Watkins woofers- what's so special about them?

I'm fortunate to live 15 miles from Mr. Watkins store. I've never had the pleasure to hear a pair of the large infinity's, but I have had several pair of Watkins roll thru my collection the past couple of years. I currently have one older pair of Watkins WS-1's that have the dual vc 12" driver and have the walnut cab signed by Mr. Watkins himself. The surrounds need to be refoamed and haven't had time to get to them yet. I also have a slightly newer pair that are in perfect working order and nice cabinets but no label on the backs to verify model #. I'll try to get some pics up later this week.
 
You don't see these often but I recall seeing and ad or writeup in some literature
I have.
If I can find it I will can and post it.
 
Sounds nice, think they are the forefather to the IRS. Should I post pics?

hello cerwinbob, yes please, you should definitily post some pics because there are only a few to find in the net. :thmbsp: i would be very happy to get some photos of these amazing speakers and i think many other people here in AK would agree.

Greetings from the Mosel river region in Germany

Picky
 
Hi Guys

Here are some pictures I took after I finished work. Hope they will satisfy.
 

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The room is not up to dimension and the amplifiers are as follow.

Bas: Dynamic Precision NO1
Upper: Xindak monoblock
Preamplifier: M.F. HTP
Origninal but upgraded active crossover.
 
Just clearing up a mis-conception...

The 12" Watkins woofers in my Infinity Quantum 2's produce profoundly deep bass. Not only does the bass go very low, it's also very clean and tight. To get the most out of them requires an amp that can supply the current they need, and the amp must be capable of driving < 2ohm loads.

The voice coils are 2 ohm and 4 ohm.
From:

https://groups.google.com/forum/?hl=en#!topic/rec.audio.opinion/pG2grJ5bqe8

"Bill Watkins
6/28/00
In article <06795498...@usw-ex0104-033.remarq.com>, tony_...@email.com
says...


>bill, i guess the 'short course' here is that your dual-drive
>system lowered the impedance of the woofer around fundamental
>resonance, making it easier for amplifiers to power the woofer
>at and below resonance. yes?


The benefits of the dual-drive are mainly:
1. Extended bass, higher efficiency, smaller enclosure,
or a combination of the above.
2. In any case, a flatter impedance, and almost purely resistive
load in the bass. For example, one can achieve 6 ohms
+/- .5 ohm easily from 10 Hz through 200 Hz if desired.
The typical woofer would vary from 6 to 20 ohms or so.
Thus the dual-drive removes the highly inductive load
of ordinary woofers in the region of resonance and allows
the amplifier to deliver more power into the woofer."

Also:

"Bill Watkins
6/27/00
In article <5PU55.5406$Sn2....@news-server.bigpond.net.au>,
tre...@rageaudio.com.au says...


>Even one of RAO's favourite sons (Bill Watkins) in collaboration
>with Infinity, released some of the most diabolical speakers
>ever let loose on the domestic market (impedance-wise).
>Trevor Wilson
>www.rageaudio.com.au

---

Trevor, I believe it's time I explained what happened
here. My dual-drive woofer works so:
A second voice coil (vc-2) is wound over the main voice
coil (vc-1) in the woofer, this second coil having a
single layer and very low impedance. Now vc-2 would
normally have an impedance too low for safe operation.
However around fundamental resonance the impedance of
_any_ coil will ~triple. Now we activate vc-2 _ONLY_
in the region of fundamental resonance (around 45 Hz)
and it rises to ~8 ohms or so (being ~2.5 in the
first place) which is safe. This is accomplished with
an LC circuit tuned to 45 HZ and with the Q of the LC
circuit adjusted to provide the response shape and
impedance desired. Please note that the exact value
of vc-2 and the characteristics of the LC circuit give
_COMPLETE_ control of the impedance. The benefit of
the dual-drive may then be taken in extended bass or
higher efficiency in a given size box, or a smaller
box for a given efficiency or bass extension.

Now I set the parameters of the original QLS-1 in a
prototype and shipped it to Infinity. It had a minimum
impedance of 3.2 ohms, acceptable for a 4 ohm speaker.
At that time we were operating a retail store selling
Infinity. Our first shipment of the QLS-1's arrived,
we tested a pair and found the impedance to be
~1 3/4 ohms from ~50 - 80 HZ. Now, the fun begins...
Mr. Nudell wanted a spec down to 20 HZ, he got to
18, as I recall, by adding ~35 grams of mass under
the dust cap, _BUT_ he did not re-tune LC to the
lower resonant frequency, leaving vc-2 operating
somewhat above the new fundamental resonance, and
creating a low impedance in that area. My name
was already on the royalty agreement, which had no
stipulation to cover such... I did voice my
disapproval to no avail.

If you check, you will find our WE-1, built and
marketed by _my_ company had no impedance problems,
and neither did thousands of other speakers we
built have any impedance problems. Perhaps this
makes things clear for the technical people here.

Bill Watkins"

So, just to clarify, the 2 ohm coil should never be seen as a 2 ohm load by the amplifier in a properly adjusted Watkins woofer system. It was, however seen as such in at least one Infinity speaker, due to their mis-understanding the way the Watkins interacts with the system resonance.
 
4343 said:
:cool: Just clearing up a mis-conception...

You quoted the following post of mine under the above heading.

mark B said:
The 12" Watkins woofers in my Infinity Quantum 2's produce profoundly deep bass. Not only does the bass go very low, it's also very clean and tight. To get the most out of them requires an amp that can supply the current they need, and the amp must be capable of driving < 2ohm loads.

The voice coils are 2 ohm and 4 ohm.

What mis-conception are you supposedly clearing up?
 
^^^^^^^^^^^^^^^^^^^^
My QLS-1's don't seem to tax any of my amplifiers.
I do notice they can suck up the jiuce.
The QLS-1 brochure from Infinty de Classics tries to explain the even impedance curve of the low frequencies.
Supposedly operates around 5 ohms if I'm reading this correctly.

http://www.infinity-classics.de/mod...antum-Line-Source-QLS-1/QLS_1_Brochure_06.jpg

http://www.infinity-classics.de/mod...antum-Line-Source-QLS-1/QLS_1_Brochure_05.jpg
Are you using only tube amps with your QLS-1's?
 
You quoted the following post of mine under the above heading.



What mis-conception are you supposedly clearing up?

I believe he is showing that the QLS 1 where modified by Mr. Nudell to achieve 18HZ
but the LC circuit was not modified to make the impedance to be in the 3 to 4
ohm range as it was designed to be by Mr Watkins it ended up being less than 2 ohms.
 
Deli Hail,
Watkins developed his woofer to obtain a truly flat frequency response, free of an enclosure resonance peak, by using two voice coils of different sizes, each having it's own impedance and each responsive at different frequencies. So, the Watkins woofer creates high sound pressure levels of flat frequency response along with high efficiency from the same speaker. It also eliminates the reproduction of the enclosure resonant peak which would distort bass response.

Vito

P.S. I have the white paper on these if you would like a copy, PM me your email and I will send you a copy.

P.P.S. Unparralled true bass. LOW, LOW, true bass without rolloff. Knocks your socks off
Tried to send you a pm, your inbox is full.
 
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