Cool. That's a horse of a different flavor. Direct radiators have fewer quirks than the A5/A7 style of too-small front horn and backloading.
All good fortune,
Chris
All good fortune,
Chris
The Brook has the Lundahl 1623 AM core but I don't like the highs as much as the 300b (Edcor CXSE25). The 1623AM have ~ 500hrs and I've lost hope with the 'break in' to happen, whatever that means 🙁
The negative bias with the 700R resistor in the PS was quite a challenge as it gets really hot. After the initial try of a simple resistor across the supply it was changed to a Vishay 25w attached to a home-made heatsink. This seems to work well.
The negative bias with the 700R resistor in the PS was quite a challenge as it gets really hot. After the initial try of a simple resistor across the supply it was changed to a Vishay 25w attached to a home-made heatsink. This seems to work well.
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Chris, is there any designs you can recommend looking at - with EQ built in.
I'm in the process of building the TSE-II_2A3 to biamp the HFs on the 604e. I don't mind the 3-4W I'm expecting to get with a supply of "HT@350v | Edcor GXSE15-5K | RCA-2A3s (1947)". These tubes can take the extra V's and the HFs should love it.
I'm switching the build of the 2A3 to the Tubelab board, don't want to derail this chat about the Brook 12A's. Cheers.
After a 14 year run, the TSE must DIE!
After a 14 year run, the TSE must DIE!
Seeing the picture of your beautiful system, it's apparent that a lot of thought and planning has already gone into it. Suggesting any specific changes would be foolish, but a stranger might suggest somethings generally, and only as possibilities to consider.
If building amplifiers dedicated to a specific speaker, the DIYer has the opportunity to include "crossover" functions, high and/or low pass filters, specific EQ (if not too complicated - but even a Linkwitz transform is possible if desired) and level adjustment in that speaker's dedicated amplifier.
In a system like this, a line level (of your choice) flat signal would drive whatever number of paralleled amplifiers, each with the proper filtering and EQ dedicated for its personal speaker.
To do things this way, you would need to know (!) enough about your speakers to specify the filtering and EQing required of the various amplifiers. In return, you would have the cleanest possible signal path, but would be forced to forego any advantages available from time shifting - an issue with non-coincident speaker drivers. Sorta-kinda possible analog, but usually really only practical with DSP.
Sorry, more than you wanted to read, but just throwing some things out there. Maybe interesting some day.
YOS,
Chris
Thanks Chris. The idea is a all tube system. After the 2A3s, I'll build the SSE with EL34s.
I have some NOS tubes of various sort - Mullard, Philips, RTF, Tesla. I'm hoping they won't sweat the 430v I want to give a try.
I have some NOS tubes of various sort - Mullard, Philips, RTF, Tesla. I'm hoping they won't sweat the 430v I want to give a try.