Ortofon stl-732 limiter
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- subkontrabob
- Posts: 284
- Joined: Fri Oct 30, 2009 5:40 am
- Location: Helsinki, Finland
I envy you for having an old croc around to receive knowledge from! I suspect we'll see lots of interesting and enlightening posts from you in the future.Serif wrote: He said he'd demonstrate for me how to tune the stylus heat by ear (listening for surface hiss to minimize and no further) as well as setting the feedback.
You have a unique opportunity, I hope you can make good use of it.
STL and Ortofon
Hi Andrew,
I modded the STL over 10 years ago so don't remember exactly what I used. Probably used 5532/34s then, would probably use LM4562s now.
If you need the schematic and hookup for the inverse RIAA to the control input PM me and I'll send it to you.
I have used Ortofon heads and yes, they are ridiculously fragile. Not really a fan... Future Disc had to have theirs rebuilt every three months! Not joking! An STL is almost a necessity to protect it. Also...if you ever see the Temperature Meters moving to LOW frequency stuff, put in a high pass filter at 30Hz immediately. It means there is low frequency information at or near the excursion limit. It will literally tear the head apart. That is the least forgiving thing about an Ortofon. I'll bet more Ortofons have been destroyed by LF than HF.
Best,
Kev
I modded the STL over 10 years ago so don't remember exactly what I used. Probably used 5532/34s then, would probably use LM4562s now.
If you need the schematic and hookup for the inverse RIAA to the control input PM me and I'll send it to you.
I have used Ortofon heads and yes, they are ridiculously fragile. Not really a fan... Future Disc had to have theirs rebuilt every three months! Not joking! An STL is almost a necessity to protect it. Also...if you ever see the Temperature Meters moving to LOW frequency stuff, put in a high pass filter at 30Hz immediately. It means there is low frequency information at or near the excursion limit. It will literally tear the head apart. That is the least forgiving thing about an Ortofon. I'll bet more Ortofons have been destroyed by LF than HF.
Best,
Kev
Kevin Gray
Forgot to mention... Didn't up the threshholds, I "upped" the frequency of all the low pass filters in the audio section. If you do this you will have to experiment with a lot of HF program material to find out what works. I think I went up to 30kHz. If you go higher it can let HF garbage from the control amp into the audio. It also changes the response time slightly because the filter has to "slide farther down".
Kevin Gray
- TotalSonic
- Posts: 227
- Joined: Tue Sep 30, 2008 7:08 pm
- Contact:
Has anyone heard the Etec DBTL20 bass and high frequency limiters? Seems like they were specifically made to deal with the issues of limits to excursions and acceleration in the Ortofon heads. They're being offered for 1800 Euro at http://www.etec.dk/ortofon-vintage.html (halfway down the page). Curious if anyone has heard these units.
Best regards,
Steve Berson
Best regards,
Steve Berson
- TotalSonic
- Posts: 227
- Joined: Tue Sep 30, 2008 7:08 pm
- Contact:
Hmm. I might like to keep the speed of response (for head protection) until I get a second head at least, even if the highs get sucked a little. It's analog, after all. I tend to think a lot of CDs sound bad because we're used to being pampered by for-vinyl mastering (and tape), but those kinds of compression aren't always employed in the interest of realism and thrilling transients. Ouch! I don't like sitting in the front row at the Symphony, nor do I sit in Bass cabs at Raves. (; I love a tickly pillow of dulcet tones and don't want to cut anything more harsh than, say, the sound of '72 Zepellin. Is that even too threatening for an Ortofon?cohearent wrote:Forgot to mention... Didn't up the threshholds, I "upped" the frequency of all the low pass filters in the audio section. If you do this you will have to experiment with a lot of HF program material to find out what works. I think I went up to 30kHz. If you go higher it can let HF garbage from the control amp into the audio. It also changes the response time slightly because the filter has to "slide farther down".
Your advice about the over-excursion failure mode of the DSS' rocker assembly is consistent with what Mike F. told me about it. But he warned mostly about 808 boom and bass samples as in young-people (l: night club techno and rave on 12" at 45, one song per side... I was hoping that LP length programs of Neo-Bluegrass, Rock, and Jazz (things with already a Symphonic spectral halo, and not synth hats, or whatever) would be able to be cut with the DSS line, relatively safely, without leaning on the High Pass filter. Also, while I have seen the Etec Bass limiter, I began to think, if I can just get used to cutting only a very soft telephone-voice for a while I might be able to use this system without blowing or bending the head (; (j/k)
Another little anecdote about this purchase was that I was this close to going for an overseas VMS 70 that became available after negotiations had begun on the LS. However, the only way to get the VMS even within 5k USD of the ultimate LS sale price was to accept the Neumann with a blown SX-74. ):
Anyway, if you know of a 3D, SC-2, or SX-68, I'm gettin' interested... If the -74 can blow in normal use, it's too expensive! (:
Also, when I wrote, "... higher valued thresholds," though I remember not liking how I'd phrased it, I honestly _did_ already grasp and mean that you changed the values of the frequencies of the threshold steps, and not the amount of attenuation, per se. This is because I did read your reply with care and because I had already seen the treble limiter over in the seller's office and was intrigued by the fact that the meters don't show decibels of reduction, they show frequency (in kHz) of the variable valued limiting action. The seller warned me about how it can be program-dependent whether it will help the cutter without hurting the highs, but, he admitted (because it was purchased right before he sold his lathe) not ever getting around either to employing the control inputs for the side-chain action you describe, or ever removing the Neumann accel limiters from the chain, so it was always double-de-Essence, if you will. He said he sometimes liked how if set to around 18 kHz on most highs he would see it just "kiss" 16 kHz on a loud high hat without ruining it. But, even though both channels are independently limited, the results are not always good... The STL-732 is a very neat machine which should be part of the Ortofon kit.
What about the older tube version?
Fwiw, I believe I am also getting the not-so in-demand but hopefully useful CPS Correction Amplifier, which has the Ortofon-dubbed ? "Compatibility Stereo Mode," which is their EE (mono-ing and attenuation of bass) as well as their HPF/LPF.
Thanks,
Andrew
tube stl 631
Hi Andrew,
I've wondered about the 631 also. I borrowed one several years ago and it was humming loudly...obviously needed some power supply work...so didn't really play with it.
It is a very simple circuit, nothing like the 732. I would like to try one again some time.
Best,
Kev
I've wondered about the 631 also. I borrowed one several years ago and it was humming loudly...obviously needed some power supply work...so didn't really play with it.
It is a very simple circuit, nothing like the 732. I would like to try one again some time.
Best,
Kev
Kevin Gray