Re-Equalizer II: Oh! So That's What They Meant!
The other half of this story is the Re-Equalizer II and what it can do for the record collector. Most casual record collectors don’t have the needed styli (line contact, truncated elliptical, spherical, etc.), cartridges (stereo, mono, high compliance, low compliance), or specialized phono preamps to hear what tens of millions of records should sound like. Played back with a moving-coil, in a high resolution system, a 60-year-old mono LP can sound like a 747 crashing into a light bulb factory. To understand what’s going on, you have to familiarize yourself with the history of the LP, and the disks that came before the LP.
Way before the advent of the LP, almost all disks were cut with varying amounts of bass attenuation that would be corrected when playing back the record. The reason for this was that unattenuated bass would cause the cutter head to cut into adjacent groove walls, destroying the lacquer. The cutter heads were “constant velocity”* devices, meaning that without some kind of EQ, treble grooves would be increasingly tiny and bass grooves would be increasingly large. When the “long playing” record was proposed by Columbia (here in the US), they came up with a playback curve that allowed storing a lot of music on one side, and that minimized the effect of surface defects and wear/tear. On playback, the consumer’s electronics would cut treble and boost bass. Because you are cutting the boosted treble to get it in proper proportion to the bass, you are also reducing the high frequency noise that comes from pressing defects, damage and mistracking. Creating a precedence that would continue to the digital age, RCA proposed a competing EQ curve for its new 45rpm, a curve which RCA based on earlier curves. They had proposed the 45 rpm format that was basically a miniaturized 78 (the LP was something much more radical in approach, which allowed an entire symphony to be recorded on one disk). The result was that the 33rpm LP and the 45rpm EP had different playback curves.
*The difference between constant velocity and constant amplitude can be understood when you think of how fast a stylus must move when playing 20,000 Hz versus 20 Hz. The stylus has to switch directions 1,000 times more often at 20KHz than at 20 Hz, which means the stylus is moving much faster to cut or reproduce treble. Hence the importance placed on low mass styli, cantilevers, iron, coils, etc If a cutter is a constant velocity device, the rate of travel of the cutting stylus must always be the same, whether it is going back and forth at 20 Hz or 20KHz. The consequence is that for a stylus to move as fast at 20 Hz, when compared to 20KHz, the distance traveled by the stylus must be many times larger to keep going the same speed. If the distance traveled by the stylus were to be limited somehow, the stylus would travel slower at low frequencies. This wasn’t possible (the cutting head is not a constant amplitude device), so the only workable solution was to reduce the bass so that the amount of distance traveled by the stylus would be similar to the highs, allowing the cutter to cut more narrow grooves, and the playback stylus to more easily reproduce the signal. If that explanation isn’t that clear, it’s because I’m not a physicist. It took me a long time to understand the difference between constant amplitude and constant velocity.
If it were just two different curves, then there wouldn’t be much of an issue. Unfortunately, when including the various practices going back to the days of Edison, there are over 100 different playback curves used by various record manufacturers. Some kind of standard had to be set so that everyone was on the same page. Though many had legitimate claim to having the “best” curve, only one would be standardized, which happened to be very close to the RCA curve - not hard to understand why if you realize how powerful RCA was at the time. After the RIAA adopted the standard, all equipment manufacturers adopted the new curve into their designs and it would eventually be the only playback curve offered. So what to do with the old records? After the adoption of the RIAA standard, several manufacturers continued to include the various curves, notable examples of which are the McIntosh C8 and Harman-Kardon Citation I. These multi-curve units had many more capacitors, resistors and switches, so they were usually the most expensive preamps offered. Gradually, the multi-curve units died out completely. The solution, for most people, was to hunt down a Citation I, or similar, restore it, and use it for playing back the various odd-ball records in their collection.
One weakness of those older units was that the switching and parts needed to accomplish multiple curves caused poorer performance. Subjecting a tiny signal to dozens of contacts, solder joints and stray capacitances created a lot of noise and distortion. One possible solution, one employed by a number of archivists, is to amplify the signal to line level, but without any EQ at all. The resulting signal is recorded to a digital file where various EQ curves can be applied to find, objectively and subjectively, the best curve for that recording. Well, that all seems like a lot of work for a regular record collector, not to mention that many of us don’t want our precious analog signals sliced and diced and converted to digital, another source of distortion.
The solution from Esoteric Sound, the Re-Equalizer, one that seems to adopt “best practices,” is to apply a corrective filter after your pre-existing phono stage. If your phono stage does an adequate job of doing the RIAA curve, the Re-Equalizer will reshape the signal into various curves by using a set of selectable filters. The result is that you can have audiophile sound from your audiophile pressings, and by flipping a switch, you can play back just about any record by adjusting the knobs on the RE-EQ. The Re-Equalizer sums to mono, which is not a problem for most listeners. However, there are stereo records cut with non-RIAA curves, not to mention that some detail is lost when summing a stereo signal to mono, because the two coils of a stereo cartridge are slightly out of phase with each other, causing the signal to partially smear or cancel out, something a true mono cartridge will not do. Esoteric does offer a price break for people wanting two units for stereo. That would also allow you to select the inside or outside groove of a mono record when using a stereo cartridge, something done by most archivists, who pick the quieter of the two channels, and use it as the basis for their work.
Some Important Info:
Re-Equalizer Features
* Supplied with eleven page manual including recommended compensation settings for any vintage record - including acoustics. This is the most extensively researched chart ever produced.
* In "BYPASS" mode, signal is hard-wired input to output - no compromise to any audiophile unit
* Passive equalization design & film capacitors assure low TIM and transparent sound.
* High input impedance for use with both tube or solid-state amplifier outputs.
* Accurate record compensation from any source using your preamp.
* Connects to hifi systems like any ordinary graphic equalizer.
* Works with phono, tape recorder outputs - any source.
* 8 settings of Turnover and 8 settings of Rolloff.
* Gold-plated RCA connectors.
Playing a record with the wrong EQ is the worst of possible fates, regardless of what an extra box does to the signal, whether it is another set of interconnects, more RCA jacks, solder, wire, PCB, switches, resistors, capacitors, or active devices. The resulting deviation from flatness can be much worse than modern cartridges and speakers. Some records will sound extraordinarily bright, others very dark, and the overtone structure of real instruments will be knocked out of whack. One instrument can be mistaken for a different instrument, details can be rendered inaudible, and relative prominence of a musician in the mix (like a soloist) can be lost. If you are primarily a record collector, what distortions are introduced by the inner workings of the Re-Equalizer are far outweighed by hearing the records played back with the correct equalization. When bypassed (Re-Eq switched out of the circuit), I heard no noise or veiling with the Shure V15iii. When in-circuit, I did hear just a bit of opacity, which is the result of more gain stages, resistors and capacitors. A high-end moving coil’s signal will be slightly compromised, even when the Re-Eq is bypassed, just because of the extra jacks and switch. So, you might look into a second arm/table, or another arm if you have a plinth that allows for it. What route you choose depends on whether you are a collector or an audiophile.
Hearing old vinyl played back correctly for the first time can be revelatory. Many of my mono records are not RIAA, so every record can be an adventure in EQ tweaking. After a while, you get faster at finding the right curve and you become aware of trends from certain labels and even certain countries. One possible solution is to print some address labels and keep track of which settings you preferred (put them on protective outer plastic sleeves). In daily use, I never felt like I was being robbed of information or suffering extra distortion. I was able to hear, for the first time, what the mastering engineer intended on records that had sounded dreadful without compensation. Just remember that it isn’t an exact science. The tapes and transcription disks used to master old vinyl were also subject to EQ errors (both need EQ). The EQ preemphasis introduced in the mastering process could have been poorly implemented (wrong values, bad parts quality and even poor design). Some of the records will be in “the crack,” like the singer who can’t find a key that is comfortable, being somewhere on the piano that doesn’t exist (the crack between two piano keys). Pick whatever sounds most natural, the curve that makes it sound real. That is what a good mastering engineer or archivist would do.
There are buyers who only purchase audiophile reissues, so the Re-Equalizer probably won’t be useful in those systems. It’s a shame to say, but it’s not expensive enough for a lot of audiophiles to take it seriously. Well, you should. The assumption that “if it’s cheap, it must sound cheap” is moronic. I’ve heard $100 moving magnets sound better than $1,500 moving coils. If you buy lots of used vinyl, the money for the RE-EQ is well spent. Maybe we can get a gold plated version for audiophiles, just so they will buy it.
Buy More Records
To give you an idea of what you are missing, I will recount my shellac “road to Damascus.” Thinking all 78 rpm disks sucked and were good only for shooting skeet, a record collector buddy said “why don’t you listen to this one.” This record was BN 543, Thelonious Monk - 'Round Midnight b/w Well, You Needn't, a mint 10” 78 rpm Blue Note from 1947. Yea, verily I say unto thee that I did heareth ambience, the tapping of the foot, and nuance of music, which is the breath of life. No crackle and no hiss to be heard. Get the hence evil noise! The thing which clinchethed the argument was comparing the LP reissue, cutteth from 78 master to 33 lacquer. Verily, I say unto thee, that the extremely expensive LP was much worse than the meek and gentle 78. Hosanna on highest!
I’m very enthusiastic about what both these units can do. The prices aren’t only affordable, they are downright cheap (especially the phono stage). Sound quality, while using both units, was always good and, with the RE-EQ, sometimes better than my reference setup. Summing to mono, then finding the correct EQ, turned some dogs into winners. If you buy lots of used vinyl, especially mono, and if you have a high output cartridge, then you might find a place in your system for both of these units. You certainly can’t complain about the asking price. For people who are interested in exploring and enjoying music, both these components can satisfy, and leave money for more records.
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