AR-1W - Janszen 1-30 Combination

[geophysicist]

Hello all,

Long timer lurker, first time poster. Anyway, I recently decided to track down the components to build a late 1950s "TOTL" mono system, and in my mind there was only one speaker system that could perform to that level: the Janszen 1-30 with an AR-1W woofer. This seemed to be the combination that set the standard in high fidelity reproduction for at least a 10 to 15 year period, starting about 1956.

I already had the Janszen 1-30, a fairly early model with the voltage doubler bias supply. I'm nearly done restoring that. Thankfully all of my panels were already working well, so it is really a matter of recapping, replacing the rectifiers, repairing a damaged coil, and dealing with the cabinet.

The AR-1W I had to track down from eBay. I found one that was sold in decent, working shape (but cosmetically rough) so hopefully it arrives working and I can go from there with the cosmetic restoration. It is Serial #8266, and it appears from the photographs on the listing that it may have an orange surround. Can anyone hazard a guess as to when it was built?

I have a few questions regarding this combination. Would I be better off bi-amping, or running both off a four ohm tap on a tube amp? What is the approximate sensitivity of the woofer, and will I be OK with 40 to 60 clean RMS watts of tube power driving them? I'm fleshing out a schematic for an amplifier using triode strapped 6AR6s, swung hard into class AB2. My simulations in LTSpice show I should be able to get 60 clean watts from the pair, but with actual iron on the bench, 40-50 watts seems to be more likely before the IM distortion begins to run away. The damping factor is low, being triode strapped, so that should help keep the woofer clean down to its lower limit.

Any comments, concerns, or advice on my little pet project would be much appreciated.

Warmest regards,

Benjamin

[JeffS]

Benjamin,

Welcome to CSP,

I set up a similar system a few years ago, containing an AR-1W and Janszen 65 (half of a 130). The panels worked OK, but the woofer needed resealing and I didn't want to remove the grill cloth to reseal it so I left it alone. That 1W had a woofer with a pleated surround, and they usually need a coat of Roy's sealant to get the bass response back to spec.

You're AR-1W has the half-round surround and shouldn't need resealing. Up until last year, I had another 1W with a half round surround and it had noticeably stronger output than my pleated surround unit. I found your 1W on eBay and noticed that the seller had a tech run a frequency sweep from 30Hz - 1kHz with good results so you should be good to go.

Serial #8266 was likely assembled in the summer or fall of 1957. One way to date an AR-1 is to look for the date stamp on the Altec 755a. Data from eBay that I've compiled shows that serial #'s 7713 and 7845 had date stamps of July 1957. Serial # 11661 was sold with it's original sales literature and warranty card with a date, written by the owner, of Sept 1958. Yours falls on the early side of that date range. Also, AR-1W with serial # 8239 had a woofer with the orange cloth surround which is consistent with yours.

As for the power requirements, 40 to 60 watts should be plenty in a moderately sized room. My son has a system that uses a restored Harman Kardon Citation II tube amplifier (60W/ch) to drive an early pair of AR-3's (which likely have the same sensitivity as your AR-1W at the 4 ohm setting). Keep in mind that I'm comparing stereo to mono, with two 60W channels here, but to my ears, that system has plenty of power.

Follow the instructions on the label regarding placement. I think you'll be impressed with the bass output of your AR-1W. Since your speaker is near 63 years old, remember to apply power cautiously at first to make sure the glue holding the surround and the spider to the frame is still intact. Then sit back and enjoy!

 

 

[rl1856]

A single Dynaco MK-2 or MK-3 would be a near perfect pairing for your speaker and intended use.   MAC 60 or EICO HF50/60 may be better, but are considerably more expensive.  A Dynaco MK-2 or 3 is relatively cheap, and easy to restore.  It will deliver 50-60w of clean power, and is the amp used by AR for demonstration of the AR1, AR1W and AR3.

 

One of these days Ill get around to restoring my Janszen Z400 and Z350 speakers....Each is a 10inch woofers with a pr of electrostatic panels.

 

Good Luck.