Vintage HiFi Audio Forum

Audio Discussion => DIY => Topic started by: rgpit on January 25, 2010, 09:27:12 PM

Title: Speaker level to line level converter box
Post by: rgpit on January 25, 2010, 09:27:12 PM

This is really a daughter project to my cylinder sub woofers project.

My integrated amp doesn't have a preamp output so I need to make a speaker level to line level converter box. I have been told that this is actually a preferred way to add a sub as opposed to using a preamp output. I don't know if that is true or if it really matters but what the hell!

Bought the following parts from Parts Express.
 2 chassis mount RCA jacks
 2 Dual 5-way binding posts
 2 10k Ohm 1Watt resistors
 2 1k Ohm 1Watt resistors
 1 small steel enclosure with rubber feet

That's it,short and sweet. I'll post a couple of pictures when it's built.

Ron

Title: Re: Speaker level to line level converter box
Post by: MasterBlaster on January 25, 2010, 10:45:24 PM

cool, look forward to it Ron.

Whats the power output of your receiver btw?

Title: Re: Speaker level to line level converter box
Post by: rgpit on January 26, 2010, 09:47:38 AM

Main Speakers are powered by a 38Wpc KT88 based tube amp. PrimaLuna Dialgue Two

Title: Re: Speaker level to line level converter box
Post by: rgpit on January 27, 2010, 05:36:37 PM

Here is the finished converter. Nuthin' special, but it works.

Title: Re: Speaker level to line level converter box
Post by: BrianT on January 27, 2010, 05:52:28 PM

Quote from: rgpit on January 27, 2010, 05:36:37 PM

Here is the finished converter. Nuthin' special, but it works.

Looks good

Title: Re: Speaker level to line level converter box
Post by: BB3 on January 27, 2010, 06:26:55 PM

Jesus Christ Ron Is That Impressive. I Sure Wish That I Had Your Knowledge And Skills.

Excellent Work Ron. Oh ! And Did I Mention How Impressive It Is ???? WOW !

Take Care Ron.---------BILL(BB3)

Title: Re: Speaker level to line level converter box
Post by: Kingman on January 27, 2010, 07:40:51 PM

Is this a version of the Carver Z-1 coupler???

Title: Re: Speaker level to line level converter box
Post by: rgpit on January 27, 2010, 08:13:35 PM

Quote from: Kingman on January 27, 2010, 07:40:51 PM

Is this a version of the Carver Z-1 coupler???

Not sure what the Z-1 is. Here is the circuit that I used. It is a simple 10:1 voltage divider circuit.

Title: Re: Speaker level to line level converter box
Post by: MasterBlaster on January 27, 2010, 08:19:14 PM

Ron,

Just curious...
The schematic calls for 10k and 1k resistors.
Why'd you use 100k and 10k?

I would expect that would seriously lower the output levels.

/Al

Title: Re: Speaker level to line level converter box
Post by: rgpit on January 27, 2010, 08:27:18 PM

Quote from: Master Blaster on January 27, 2010, 08:19:14 PM

Ron,

Just curious...
The schematic calls for 10k and 1k resistors.
Why'd you use 100k and 10k?

I would expect that would seriously lower the output levels.

/Al

Oops!...good eye Al. That was a typo. I actually used 10k and 1k.  (I edited the original post and put in the correct values)