Phono Stage upgrade to complement Dohmann Helix One Mk 2

Mijostyn, Speaking for myself only, I am curious to learn what you use to effect steep crossover points in the digital domain. 

I didn't state it previously, but the crossover is a matter of trade-offs.  Mijo makes the case for a very steep hi-pass filter.  The rationale for that is you want as much as possible to reduce the burden on the main speakers to produce bass frequencies.  To do that, of course a steep HPF slope is in order.  The problem is that filters with very steep slopes are very likely to color the upper frequencies (because a lot of parts are needed to effect a steep slope, each of which is likely to reduce fidelity) and to introduce phase shift.  (I am not convinced phase shift is such an audible problem if kept moderate, especially with our dipolar radiators.)  One reason I am intrigued by the Pass XVR1 is that it can do a 24db/octave slope with Linkwitz-Riley character.  In L-R, the phase shift is no worse than that of a Butterworth 6db/octave filter. The XVR1 is a stand alone electronic crossover; in theory you would use it with a subwoofer that had no built-in crossover and which was driven by a separate outboard amplifier.  Does anyone know of a commercial subwoofer with built in x-over and amplification that also affords a L-R filter?  On the other hand, selecting a HPF with 6db/octave slope, whether done actively (using whatever HPS is built in to your chosen high end subwoofer) or passively, using a capacitor in series with the amplifier input is least likely to do harm to the main speaker's output.  Obviously, in a given case with lots of $$$ having been spent, a steep HPF might sound great.  That's why I am curious to know what Mijo uses for a digital filter ahead of his speakers.

drbond, for your amplifiers with a 22K ohm input impedance, about an 0.1uF capacitor would give you a HPF at 80Hz, 6db/octave, assuming a single-ended input.  My choice among capacitors I have heard would probably be a Russian SSG silver mica capacitor,

Hi drbond:

I’m using the KRONOS PHONO PREAMPLIER.

I only can say that it deserves a chance.

I could use words to describe the sound and silence, but 

much better if you can test it. No come back.

Can support all LOMC.

I enjoy the electrostatic sound of SOUNDLAB U-545

and Atma-Sphere. The combo is magic when you feel all details.

Regards,

My speakers are Soundlab 545

I would suggest that going a bit slow is not a crime.,, and doing it right can be a chin-scratcher.

You can call or find dealer and look at what is on offer.
And some manufacturers answer the phone.

I could not find Velodyne, but Martin Logan has a bunch of dealers around Sarasota, and Vandersteen in Miami or Atlanta.

My pre-amplifier has two outputs: RCA and XLR, so I can run the RCA to the amplifier and the XLR to the subwoofer, or vice-versa, as the amplifier has both RCA and XLR inputs.

That works if the sub needs an RCA input and has its own filtering scheme.
I have not been overly shy in liking the approach of pulling the signal off of the binding posts.

I was leaning towards a lower crossover for the HPF, something like 80 Hz, or maybe 60-80 Hz, to keep the midrange in the ESL’s

Again I have not been shy in advocating the 1st order (6 dB/octave) at 100Hz.

• You attach the HPF at the amp side of the cable.
• Attach the line level cables to the speaker posts.
• Turn some pots on the back to set the levels.

and then you’re I’m done.

I would suggest seeing what the fuss is about, and if you go with a Velodyne or ML, then you at least went in with the eyes open.
 

Holmz, the first two of your last 3 bullet points would result in bypassing the main amplifier.

Hmmm. . .I’m back to the consideration stage: apparently, the most neutral approach to add a HPF in my current system is via a high-grade capacitor. However, these capacitors only give a 6 db / octave adjustment, which means starting at 80 Hz (so that the mid-range isn’t affected), would only drop the volume by 6 db at 40 Hz, which is the lowest sound played by the cello, although the piano may drop to 30 Hz on occasion, which would give about a 9 db decrease in signal to the main ESL speakers.

To put things in perspective, one click on the volume knob on my pre-amplifier is about 2 db (and it is usually set around 26 clicks) so we’re talking dropping the volume only 3 clicks for most low frequencies, and at most 4 clicks for the lowest, which is only going to be about a 10-20% drop in volume for these frequencies.  So I’m not sure a standard analog capacitor HPF is going to make much of a difference in attenuating the signal to the main ESL’s; and apparently, the built in HPF in subwoofers are also the standard 6db / octave. Ideally, I would get a high quality analog HPF, which would minimally affect the SQ, and filter at 24 db / octave. . .but that may be like the tooth fairy: impossible!