Westrex purchased 100s of these PCBs from Crimson through he 80s and 90s. They should still be working. New electrolytics will help, plus a higher power Zobel load R29, 1W film should fit in OK.
The Farnell ones have a current gain bandwidth product of 200kHz. The Toshiba ones were 3 MHz. The slower ones would have significant cross conduction in class B at high frequencies due to hole storage. However they would likely be OK on music signals.
Genuine Toshiba
The Toshiba devices has clear red lettering on the can. On the underside the older Toshiba devices had an asymmetrical dumbbell/mushroom shape as part of the way the can was pressed. Two photo files of genuine devices are attached. The 2SD424 were even better and will do a good job of replacing the 2N3773s.
"Any advice on how to spot genuine Toshiba 2N3773 T03 transistors, I recently bought some on ebay and they didn’t have the lettering as in most pictures, the base seems thick enough though ?"
The Toshiba devices has clear red lettering on the can. On the underside the older Toshiba devices had an asymmetrical dumbbell/mushroom shape as part of the way the can was pressed. Two photo files of genuine devices are attached. The 2SD424 were even better and will do a good job of replacing the 2N3773s.
"Any advice on how to spot genuine Toshiba 2N3773 T03 transistors, I recently bought some on ebay and they didn’t have the lettering as in most pictures, the base seems thick enough though ?"
@ bepowell
I made a nice find in France not long ago, I send you one or two photos when I have a moment 😉
I made a nice find in France not long ago, I send you one or two photos when I have a moment 😉
Good for centre channel for cinema 🙂
I use a pair of 7 series modules which Brian had reworked, and they are superb, so an extra module would be good to have. Also the westrex box contains other goodies. My grandad worked for WE from before the war and continued working for the cinema's with westrex as his main supplier up until the 80's.
I use a pair of 7 series modules which Brian had reworked, and they are superb, so an extra module would be good to have. Also the westrex box contains other goodies. My grandad worked for WE from before the war and continued working for the cinema's with westrex as his main supplier up until the 80's.
it's good to know ! (for Westrex modules) 
I've been tracking a pair of 640s in original condition for years
I've been tracking a pair of 640s in original condition for years
I have created a website with most of the important Crimson Elektrik schematics and info. Let me know if anything is absent and I shall add it into the site.
See https://brianpowellaudio.co.uk/
See https://brianpowellaudio.co.uk/
I just bought another westrex cinema amplifier but this time with a issue 3 module. With all the other boards inside it's tempting to build a stereo preamplifier from them. They come with HY60 modules too, for the booth. All the power supply caps are suspect after all this time. The previous, issue 5 module works perfectly straight out the box so I'm hopeful for this one.
I am often surprised how many 80's amplifiers come back to me and the reservoir caps are still 100%. Generally they test good on correct capacitance, ESR and leakage. Most owners do want them renewed however, 40 years is pushing your luck with aluminium electrolytics. Reset the the bias and renew all the electrolytics on the PCB. Don't up the small rail decoupler values just replace with preferably 100V ones. I have issue 5 PCB in my spares. Issue 3 can be converted to issue 4. The XO distortion is better on issue 4.
As we are walking the path that`s called life, we inadvertedly pick up different pattern of behavoir from our fellow walkers. Such a fellow is Brian Powell. I was a young student in Kritiansand, Norway, in -78. I had just finished my military service and started engineer school. I bought two CE1704, that I installed in a power supply frame that I had gotten hold of. The transformer was a twin 44VAC, so I had to series connect my 50V caps. Long story short, I had an accident and destroyed one channel. Packed it up and sent it back to Crimson with an explanation about what had happened. A couple of weeks later it came back, fixed with a note saying: As the fault was possibly our we have repaired it at no cost.
I have been making amplifiers myself for the last thirty years, and have bestowed upon my customers the same curtesy Brian gave me. Free repair no matter the age, if neglect was the reason sometimes the customer have had to pay.
We both love music, and electronics aids us achieve that goal.
Roar Malmin
I have been making amplifiers myself for the last thirty years, and have bestowed upon my customers the same curtesy Brian gave me. Free repair no matter the age, if neglect was the reason sometimes the customer have had to pay.
We both love music, and electronics aids us achieve that goal.
Roar Malmin
The CE module data is on my website (search Brian Powell Audio). Please contact me if you have a specific query.
Brian
Brian