Apogee Scintilla Signature

The Scintilla is, or was, the second so-called ribbon loudspeaker - after Apogee's debut with the spectacular "Fullrange"- that Apogee released. The pair was offered in the USA in the later 1980s for the astonishingly low price of $3,500. This is a full range dipole magnetostat, designed as a three way system with four(!) approx. 12 mm narrow aluminium tweeter ribbons: two in the front and two in the rear working in phase opposition (!), so that the high frequencies are radiated by a kind of pulsating, slim cylinder. Furthermore, an approx. 45mm wide aluminium midrange ribbon, all five transducers in ONE common, very strong magnetic gap. Both systems consist exclusively of corrugated aluminium foil without Kapton or Mylar foil for reinforcement, the length is about 1350 mm. Due to this construction, these ribbons have an extremely low impedance, which was difficult for most amplifiers of that time, but most importantly, it makes them very light. In contrast to almost all later midrange/tweeter drivers, these ribbons are "single ended", hence the low impedance, but also the excellent sound, because only this design allows to do without the plastic carrier foil, which can bridge the otherwise unavoidable conductor gaps. The entire "diaphragm" here is at the same time the driven conductor, completely free hanging in the magnetic field. The low-mid range was/is reproduced with a foil reinforced "Quasiribbon" as with all other full range "ribbons" Apogees. The traces are meander-shaped, behind the traces is a perforated plate with - hopefully (unfortunately not always the case) - rows of magnets correctly glued in relation to the direction of current flow in the traces. There were two meander cuts: approx. 34 mm wide traces for the famous 1 Ohm version and approx. 16.5mm narrow ones, for a pure 4 Ohm and a version that could be switched from 1 to 4 Ohm. A very early version had a transformer for impedance boosting, but only a few of these were built. It is estimated that about 1000 pairs of Scintillas were made in the USA during Apogee's "lifetime", of which about 40 pairs are said to have been shipped to Germany. The extremely good, highly resolved and at the same time always extremely musical sound is primarily attributed to the mid- and high-bands, especially in the 1 Ohm or the switchable version operated in 1 Ohm. The low 1 Ohm impedance is a problem for all power amplifiers that are designed for higher load resistances (4...8 Ohm) by means of a higher internal operating voltage (over +/-63 Volt DC) and relatively few output transistors, e.g. 4...6 per side. Power amplifiers with lower internal operating voltages (40 to +/-56V DC) and at least 6 or 8 output transistors per channel have no problem with this. The same applies to tube power amplifiers, as long as the output transformers can be switched or soldered to 2 or better 1 Ohm, and there are at least 6, better 8 power end pentodes per side. Especially the tweeter ribbons, but also the wide midrange ribbon of the Scintilla are mechanically VERY sensitive. Incorrect storage, drafts or careless transport movements overstretch the corrugation of these ribbons, so that the elements then sag too far and have to be replaced. As with all Apogee full-range ribbons, the problem with the low-mid ribbon is the edge binding, which is made of a PVC-based foam similar to Tesa-Moll. This crumbles due to plasticizer loss after about 15 years. This damping foam cannot be replaced without destroying the bass foil. A decomposed edge restraint manifests itself in buzzing accompanying noises, which are especially stimulated by upper to middle basses (75/150Hz) and are very disturbing. In the case of a used instrument with original foils or ribbons, it should therefore ALWAYS be assumed that these must be completely replaced. This is possible with restorers in Holland, Switzerland, England, USA and Australia, who install the CNC-manufactured Australian foils from Graz. No cheap pleasure, but this loudspeaker plays, if everything is right, in terms of musicality and finest resolution - but not in sound pressure -, in the league of the current 20- 30T€ class quite in front. Many connoisseurs of the scene are of the opinion that this loudspeaker - especially the 1 Ohm version - was the best Apogee ever built. Just this version has also brought Apogee the reputation of the "Ampkiller", although only this one model in the range had this very low impedance.

Regeneration of a decomposed rim has already been done successfully using very thin, neutral curing silicone rubber. This is then only carefully introduced into the foam from the front and, after curing, at least partially restores the desired properties. The advantage, apart from the considerable cost savings, is that the original foils, which are superior to the replicas in several respects, can be retained, provided they are undamaged.

A serious disadvantage of ALL Apogee full range speakers should not remain unmentioned: the bass foil tends to excite or produce various background noises. These can be: the already mentioned "buzz" caused by defective edge damping of the bass foil, buzzing/rattling caused by too loose upper/lower foil clamps ("upper/lower clamps", relatively easy to remedy). Furthermore by parasitic vibrations e.g. of the front mask or of crossover components (with some effort fixable). Much worse is a wah-wah-like noise (internal designation at Apogee USA), or also called "foil shimmering", which is caused by the bass foil vibrating at certain frequencies, mostly very narrow-band with center frequencies in the range of 200 to 400Hz. The foil no longer oscillates in phase, but parts of the foil move forwards while others oscillate backwards. As this happens with slightly different frequencies due to the constantly changing foil width over the height, beats occur, i.e. cancellations and sometimes amplifications, hence the "flirring" or "wah-wah". This problem is very difficult or impossible to solve, at least with the installed foil. Although this phenomenon can occur strongly with pure sine tones even at the lowest levels (below to at one volt terminal voltage), it is surprisingly and fortunately rather rarely heard with music. If, then usually with longer notes of individually torn strings of acoustic guitar or solo singing. Apogee has been combating this problem quite successfully since the early 90's by using sinusoidal instead of straight horizontal conductor cuts of the bass foil. These foils were used on the Stage, Studio Grand and Grand. Measurements by the author have shown that the Graz foils, which are very well made, are particularly susceptible to this problem. It is suspected that the random irregularities in the more or less wide overlaps of the Kapton carrier film of the original membranes, which is composed of several transverse strips, had a vibration-inhibiting effect. Interestingly, this topic is rarely or never discussed in discussion forums. Only in tests of different Apogees in 1988 in the magazine "Audio Critic" the problem was mentioned by name. Therefore, before buying: be sure to connect a sine wave generator and tune through at low to moderate levels from 30Hz to as high as 10 kHz. Prices: There were times when you could get a used and almost always broken pair of "Scinnies" for 500€/$ or less, but that's gone. Defective ones bring 1000 to 1500€/$, for an overhauled pair 5 to 8T€ and more are to be invested. For an overhaul, 4 to 8T€ should be budgeted, depending on the effort that goes beyond a mere foil replacement, e.g. for a paint job or a rebuild of the complex crossovers. Replacing the bass foils yourself is extremely difficult and will definitely go wrong. Even the experts do not always succeed in this action at the first attempt.

A few more data: Height: approx. 150cm, width bottom 83cm, top 74cm, thickness: 9cm (without base plate); Weight: different specifications: 75 or 90kg/piece; crossover frequencies: various specifications: 500Hz/3kHz and 300Hz/900Hz, slope 6dB per octave; Sensitivity: 79dB/Wm; Impedance: 1 or 4 ohms; Frequency response +-3dB: 25Hz to 20kHz

Note: The author owns several Apogees, including Scintillas, and has written these lines to the best of his knowledge.