Having built both the B1 and ACA, I'm of the opinion that they are not as good a match as being implied above. The ACA really needs a preamp with gain, and especially so for symphonic music and earlier recordings of say, Pink Floyd. My speakers are 94dB, which is above average sensitivity, btw.
Urged on by a friend, I then built the AKSA Lender preamp with 15dB gain. Wow, what a difference? The ACA came alive and sounds much better than it did with the B1.
I'm not knocking the B1. It's a great preamp/buffer. It has to be - it's a Pass design. But it's just not a good match for the ACA which needs a preamp with gain.
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Well said.
Gain(number) = Vout divided by Vin.
Should have started there in my explanation.
You know, when you read this stuff over and over some of it starts to make sense.
I think...
You know, when you read this stuff over and over some of it starts to make sense.
I think...
That’s a good thing. I know it may seem like I am being picky about how terms are used but it makes it much harder for the inexperiened to learn when basic concepts are not presented in a standard way.
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Greetings,
I just ordered a complete ACA Kit. I plan on using it to drive my Klipsch Cornwalls 102db/w they are Crites modified series 2. I will also be using my Carver C1 preamp to start with, I modified years ago, very clean. I'm NASA Certified solder tech. I have built speakers for decades. I just wanted to say Hi.
I just ordered a complete ACA Kit. I plan on using it to drive my Klipsch Cornwalls 102db/w they are Crites modified series 2. I will also be using my Carver C1 preamp to start with, I modified years ago, very clean. I'm NASA Certified solder tech. I have built speakers for decades. I just wanted to say Hi.
Welcome kd7vw, it should work very well with your Cornwalls. I use my ACA with Klipsch FORTE III (99db sensitivity) loudspeakers. I am very pleased with the combination.
kd7vw - That will sound wonderful. I have a 30 year old pair of Cornwalls being driving by an ACA (with a bottlehead Smash as a preamp) - the combination is excellent.
I've preordered a Whammy to use as a preamp (and headphone amp) partly to see how it works out and partly to enjoy the build.
Rich
I've preordered a Whammy to use as a preamp (and headphone amp) partly to see how it works out and partly to enjoy the build.
Rich
Hi Rafa, any news on the WHAMMY as a pre for ACA? I might order a WHAMMY kit if it's a good match. What is the gain of the WHAMMY as a pre amp?I'm one chassis away of testing the WHAMMY headphone amplifier modified to have a line out to be a PRE for my ACA.
Other than that, I know very little of DIY, I'm very new to this.
I did purchase a Schiit Magni and it does a decent job at high gain. In low gain I found I was almost requiring to keep it a full volume. Its $99 so I thought it won't hurt to give it a try.
I'll report further on the WHAMMY as a PRE, hopefully by the end of this week, or sooner if I get a bit irresponsible with work
Rafa.
I'll answer but take this with a pinch of salt... my Whammy is 2 days old!!
Fast answer: Perfect Match!
For my setup, just exactly what I wanted. Built mostly with the kit parts and exactly as per the recommended BOM, the Whammy has 14dB of gain. For my setup, this yields perfect volume at 12 o'clock, and nice margin up and and down for whatever needs.
Sound is superb!
Now... after I finished my cable soldering, Wayne has gone on record saying he would put 20 to 100 Ohm resistors in series with the pre output to prevent oscillation.
I have not done that, have no way to measure if that oscillation is present (nor would I know how to 'detect it'), and I don't know if that would change the gain with the pre output.
So, still a bit early to give a final 'green light' all the way... but it is working beautifully!!!
I did use a different OpAmp and I am planning on doing some tests with other OpAmps, but I'll record all this in the Whammy thread.
So, for about $200, I couldn't be happier. And since I had all from the ACA chassis, the chassis cost me $10 of cutting and folding the pieces.
I'll post pictures on he Whammy soon.
Best regards,
Rafa.
Fast answer: Perfect Match!
For my setup, just exactly what I wanted. Built mostly with the kit parts and exactly as per the recommended BOM, the Whammy has 14dB of gain. For my setup, this yields perfect volume at 12 o'clock, and nice margin up and and down for whatever needs.
Sound is superb!
Now... after I finished my cable soldering, Wayne has gone on record saying he would put 20 to 100 Ohm resistors in series with the pre output to prevent oscillation.
I have not done that, have no way to measure if that oscillation is present (nor would I know how to 'detect it'), and I don't know if that would change the gain with the pre output.
So, still a bit early to give a final 'green light' all the way... but it is working beautifully!!!
I did use a different OpAmp and I am planning on doing some tests with other OpAmps, but I'll record all this in the Whammy thread.
So, for about $200, I couldn't be happier. And since I had all from the ACA chassis, the chassis cost me $10 of cutting and folding the pieces.
I'll post pictures on he Whammy soon.
Best regards,
Rafa.