I often recommend JSE Infinite Slope Model 2's. (see review of Model 1 below)

Recently to someone looking for the 'best' tall floor stander, with a high budget. It could seem like a joke in a high budget search, except they remain uniquely remarkable.

IF I wanted a pair now, I would plan on having my Woodworker clad them with a very nice select veneer, that would kick them up a big notch.


Jeff Joseph, Joseph Audio) was a salesman at Harvey's during the short time Harvey's sold the JSE's (see below) (I never met Jeff until he had his own company, just as a customer talking to him). Check the technical specifications: he still uses the Infinite Slope Crossover in several of his designs. He has superior cabinetry, designs, deserves the high praise of his products.

IOW, the results of the crossover was and remains remarkable, a very large part of my continued recommendation.


Model 2's 4 way were JSE's top of the line model. Big response at NYC Trade Show.

Harvey's premier audio store NYC featured them, huge and instant success. My friend Wayne at Harvey's told me when they arrived there.

UNTIL: they repeatedly failed to meet delivery promises. 

Wayne told me, they were making the enclosures themselves, the biggest mistake they ever made. Harvey's customers quite angry, Harvey's dropped the line.

Thus Very Few people heard or were aware of them (even though great reviews were published).

Only speakers I heard in a trade show that I instantly wanted. 

Got lucky, my friend Phil at Leonard Radio had taken a pair in trade, with burnt tweeters. Leonard's owed me a favor and sold them to me for $700. Replaced the Dynaudio D21 Tweeters myself.

Frequency Response, Imaging, Totally Involving. Everyone loved their sound here.

Front Panel 2 layers 3/4" MDF: 1-1/2" thick. Tall (tweeters high)Sloped fronts (theory of time alignment, and alters the angle of dispersion of direct and indirect sound waves off the floor and ceiling; 

Heavy on 4 dual wheel furniture casters. Dual wheel caster's axels do not wobble like single axel's do). (I changed to 3 casters: more weight per wheel and 3 legs or wheels find level anywhere you move them). 

I tried spikes, no advantage, went back to wheels, big advantage for alternate placement and alternate toe in. (setup for 1 centered listener; alternate toe-in for two listeners, each off center).


review of Smaller Model 1 (very positive reviews of Model 2, but cannot find any).

Clarifies the two unique patents (see also photo of technical sheet).

1. Infinite Slope Crossover 80 and 100db/octave
2. Bass Phase Shift (using 10" and 12" woofers uniquely for extended bass

The two Patents belong to Richard Modafferi

Richard Modafferi, inventor and independent consultant to AudioClassics, has established himself as one of the world's foremost authorities on tuner & loudspeaker design and development. He holds Masters degrees in Electrical Engineering and Computer Science from the NJ Institute of Technology. A Senior Engineer at McIntosh Laboratories from 1968-74, he designed the MR77 and MR78 tuners and the famous "Rimo" filter. The MR78 tuner has received world wide acclaim for its State of the Art performance. From 1974 to the present, Richard has been a self employed inventor at Modafferi Acoustical Systems, Inc. He has been granted a United States patent for Phase Shift Bass Loading and for the Infinite Slope Crossover. Richard also serves as a writer, reviewer and test lab for Audio, Audio Critic, The Sensible Sound.


I designed/had built Rosewood Enclosures for my Vintage 4 way horns/15" woofer (in my main system now and forever!. (had help from Electro-Voice Engineers, still in NYC at that time). Super efficient, 16 ohm so I could use my Vintage 30 wpc mono tube amps with 16 ohm taps..

I gave the JSE's to my son, too big for his wife: he gave them to a friend, they sound absolutely terrific in a large space in the old Firehouse he bought and lives in. He instantly bought a 2nd pair.


The D21 Tweeters were famous for burnt coils. Every party my teenage son had, I checked the tweeters next morning. Pair of D21's were $60. back then, he paid.

I switched to Vifa Tweeters, never burnt out, my friend changed to SEAS (John Sollecito's choice).



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    Comments 12

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    My buddy from Baltimore...also a JSE 2 owner...just texted me that a friend of his bought a refurbished pair for $1200 from Lawrence, Mass. Gotta be the ones you suggested in this thread...yes? Refoamed woofers and new tweeters.


    Hi again,

    Have you heard your friend's pair with the SEAS tweeters? Or the Morel's?

    If so...what were your impressions?

    Have you read any owner comments about replacement drivers vs the original Dynaudio's?

    A few years ago, a friend of mine's four woofers needed refaoming. Instead of going that route, John S provided him with replacements that he (John) said were better.

    When mine needed repair/replacement, I reached out to John (no response) and then to the company with which he's now associated. They contacted him and also got no reply. My takeaway: the JSE's are old and he no longer can or wants to be involved with repairs.

    BTW: he told my buddy that, were he to build them again, they would go for over $20,000.


    Thanks, Elliott!  Coincidentally...I have Morel speakers in my car after-market system.


    BTW: I have a Velodyne sub paired with my JSE's. My current listening space is small and naively supports nothing below 40Hz so the sub gives them some extra weight and depth.

    An audiophile buddy uses a Klipsch sub, also with good results.


    Hi Elliott,

    Hope 2024 has been good to you, so far.

    As you may remember from our previous exchanges (started on dpreview), I still on a pair of JSE 2's and love them. I had the woofers refoamed a couple of years back by a guy in PA who was familiar with them.

    For future reference...I see you've mentioned Vifa and SEAS tweeters as possib le replacements.

    What's the difference between them and difference compared to the original tweeters?

    Can they just be dropped into the JSE's directly and work with John's original crossover?