Sound maximizer

[JayDC]

I thought a maximizer was more of a multiband compressor, limiter, and spacial expander.. in one unit..

[leo gonzalez]

That's what Al Grundy told me. Straight from his lips to my ears. I was video taping the session. I can post the video clip with him saying this. Debate it with him. Neumann was not involved in the developement of the RIAA EQ Curve. And a lot of other cutterheads at the time had their resonant frequency much higher.

first, thanks for bringing this up, i remember having a similar conversation with al on this and i remember him saying that too.

when i wrote, i wasn't thinking on them in terms of being directly related in the way you are prob thinking i was. one could see similarities around the way they work and complement each other in relation to compensate over the different limitations of disk cutting.

but let me be clear that i DONT see the riaa filter to be a determinant factor for which westrex neumann or ortofon heads would not work or so! And vice versa! let's not add to the overall confusion! certainly the riaa filter accomplishes something that otherwise these heads could not and with prob no reason to do so. (slowing lows while accelerating highs to meet the riaa expectations).

here is something to dissipate some of the heat this topic has gathered!

http://www.youtube.com/watch?v=K7luMp6lb9M

[leo gonzalez]

i refuse to play these feedback head riaa mind games!

[JayDC]

rigth, coz my presto 1-c resonates at like 500-600, and i still cut a dam fine record..

isn't the riaa filter there just to allow music to actually fit on a record?..

low end is very large w/o it..

and it needed to be a standard so it sound correct on playback
if everyone used different curves stuff would never make sense.. do to playback preamps... unless you don't care and use it to your advantage, which is how i am.. my curve is not 100% to riaa specs, which i am totally fine wit.. people go nuts when i play my acetates... they are that good..

no and then.........lol, tat shit is funny

[opcode66]

Transcript from one of the video clips I want to post.

Al Grundy: "There is a high frequency boost in the record characteristic. And it puts in a appoximately 14db boost at 10Kc and it continues to rise as you go above 10. And there is a ratio of about 20 to 1. So, there is about 20 times more power delivered to the head at 10Kc then there is at 1Kc. And, that's a lot. That is an enormous amount. Why is it there? Well, it's there because one simple answer is tradition. It's always been there so that's why it's there. Why is it 14db or so? Well, that was decided on essentially by RCA when they introduced the 7" doughnut record in 1949 or so. And they introduced that recording curve and they called it the New Ortophonic recording curve. There was an old ortophonic in the days of acoustical recording. So, the new ortophonic was electrical. Of course there were electrical recordings before 49. They started in 1925 with Maxfield and Harrison at Bell Labs. Anyhow the most important factor in all that is the 1949. The curve was based on the characteristics of the music of 1949. None of your were there. I was there. (Room laughs). Big bands were dead in 1949. At the end of the war they disbanded, fell apart. A lot of them regrouped. But, anyhow, the dominant feature of pop recordings at that time was the vocalist. Frank Sinatra, Dina Shore, blah blah blah. So, the orchestra was set up in the usual way. The drums were about 6 or 8 feet in back. The mic was up front for the vocalist to sing. And, they made records. So, the labels read Dina Shore and orchestra. But, the important is that the material, the musical material, from the drums such as snares and cymbals and so on as I said were about 6 or 8 feet from the microphone. So, it was about 20db below the zero level of the vocalist. The high end. Everything above 10kc was about 20db down from the level of the vocalist. Which is you know centered in the 1kc range (I mean that high for male vocalists, etc). So, what happened then was they took something that was 20 db down and raised it 14db by the boost and it still was below the level of the prime signal in the vocal. So, it was a perfectly workable system, workable situation. Millions of records were cut and sold. Blah blah blah."

Infered also in this the fact that the kick drums were much louder than the vocal and thus needed to be brought down a bit. Thus the cut in the low end.

It is my understanding (though I may be wrong) that RIAA also helps to maintain the sound of the highs in the inner diameter as they start to get degraded by inner diameter loss. Sort of like how Presto made a huge variable resistor that tracked the cutterhead as it traveled the diamter and boosted the highs as it got closer to the center.

Al went on to tell a funny story how at the AES during one of the disc cutting sessions it was suggested that they should just phase out the RIAA curve. And, that if they dropped it by 1db a year no one would notice. Because poeple play records 50 times in the first week, 20 time after the second, 10 times in the following months and never play it again after a year. So, if they kept lowering it every year, no one would notice. Funny.

[JayDC]

ok.. makes total sense now... ty opticode...

i tink i'm using a 500C-16, or someting close to it.. since until today i never knew it existed.. i guess some of my ideas and achievements are not new...

[opcode66]

I believe it is dbm actually. I have video of Al explaining how the VU meter works and what the standard was/is. He drew a schematic with an impedance and load. I used a device that my friend has which one of its functions is to calibrate meters. It just said db. Sorry for my not being more specific. Al tosses "db" around like it is commonly known among cutters, and I think it is (can be assumed what I meant). Look at the transcript. Not once did he specify in the entire two days I was there dbm/dbu/dbv. But, of course, I am put under more scrutiny than others.

Yes, call me defensive. That is fair when three trolls are jumping on my every word. Waiting to put me on trial. Who absolutely can't wait to tell me I'm wrong. Yes, I'm defensive, that's fair. I can see how it would come off like that if you ignore the fact that there are three trolls who sit waiting strike anytime I make a post.

Finally, I find it funny how I say that it was a coincidence regarding the 1k resonant frequency and the 1k zero line and my friend says oh no that is debatable. Pretty much just to start a debate. Now he agrees with me. Too funny.

[JayDC]

i read my db rating solely off my pioneer 500 DJ mixer, so at least your more scientific about it.. if it's 0 or over i'm happy.. to low, re cut time.. i don't cut masters tho.. I'd like too..

[opcode66]

i read my db rating solely off my pioneer 500 DJ mixer, so at least your more scientific about it.. if it's 0 or over i'm happy.. to low, re cut time..

Tickling red when gain is at midnight? Correct?

[JayDC]

2 red bars is good, 3 and i'm ecstatic, as long as i ear no distortion.. yea gain is neutral.. if i'm running low on plates and it low on volume, i dun even care, as long as i can bump up te gain.. last couple w/ my new eqing are having a hard time going past 0, and thats why i think i need more amp.. raising gain on the computer causes distortion..

[JayDC]

oh.. I cut at 112lpi, and even at 3 red i never touch grooves.. another reason i think i need new amps. vari groove would be great, an one day I'll finish my controller.. project is on hold due to budgeting issues..

[markrob]

It is my understanding (though I may be wrong) that RIAA also helps to maintain the sound of the highs in the inner diameter as they start to get degraded by inner diameter loss. Sort of like how Presto made a huge variable resistor that tracked the cutterhead as it traveled the diamter and boosted the highs as it got closer to the center.

Hi,

Not true. There is no diameter compensation present in the spec for RIAA. The need for this is type of compensation greatly diminished with the advent microgroove geometry. You still have to be careful of levels/hi freq information at the inside diameters, but its not as pronouced as was the case with larger playback stylii used before microgroove.

BTW, the total high freqency boost in the chain is much more than the RIAA alone. Because the typical moving coil head has such low mechanical resonance (1K), there is an additional ~26db of boost (at 20Khz) applied within the feedback loop to flatten the head velocity response vs. frequency. The total boost at 20 Khz from the RIAA is ~+19db above the 1Khz reference point added to the ~+26db needed to flatten the head. That's almost 45db of total boost at 20Khz! The only saving grace is that the average spectral content of normal program material falls off 3-6db per octave othwerwise we would be in a world of trouble. The older moving iron heads with higher mechanical resonances don't have to have so much boost applied and that is why they need lees power and are more rugged. It also helps that since the coil is stationary, it can be wound with a much larger gauge of wire than a moving coil head.

Mark

[JayDC]

It is my understanding (though I may be wrong) that RIAA also helps to maintain the sound of the highs in the inner diameter as they start to get degraded by inner diameter loss. Sort of like how Presto made a huge variable resistor that tracked the cutterhead as it traveled the diamter and boosted the highs as it got closer to the center.

Hi,

Not true. There is no diameter compensation present in the spec for RIAA.

Mark

please correct me if i'm wrong, I initially thought this was the reason we use a hot stylus, before that the presto eq thing was used..

[markrob]

Hi Jay,

Using a hot stylus results in lower noise (up to a point). It makes the cut groove surfaces cleaner. Its not used for diameter compensation. The need for diameter compensation is a playback issue. It reuslts from the fact that the linear velocity is lower at the inner diameters and the details cut are packed so densely that they cannot be properly traced by the pickup stylus.

Mark

[JayDC]

Hi Jay,
Its not used for diameter compensation. The need for diameter compensation is a playback issue. It reuslts from the fact that the linear velocity is lower at the inner diameters and the details cut are packed so densely that they cannot be properly traced by the pickup stylus.

Mark

is this because of the use of vari groove pitch controllers? or a stereo thing?.. when I use a hot stylus at a fix pitch cutting mono, i don't notice what you are referring to..

[markrob]

Hi Jay,

I'm not sure what you mean. Are you saying you don't see a reduction in noise when using a heated stylus or you don't encounter the high frequency playback losses at inner diameters?

If its the former, then maybe you are not heating the stylus enough or have gone too far. If you are interested PM and I'll email you a scan of the 1950 Bachman paper: "The Columbia Hot Stylus Recording Technique".

If the latter, you may not be cutting at a high enough level to reach the critical point that these effects become a problem. As I said, its less pronounced with micorgroove playback stylii.

Mark

[JayDC]

I don't encounter the high frequency playback losses at inner diameters

I cut very loud..

[dietrich10]

I don't encounter the high frequency playback losses at inner diameters
.

unless you are running an eq curve in real time while you are cutting then you are having loss of high freq playback in the inner diameters.
there is no way not to

[JayDC]

could it be possible either:

1) I just don't notice it..

2) I have to push everything above 8K so hard that it is compensating via overdrive.

3) Cutting with 500C-16 and playback via riaa reduces this effects due to more emphasis.


?

[opcode66]

Not true. There is no diameter compensation present in the spec for RIAA.

My bad. It isn't anything I've read. I know that diameter loss is not the purpose of the RIAA EQ Curve. I have read about the ways people used to combat this problem prior to microgroove and heated stylus. It usually had to do with boosting the higher frequencies toward the end of the side being cut (as in the presto add-on piece). I just assumed that the boost at the upper region helped in that respect. Not that it was defined that way because of diameter loss. But, that having the boost unintentionally helps keep the highs present at the inner diameters.

Like D said there is no way to avoid inner diameter loss. It is a physical limitation. One that I would say wouldn't appear on an Edison Cylinder because they have the same diameter from start to finish. As you get to the inner diameter there is less vinyl per second going under the stylus. So, you are trying to encapsulate audio on less and less space which means that the representation will become less and less accurate. If you record a high frequency that means there is a lot of movement of the stylus in a small amount of time. When the disc beneath you has less and less space to transfer that movement to, some of it will get lost.

I always compare it to the MP3 format. The outer diameter is like a 320kbps mp3. But, the inner diameter is like a 128kbps mp3, there is less space to fit the same amount of audio into and so naturally the sound is going to be missing something. In the case of cutting records it is the highs.