Aleph 2 turn-on thump

TwangBar · 23rd October 2006, 04:26 PM

I am going active with my system and will be using my Aleph 2s for the Mid/tweeter section.

The concern I have is that the turn-on thump may cause my ATC mid some harm. Mr. Pass states that the Alephs have a volt or so that causes it (see link).

Nelson Pass comment re: turn-on thump

I also know that a cap on the reference zener can cause more of a thump which I do have on my boards.

My question is: Is there a simple solution to protect my mid or am I worrying too much?

Thanks for any help you can provide.

~Scott

GRollins · 23rd October 2006, 09:44 PM

For a midrange unit, I wouldn't worry too much.
(Tweeters are another matter.)
If it's a problem, put a fairly large value cap in series with the driver; something large enough that the cutoff will be several octaves below the nominal range of the mid. If you're still worried, you can fuse the driver.
I use modified Aleph 2s to drive my midranges (Bohlender-Graebner RD-75s). I run them straight in.

Grey

TwangBar · 23rd October 2006, 11:18 PM

Thanks for the reply Grey.

I think I will use a large (~100uf) cap just to be safe. Easier than messing with my amp.

23rd October 2006, 04:26 PM	#1
TwangBar diyAudio Member Join Date: Jan 2003 Location: Ottawa, Canada	Aleph 2 turn-on thump I am going active with my system and will be using my Aleph 2s for the Mid/tweeter section. The concern I have is that the turn-on thump may cause my ATC mid some harm. Mr. Pass states that the Alephs have a volt or so that causes it (see link). Nelson Pass comment re: turn-on thump I also know that a cap on the reference zener can cause more of a thump which I do have on my boards. My question is: Is there a simple solution to protect my mid or am I worrying too much? Thanks for any help you can provide. ~Scott

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23rd October 2006, 09:44 PM	#2
GRollins diyAudio Member Join Date: Feb 2001 Location: Columbia, SC	For a midrange unit, I wouldn't worry too much. (Tweeters are another matter.) If it's a problem, put a fairly large value cap in series with the driver; something large enough that the cutoff will be several octaves below the nominal range of the mid. If you're still worried, you can fuse the driver. I use modified Aleph 2s to drive my midranges (Bohlender-Graebner RD-75s). I run them straight in. Grey

23rd October 2006, 11:18 PM	#3
TwangBar diyAudio Member Join Date: Jan 2003 Location: Ottawa, Canada	Thanks for the reply Grey. I think I will use a large (~100uf) cap just to be safe. Easier than messing with my amp.