Is RIAA equalisation enough for Phono Stages?

interesting question. FYI, very few offer this option, far fewer than you suggest. In fact the EAR and Manley don't. The Graham Slee Jazz Club model, Zanden and FM acoustics are the only ones that come to mind.

It's called an equalizer.

People who distain equalizers conveniently forget the RIAA process.

As I have commented before, what vinyl really needs is dynamic equalization, similar to Dolby for mag tape, and actually developed several decades ago by DBX. It not only made vinyl as quiet as CDs, but dramaticly improved cartridge performance by always having the signal near the optimum level. CDs, and corporate greed on the part of DBX who, unlike Dolby labs, would not allow other hardware manufacturers to use their patents, killed it.

ELdartford,

It is not a matter of "conveniently forgetting about the RIAA process." In a high resolution system, additional equalization circuitry, or any other ancillary circuitry for that matter, will definitely represent a degradation. Whether whatever benefit is gained is worth that degradation is a matter of priorities. It seems to me that if one is concerned about the issue, having it built into the phono stage as an alternate routing to the RIAA standard circuit is far superior sonically to having additional EQ either built in or, worse yet, outboard, where it would necessitate another pair of interconnects. If you find yourself getting impatient with this sort of thinking, then by all means, forgo on the finer points of quality in deference to convenience and tonal control.

BTW, I have never found the noise on reel to reel or that of a quality vinyl playback system, assuming high quality records, to be worth the degradation of either DBX or Dolby.

Piedpiper...I agree that unnecessary equalization is a bad idea. Along those lines, I have experimented with a biamplified phono preamp. We (RIAA) go to the trouble of boosting the low frequencies, and then we use a crossover network in our speaker that cuts the lows back down for the signal going to the mid/tweeter. I found that feeding the tweeter with the raw (no RIAA) signal with just a passive filter to roll off the boosted highs gave remarkable clarity. Of course the woofer needs the usual RIAA LF boost. For this approach to work the design of the preamp and the speaker needs to be coordinated, and some provision needs to be made for signals that are flat, Tuner, CD, etc. A good DIY project, but not suitable for the mass market.

As for the tape hiss on pre-Dolby master recordings, you don't need a "high resolution" system for this to be evident, and, IMHO, annoying.

cool idea, for, as you say, DYI.

re: tape hiss: agreed, but a high rez system does help you hear what you're missing, hiss be damned, by using noise reduction. It's possible that listening habits, in terms of volume, may contribute to how annoying hiss ends up being; just a thought. Of course, what gets on one's nerves is very subjective.

If you have many records from 1960 or earlier especially earlier than 1955 on a variety of labels, it would definitely be useful to have alternate EQ options built into the phono preamplification. You could also use the variable options to tweak modern recordings but there might be better ways to do this -- I am not sure. The above poster who cautions us not to confuse phono equalization with what you can do with a good graphic or parametric equalizer makes a good point. Just as you want to approximate the cutting head with your VTA and shape of your stylus, you want to match the phono equalization to what was used when the record was cut. This is separate from how the record/master tape was mixed -- where I'd think a house sound or the mark of a particular recording engineer is created mainly.

It would be interesting to know if any labels did not really standardize on RIAA even though it is so stated on the records and covers. The specific equipment and components used would also contribute to some variation but nothing like what happened during the 78 rpm era -- where tolerances on resisters and such were so much wider than they are today -- or so I have read from folks in the 78-L and ARSCLIST. I have not read the article in HIFI+ but would love to see it if anyone can email me a jpg or pdf.

I just got a Reequalizer unit from Esoteric Sound for 78 and early LP playback and transfer and it is easy to use and does not introduce any obvious noise that I can hear on my system. Going forward, I also hope to try out a phono stage with variable equalization built in. The manual for the Re-equalizer is available for download at www.esotericsound.com and explains the issues of phono eq v. clearly.

Since I have been researching phono stages with variable EQ, I wanted to mention some units which have it in addition to Graham Slee's Jazz Club and Revelation.

Hagerman Bugle Pro around $400, Hagerman Archiver balanced design $999, KAB USA Souvenir around $1200, Eldberg MD 12 MkII around $1200, Millennia LPE-2 $10k, FM Acoustics 222MKIII 18K, and others I am sure.

I know that SimAudio's latest unit has 1 alternate EQ setting for earlier LPs.

This is a specialized product and none of the fully variable eq phono stages are carried by a local dealer. You have to commit to some costs in order to check any of these out. I would love to know others experiences with any variable EQ phono stages. Best, Stephanie

My first phono preamp was a Heathkit, and it had separate switch-selectable "Turnover" and "Rolloff". Damn nuisance!
Standardization was the right idea.

I remember om the old days, Scott, Fisher, McIntosh all had various rolloff configurations. I remember RIAA, AES, FFRR and other indications you can point your control to.

Seems to me the original poster was not talking about historic recordings pre RIAA standardization, but that after the adoption of the RIAA curve some recording companies were stubborn or otherwise got creative with eq. Maybe someone can set the record straigth here, hell maybe even David12 himself if people let him!

I am only reporting the Jist of the HiFi+ article, whether the problem was non adoption of RIAA, or as Steph Gaynor suggests, other aspects of cutting and mastering, I am not sure. It certainly ties in with my experience of DGG, that I never really enjoyed them. Roy Gregory reports finally understanding why Karajan was considered a great conductor, with specific equalisation of his DGG pressings. I claim no great expertise or experience in using different equalisation circuits. I raised the subject, simply to find a general view of it's usefulness in considering a phono stage purchase

It appears that some definitive research is in order as to what different curves would be appropriate for the different eras of the different companies.

EMT had a phono stage at the last CES with many choices on equalization of records. One listen to it suggests that you need more than RIAA. It also works for 78s.

This site http://geocities.com/[email protected]/mixphono.htm has an expalnation of Pre RIAA equalization. If you click on the "Recording curves" and "Record label usages" links at the bottom of the page you will see the various Pre RIAA curves.

Since I have many pre 1955 LPs, I have researched Pre RIAA EQ fairly extensively. I have seen numerous mentions that some Record Labels, particularly European labels, did not switch to RIAA EQ when the standards were adopted in 1954. Some of the articles that I have read say that most, but not all Record Labels had adopted RIAA by the end of the '50s. Some labels, however, did not switch to RIAA until the early '60s (European Decca!). The Record Usage Label table at the above website shows a number of record labels that did not switch to RIAA until much later than 1954. Though that table is not complete. I have a 1960 mono Philips LP that has the treble rolled off at the Pre RIAA slope of 6dB.

As you can see from looking at the EQ tables at the above mentioned website, designing a phono stage that can properly EQ pre RIAA LPs is a complicated task. If you are only concerned about 33 1/3rd LPs, then you need four different setting for restoring the rumble shelf, you need five different settings for bass rolloff frequency, and you need seven different settings for the slope of the treble rolloff. To have this many settings and audiophile quality sound is not a trivial task and it does not come cheap. I have been working with one manufacturer in helping him determine the settings for the Pre RIAA phono stage that he is designing. We have had lengthy discussions regarding the need versus the cost and effort required to add each separate setting.

An audiophile quality phono stage that can handle any Pre RIAA 33 1/3rd LPs is not going to be cheap.

Rgordonpf, and the EMT is not cheap!

The EMT JPA-66 looks absolutely gorgeous. I love their arm and cartridges and would love to hear it.

On a cheaper note, I've got the Sentec EQ-10 tube phonostage coming from the same (US) distributor. It's made in Sweden and allows many variations for mono LPs (and now, it appears, some stereo LPs!) and 78s.

http://www.toneimports.com/sentec/sentec_eq10.html

Patrickamory, Loricraft has an inexpensive phono stage with many choices for equalization. I have not heard it, but had their standard model which was very good for the money.

I had the pleasure of attending one of the HiFi+ demonstrations at the RMAF. They used a Zanden phono stage which has multiple (but not continuously variable) RIAA settings. The table/arm/cartridge combination was kept constant except when demonstrating the utility of a mono cartridge with a mono recording. This was a methodical demonstration with only a single variable changed during each part of the demonstration. Roy Gregory and cohorts are to be commended for taking the time to make this such a meaningful demonstration.

The results were easily heard and for me, justified the cost of the trip. IMO, if you are dedicated to vinyl and have a significant investment in analog, it behooves you to at least consider a phono stage with variable RIAA. I have recently purchased a new turntable (Galibier Stelvio/Triplanar/Dynavector XV1-S combo) and the HiFi+ demo will definitely enter into my thought process as I look for a new phonostage/preamplifier. I have many jazz records recorded prior to 1975 that should benefit. I am also looking into add a second arm with a mono cartridge for my many mono recordings.

Regards and enjoy the music.

Tbg, thanks, but since I've got the Sentec now (and having a great time playing with it), I think I'm set for the moment!

Patrickamory, can you tell us more about the Sentec. I have not heard of it, nor can I google for it.

Hi Tbg, it's an all-tube unit from Sweden with almost 100 curves available, built by a retired (but apparently legendary) audio designer - cut and paste this link:

http://www.toneimports.com/sentec/sentec_eq10.html

So far it's been pretty revelatory on early '50s pressings, including Emarcy jazz, US Columbia classical (mostly pre-6-eye, i.e. blue label), early UK/Germany Decca and EMI mono classical (LXT, ALP, WALP, Furtwangler etc.), and mono French classical (Discophiles Francais). Cool looking to boot. All settings can be made on the fly.

Patrickamory, wow Tone Imports. They also import the EMT JPA-66, which I have heard. It gave a major improvement on the early LPs, such as the early 1950s, and 78s. It probably is more expensive than the Sentec. I just noticed that the Sentec is mono. Do you have two, or do you have a mono dedicated vinyl source?

The Sentec is mono - however it can be used with mono modern cartridges and stereo setups - it has two inputs and two outputs. Via a toggle switch, you can use it for true mono, with the outer groove wall (typically the less damaged one) for preference.

To add to the confusion - what about the Soundsmith Strain Gage?

It doesn't have RIAA at all - but accomplishes it another way. From what I read
it is about 1db off from RIAA, but the results people are getting seem to be great.

When I had the Win strain gage cartridges, I understood why there was no need for RIAA, but I no longer recall this. Does anyone know why? Also, I remember Sao Win demonstrating the Stax CPX cartridge at CES. It was far and away the best vinyl sound I have ever heard for the cut and a half on one side of a LP that it lasted.