Greater Toronto Area DIY meetup

Hi ticknpop
An old stock DH200 (and possibly assembled as a kit) could not be in the proper original state.... Even then the DH200 sound seems to has been somewhat a bit controversial at the time based on some reviews....maybe caused by the higher resolution with bad sources or material at the time (speculation...).
Of course the new pcb based on Bob Cordell new redesign seems an attractive solution... however not for me since I have sold all my DH200 amps...

Fab
 
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I'm interested! :)

Just think guys ... no snow possible. What a wonderful concept!

As always, I'm in Georgetown and would be more than happy to give someone a lift. So rather than burning gas in two cars or more, let's carpool. It can give people a chance to really talk between each other.

-Chris
 
17-foot labyrinth sub? oops, big time
there is an art in identifying these smells, comes with practice. Sorry to hear of the non-kitchen smells. we have steak in the house tonight.
I burnt out my new amp design the other day, learnt the thermal compensation can only compensate soo much, thermal loop gain, that stuff. No big deal, learn by blowing crap up. There was a LM35 & ckt/relay to disconnect the speakers, light the led but that won't save the amp from a thermal run away event. Mains fuse blew eventually, all 4 shorted, shows a well matched amp :) Easy to repair, MJE1503x drivers are still fine. Smoked emitter resistors. Could advance the design, to include a opto to cut the bias. next rev. Couple of more parts and signals.
I was using the cheaper FJL 150W devices :) The amp was sounding really nice. A solid 150W amp. I did measure the thd, it was in the weeds of the Amber analyzer. I will be able to show it next time we meet up.

Happy easter guys
Rick
 
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There seems to be enough interest between here and the Canuck Audio Mart website for the BBQ to happen.

I will have a Toshiba 170/74 jfet cascode preamp feed from Dexa regulators.
And i should be finished ( hopefully) the Perreaux 3150 rebuild, looks to do about 450 w/ch into 8 ohms. cascoded front end, dc servo added, beefed up PI filtered power supply with Quasimodo snubbed soft recovery hexfet bridge , passive component update, blah, blah, blah....

Rick, do you need a Hafler DH 200 for the Cordell boards ?

If only we could convince Ben to bring the bass labyrinth. Did anyone say Tequila?
 
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Hi Rick,
Sorry to hear about your education, but you did learn a lot about what happens when everything goes pear-shaped. Fuses are a time delay device. It has to build up enough heat to melt the element. I would change the drivers as well, and they are cheap.

Looking forward to hearing your amp next time!

Hey Dave,
Your events are must-see deals. You know that ... right?

I'd like to throw out a suggestion. How about name tags so we know who we are talking to as far as screen name is concerned. Real name could be optional.

-Chris
 
Rick, do you need a Hafler DH 200 for the Cordell boards ?
Yes, eventually the boards will need a home, assuming all goes well. I can test stand alone, for now, I sent a set to Bob to test them out in his setup. He still has to review the design layout, I jumped the review to get it done, so who knows.
Chris, tag you're it, dollar store name tags :) Change the drivers, okay, need some spare MJE1503x? happy Easter folks
 
Did not even know of GTA Audiophile group. Not DIY from what I can determine

Chris,

FYI, the MJE15032,33 drivers survived my torcher test. Damn hard to fry them. Even the 220mohm emitter R's survived.

Here is a pic of the DH220C getting ready for the OPS test and the new Bob Cordell amp that is a whole chapter in the new book.
 

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