McCormack ALD-1 question


What exactly is happening in the active mode compared to the passive mode on a McCormack ALD-1? Active what? thanks in advance
ericthered
I am responding planning on getting ripped because I don't know all exactly. But at least if I do say something, and write an erroneous post, maybe someone will feel compelled to respond to your question and straighted me out. Sort of unclog things. This is the desired result.

My understanding is there are two stages active and passive. In passive there is regular?? and buffered mode. Active first.

In the active mode, the pre ads a little gain to the incoming signal (sort of boosts it some) before it sends it on its way to the amp. Similar to the booster signal in a phono stage, and much needed to amplify the signal picked up by a phono cartridge. Without the boost (added gain) from the phono, you would not hear much. With the ALD, it just starts with a stronger signal (from the CD player, say) and ads less boost. This should be louder than the passive mode, and maybe a little different sound. Here's why,

The passive stage, in contrast, ads no gain. That gain signal can sometimes color sound and as such, the passive mode it is the pure way to go. It takes the incoming signal, ads nothing, and sends it on its way. Neutral and passive.

The buffered option (only available to the passive section) is. . . I don't know. Most say they can't tell a difference between the passive buffered, and the passive unbuffered. I ran my TLC-1 for a long time (same passive stage as your ALD) w/o even ever knowing which I was in (buffered/unbuffered). Now I hope I'm right, but if I'm wrong, let it rip.
Chris
The ALD-1 is a "conventional" preamp, meaning that it has an active gain stage with about +12dB of gain. It is unconventional in that it also has both buffered and unbuffered input paths, buffered tape output, a completely passive (no active gain circuit at all) output path, and balanced outputs (active only). So, to answer your specific question, when you listen through the passive outputs, the signal comes directly from the volume control (literally a straight-wire path). When you listen through the active outputs, the signal is being fed from the volume control into a gain stage that amplifies the signal before it is fed to the output jacks - which is typical of most preamp designs. There are strengths and weaknesses in both systems (active and passive), but most preamps offer one style or the other - the ALD-1 is one of the few designs offering both in the same package.

I hope this has answered your question. If you need more information, please contact me directly at SMcAudio@pacbell.net

Steve McCormack, designer
McCormack Audio Corp.
SMc Audio
WOW! I thought I might draw out an answer or two, but never in my wildest imagination did I think I could pull that off! That's just like hearing from Elvis or something, only different. One more reason in an already long list explaining why I am a fan of McCormack Audio (even if I don't know how it works). Thanks Steve.
Thanks for the response Steve-it's a great pre-amp and I also own the DNA-1 deluxe (bought from Chstob when he went multi-channel) which I think is a fantastic amp.