Though a pot would function, you may want to consider that with a 10k pot turned all the way up the source would see a 5K input impedance (The 10K and the amp camp in parallel).
You may also want to consider that the feedback loop is dependent on the source impedance. In the case of a 10k pot set to the middle (resistive not rotational) this would add another 2.5K to R11. This would affect the feedback ratio. My guess is the effects on, gain, distortion (would go down, as feedback goes up), output resistance (and its neighbor damping factor) would only be negligible at 10K, not going to calculate, the funs gone out of it a bit for me. Just things to keep in mind, if adding a pot. This illustration might help visualize (hope no one minds I used the digital NOT to represent the analog inverting part of the amp).
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sorry, I feel a bit lame, this has been going on too long. But we REALLY have all the parts packed. Tomorrow we'll have all the PCB's packed..
I promise to post here first when they are in the store. That will get you a jump on the people that read about it later in the Newsletter.
I promise to post here first when they are in the store. That will get you a jump on the people that read about it later in the Newsletter.
So they'll appear in the store soon???I can stop checking it daily - worrying that I've missed them - that they've already sold out????
JK..
graham
Here's a rather nice discussion about "passive preamps" ie a pot in a box...
http://www.diyaudio.com/forums/anal...iometer-passive-preamplifier.html#post3157081
http://www.diyaudio.com/forums/anal...iometer-passive-preamplifier.html#post3157081
Hi there, I'm one of the many (I'm sure) people eagerly waiting to take on this amp project (In my case as an introduction to the hobby) and I'm wondering if the kits are already available in the store.
It's really appreciated that someone is putting the effort to do this. I rather purchase a kit from this cite to support diyaudio
-A
It's really appreciated that someone is putting the effort to do this. I rather purchase a kit from this cite to support diyaudio
-A
We are making progress. 600 PCB's unrelated to the ACA, arrived the other day so we got those packed up too. That should be enough for a year or so! Now, the kits, the heatsinks, the power supplies, and the other stuff are all individually packed and labeled and in big boxes, ready to be shipped to LA and the Order Fulfillment Center. Probably today..
Yesterday I loaded up my handcart and rolled 3 boxes to UPS, then returned later with 2 more. They contained the ACA kits, the ACA drilled and tapped heatsinks, the power supplies, ACA PCB's (the kits have them included), and various other PCB's for the store. Estimated arrival at our shipping fulfillment place is the 28th. Then a couple of days for them to get them stocked. So the first of the month is the best guess..
Is this good idea? ACA SIT
An externally hosted image should be here but it was not working when we last tested it.
The R085 won't qualify as a SIT, but the other problem with these and
most other parts is that their input capacitance won't put up with a 10Kohm
source. In the case of the R085 the frequency response starts to go in
the upper midrange. That is why the AMP CAMP AMP used a fet buffer.
