Hi, just an update how things are going, Had to change a BASS driver in my main system due to distortion caused by a badly re-foam attempt by somebody else. Got to listen to music (Loudly ) in the work shop as I potter about.
I have two pair's of these HB1's, both were fairly cheap , 1 pair with a rubbing cone and a bad re-foaming job for the other. The bad re-foaming pair sounded the best !!!! . Deeper richer sounding. Changed the driver with the rubbing voice coil. Had to change the other driver in that pair to balance out the sound. Lucky I had a driver left over that I could use. Both pairs do not sound as good even when replaced with the correct driver's from manufacturer.
Tim Mellow 25W
Slow progress so far on the Tim Mellow 25W amp so far, still having issues with getting all the components.
D1-D4 FR605G main rectifier's no stock available from all the major supplier's , looks like long delivery times they or have gone obsolete. Managed to get hold of some FR607G's same spec with higher PIV (1000V) so they will have to do. No luck sourcing 1k/10k 20 turn preset pot's can only find 10 turn pot's so far.
Thought I would start building the power supply as I am eager to get this Amp up and running.
Possible Capacitor layout to start with. Added Aluminum U channel bar for support for the chassis as 8-10kg
of weight from the transformers was slightly bowing chassis.Used the U bar to fit the Tag board to so I will be
able to build the power supply out of the chassis and test before other components are fitted.
Using Tag Board to fit the capacitors
Cap's soldered to Tag Board
Did not like the color of the face plate for the A09 , light orange/yellow ??? so I decided to polish off the anodized color. Just a rough polish so far it looks great . Hope to get a mirror finish when finished.
Finding a place for the VU PCB and transformer, PCB 9V AC supply needed, should of checked before purchasing , only 5v, 6.3v and 315v supplies available with the A09 so had to get extra transformer .
Only place available that could accommodate Transformer and PCB , tried a better capacitor (replaced with a 270uf 500v) for the B+ instead of the Chinese cheapo. Must check dimensions next time just slightly too big to fit in available space.
Replaced Main's On/Off switch with a better one. Shaft spline broke after fitting knob.
Thought I would check resistance of the Pot I got for the Skunkie Tube Headphone project and 25w Amp Pot.
If you don't check the components before you install them I would from now on. It seems the quality is not what it used to be back in the old days.