relax, take a break from photo and camera talk - have a chat about something else for a change. Just keep it clean and polite!

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Old 13th September 2018
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Bent Fenders (may contain valves)

So this is what I have been busy with this summer:



That's a hand built Strat that I customised with a pickup swap and clever wiring.

Then there is a little 2 valve Fender Champ 600 that I rehoused in a larger Fender box with a radical pre-amp redesign. So its the Fender amp that Fender never made.

Finally in front is my delinquent 4 valve Fender Pro Junior that I have spoken to harshly. I think it is starting to behave properly now.

In each case I have been chasing that perfect tone rather than "how loud can I make it". I actually reduced the output power on the large amp to stop if burning up valves. Obviously they got re-covered in tweed, which makes them sound better immediately.

These are return to basics amps. They came with just one or two knobs. No fancy tricks. Maybe after years of designing microelectronics I am reverting to childhood?

Pete
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Old 13th September 2018
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Re: Bent Fenders (may contain valves)

I know it's only rock n' roll but I like it.
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Old 13th September 2018
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Re: Bent Fenders (may contain valves)

A labour of love.
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Re: Bent Fenders (may contain valves)

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Originally Posted by Zuiko View Post
I know it's only rock n' roll but I like it.
Yes I do...
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Old 13th September 2018
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Re: Bent Fenders (may contain valves)

Valves, eh. That takes me back. What has it got for the output - a pair of 6L6's in push-pull ?


David
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Old 14th September 2018
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Re: Bent Fenders (may contain valves)

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Valves, eh. That takes me back. What has it got for the output - a pair of 6L6's in push-pull ?


David
Ah a fellow valve fettler... Well the little one is class A single ended with a 6V6 - that amp his just two valves. Lovely...

The big one is push pull EL84 which I re-biassed to class A. That amp has four valves and therefore counts as complicated

My next project with three valves will be single ended with a pair of 6V6s in parallel. No-one seems to do that so I thought I would design one..
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Old 16th September 2018
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Re: Bent Fenders (may contain valves)

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That's a hand built Strat that I customised with a pickup swap and clever wiring.
It seems to have had an organ transplant from a telecaster.

Harold
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Re: Bent Fenders (may contain valves)

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It seems to have had an organ transplant from a telecaster.

Harold
Absolutely. It has Tele metalwork but Strat like pickup arrangement
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Old 16th September 2018
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Re: Bent Fenders (may contain valves)

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Ah a fellow valve fettler...
Another one here.




They look wonderful Pete. You cannot beat valves, just as you cannot beat a good film camera! I love tinkering with analogue circuits whether thermionic valve or solid state, but digital just leaves me cold.

I am interested in you comments about redesigning the circuits of your various amplifiers. Few people realise that it is comparatively simple to modify valve circuits from one purpose to another. The only real obstacle is the amount of heat produced.
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Old 16th September 2018
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Re: Bent Fenders (may contain valves)

I thought the 'received wisdom' was that as loudspeakers are low impedance current driven, then their best driven from a low impedance current source - transistors. Any introduction of a matching transformer can only introduce distortion. Still, whose going to notice distortion with popular music!

Is everyone going back to the 1947 Williamson amp, then?

Jim
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Old 16th September 2018
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Re: Bent Fenders (may contain valves)

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Originally Posted by Naughty Nigel View Post
They look wonderful Pete. You cannot beat valves, just as you cannot beat a good film camera!
Yeah - and 'San Izal' toilet paper, Morris 10s, Brylcreem, use once carbon steel razor blades and Styptic alum sticks!

I expect you wear a wing collar, Nigel!

Jim
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Re: Bent Fenders (may contain valves)

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I thought the 'received wisdom' was that as loudspeakers are low impedance current driven, then their best driven from a low impedance current source - transistors.
You might think so Jim, but a good output transformer introduces little or no distortion, and seems to remove 'digital artefacts' from digital sound sources such as CD's.

The majority of the (very little) distortion produced by valve circuits is third order harmonic distortion, which actually enhances many genres of music.

Valve amplifiers also have comparatively few stages compared with solid state designs, (usually no more than three or four from pickup to output) which also helps to reduce distortion. Some solid state designs using IC's seem to have dozens of stages!
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Old 16th September 2018
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Re: Bent Fenders (may contain valves)

I wish someone would say something positive about digital - it would give me the excuse to say "I 1100100% agree!"



Jim
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Old 16th September 2018
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Re: Bent Fenders (may contain valves)

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Yeah - and 'San Izal' toilet paper...

Jim
Oh yes, we had that at school until it was replaced after pupil protests!

I think it was called Izal Medicated. There was another called Bronco which was just as uncomfortable to use.
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Old 16th September 2018
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Re: Bent Fenders (may contain valves)

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Originally Posted by Naughty Nigel View Post
Oh yes, we had that at school until it was replaced after pupil protests!

I think it was called Izal Medicated. There was another called Bronco which was just as uncomfortable to use.
We had to use both sides at the school I went to! When the supply had run out we used old cement bags.



Jim
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