16 ohms speakers- 8 ohms output amp

PS:

Fertin specs the EX20 as an 8 ohm driver, so I assume yours are of special order/production.

Not familiar with field coil drivers, so don't know if you measure the static impedance in the same manner as that of later magnet design cone drivers.

I start by measuring drivers (with a multi-meter) to gauge what I'm starting with.

I've owned 16 ohm "marked" Tru-sonic 80FR's, which measured in the 3-13 ohm range.

Only a few pairs of the vintage drivers I've tried measured within 20% of spec.

My current matched pair of 80FR's come in @ just above 7 ohms and the previous pair @ approx. 13 ohms.

I imagine you would have tighter bass than if you had 8 OHM speakers. there is a limit on how high the impedance can be before it is not musical with the result being a dry sound that is too lean. These are observations after using a Speltz autoformer.

I checked the specs and they are 8 ohms. I was reading Dr Gizmo review of the PHY-30 and thought that the Fertin were the same. What can I say... I guess this really solve my problem. Now, those who have Fertin 20ex, what amp are you using and do you need a sub with these. Be kind, I'm just starting in this world of hi-fi and this isn' just a plug and play thing. Thanks.

Try searching Fertin @ audioasylum.com as there are a couple of owners/previous owners mentioned.

You may be able to contact them through the Email system.

If you have a scroll and/or keyhole saw and a drill (to cut the holes) you could first experiment with DIY plywood open baffles.

If you have more sophisticated tools, and know how to use them, then all the better.

It's important to use flat wood and to systematically tighten the drivers to the baffles (like an auto's oil pan/valve cover) as to not bend the driver frames, but other than this it's fairly simple.

I've made experimental OB's from scrap ply, a drill/scroll saw and a wood rasp (to bevel the edges of the holes) and I'm officially lame.

Inexpensive DIY OB's approx. 3' x 4' (and larger if possible) will allow you to judge whether added woofers/subs/HF drivers will be needed.

Securely coupling the drivers to a stiff/thick baffle generally offers a cleaner sound/more pronounced HF's.

The distance from the floor to the driver will also affect the bass/mid-bass.

I have not heard much of a difference between centering/offsetting the drivers, but placing them off center seems to be the preferred method of many.

The above variables are why I suggest cheap/DIY in the beginning.

I second dekay's advice for a good, inexpensive, diy amp. Don;t fret too much over the impedance, tubes have high output impedance (hence the output trannies) and love high impedance loads. Also remember, if you're measuring the Fertins with a conventional multimetre, what you get is the resistance rating Re (dc) -- not impedance Z(ac).

Again, as dk suggests, the baffle will be an important contribution to the sound. Why don't you try out PHY's "panneau plan" -- or Supravox's. They work very well.

As I mentioned in an earlier post, the field coil allows you to play with the drivers' characteristics to suit your tastes. More than most of us with fixed magnets can do!