Altec 15335a Transformer

**mah** · October 1st, 2010, 10:53 PM

I am thinking of using a pair of 15335a at the input of my DCX2496. Comments please.

Does anyone have a pair they are willing to part with?

Cheers, Marshall.

**bfish** · October 2nd, 2010, 10:50 AM

Hi Marshall,

What happened to your "hook it up and try it" mantra?

Depends on the relative Z (pre out vs DCX in). The 15335 is a 1:1 ratio, meant for ~matching. If your devices are quite different Z, the 15095 might be more appropriate, as it can be a 25:1 (or 1:25) or even 100:1 (or 1:100) depending on how it's wired. Not only would you get the isolation and conversion, you might pick up a bit of voltage gain too (a good thing). You can essentially disregard the xfmr label impedance(s), they're for the convenience of "standard" low Z/high Z values. The ratio is what really matters.

**Panomaniac** · October 2nd, 2010, 11:02 AM

How were you planning to wire them up, Marshall?

**mah** · October 3rd, 2010, 12:08 AM

I have the DCX but I am waiting for the DIY interconnect parts to arrive. I will tailor the length of each connect to reduce the mess of cables behind the gear.

I will try the direct connections to the DCX - just looking at some further options.

The TX would be used in interface #2.3 in this document - gives noise reduction, not gain.
The transformer is 10K to 10K. I thought close enough to Altec 15K to 15K. The 15095 has become more expensive since the moving-coil phono cartridge guys 'discovered' it.

http://www.jensen-transformers.com/an/an003.pdf

Relevant TX details:

JENSEN TRANSFORMERS, INC. - LINE INPUT TRANSFORMERS

I also found this:

NEW! Balanced to Unbalance Conv. Kit - Volt Electronics

Cheers, Marshall.

**Panomaniac** · October 3rd, 2010, 08:45 AM

The analog inputs of the DCX are balanced 20K, so the 1:1 15K transformer will work fine. If you used a 1:2 transformer that would give you a 6dB boost, but at the expense of a 5K ohm input impedance. Your Sony preamp has an output impedance of 3K, IIRC.

Not sure if it will be of any help, but it does not hurt to try. The transformer may give you better sound than going in unbalanced. The Jensen iron is also very nice, if you don't find the Altec.