I purchased three Innova 3320's from Amazon and a bunch of different clips (see previous photos). All 3 cost less than a fluke and it made the biasing procedure super easy. Takes 5 minutes with 3 meters. With one I wouldn't have realized how interactive both pots are and it may have taken me over an hour to adjust for DC offset.
Since most source components have an output coupling capacitor, the DAC's smoke/smell
from the DC at the amp inputs may just have been a small resistor to ground, which you
can do without, or easily replace.
Because I had a work-related, frustrating mishap this morning, I decided to switch up the Chi in my home office (which is really my living room with my main listening gear, plus my work stuff).
I swapped out my VFET SE with my F5 and was really struck with how great the F5 is. I think it matches my Manzanita-ish speakers better. I heard some new things in familiar songs that I haven’t before.
Case in point: The Shins ‘New Slang’ has a bit of wooden-fish-like percussion in it that I never noticed before. But today, it was clear as day. And I know I heard that same recording recently.
The F5 is a fantastic amplifier. Happy listening, everyone.
I swapped out my VFET SE with my F5 and was really struck with how great the F5 is. I think it matches my Manzanita-ish speakers better. I heard some new things in familiar songs that I haven’t before.
Case in point: The Shins ‘New Slang’ has a bit of wooden-fish-like percussion in it that I never noticed before. But today, it was clear as day. And I know I heard that same recording recently.
The F5 is a fantastic amplifier. Happy listening, everyone.
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With my LX Mini system I'm using an F5 for the full range transducers and an F5 Turbo for the low end transducers. The combination of creations of two of my favorite folks in the Audiophile kingdom is a wonderful thing. Also using the Pass active crossover to feed them. Lots of karma right there!
Thanks Dennis. I didn't discover Linkwitz's endeavors until after his passing. But I was surprised with his and Nelson's friendship Linkwitz didn't put more emphasis on the amplifier quality than he did. Maybe it was that he was trying to make his creations more of an every-mans system and the number of amp channels required with the active crossover configuration would be very expensive if higher quality amps were utilized. Especially with the earlier Orion and 521 designs. I think Nelson should do a "Burning Amp Tribute" with a pair of 521 using his amplification and crossovers to drive everything.
My F5 has gotten run in properly in the last month or so, I'm going back today to check the bias once more to set against drift.
I remember reading somewhere that some folks make RCA plugs which ground the inputs in order to make sure the bias readings are stable -- can anyone confirm this practice?
I remember reading somewhere that some folks make RCA plugs which ground the inputs in order to make sure the bias readings are stable -- can anyone confirm this practice?
That's highly advisable during the biasing of any amplifier to keep noise out. Just solder a short wire
between the RCA plug's ground lug and center pin. You can buy them already made up also.
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Hey guess what everybody I have more questions. Thanks for talking to me so much, I am loving this process.
As mentioned above, my amp is finished, stable, run in, and biased. Life is good.
Now I'm turning my attention to a new DAC stage. I only run 1 input, so I don't need any switching - I only need some form of attenuation. I'd like to develop a system that's in 2 boxes: source + power stage. Ideally I would avoid any redundant gain stages if I don't need them. However, the F5 has relatively low gain.
I'm aware of 2 options:
- Build my DAC with higher Vrms by adjusting resistor values in the I/V stage
- Adjust resistors in the F5 to make it more sensitive as per 6L6's post ages ago.
Does it make more sense for me to squeeze more voltage from my source or increase the gain of the F5? Or maybe I'm missing something else entirely
As mentioned above, my amp is finished, stable, run in, and biased. Life is good.
Now I'm turning my attention to a new DAC stage. I only run 1 input, so I don't need any switching - I only need some form of attenuation. I'd like to develop a system that's in 2 boxes: source + power stage. Ideally I would avoid any redundant gain stages if I don't need them. However, the F5 has relatively low gain.
I'm aware of 2 options:
- Build my DAC with higher Vrms by adjusting resistor values in the I/V stage
- Adjust resistors in the F5 to make it more sensitive as per 6L6's post ages ago.
Does it make more sense for me to squeeze more voltage from my source or increase the gain of the F5? Or maybe I'm missing something else entirely
I think you need a preamp and the BA-3 front end is a nice choice, as it will really drive the F5 to it's potential.
I don't know that I do -- go with me here for a second as I use algebra for the first time since I was 18:
If P=V(sq)/R, --> 25w = V(sq)/8ohms --> V= 14.14v to drive the F5 fully to 25wpc at 8 ohms
If Av=20Log(Vout/Vin) --> 15.3db = 20Log(14.14v/ Vin) -->Vin = 2.43v to drive the amp to a full 25wpc at 8 ohms
So if I only need ~ 2.5 Vrms to drive my stock F5 to full rated wattage, then I could adjust one resistor value in the I/V stage of a DAC and cut out a whole preamp stage. Less boxes, less cost, more elegant.
Am I off here?