PLEASE match Advice Pass Labs X350.5 (20k) to Hovland HP-100 (2500ohms) Miss-match ???


GUYS / GALS NEED YOUR HELP PLEASE!

A friend said this preamp is outstanding and will sound great with Pass Labs amps and to not get caught up in the specs but the measurements say different.

Pass Labs X350.5 amplifier with input Impedance 30k ohms Balanced or 20k ohms Single ended* 
(*source Pass Labs Manual)  

Hovland HP-100 source impedance 2500ohms* 
(*source Stereophile) 

Guys / Gals, can I used my Pass Labs X350.5 amp with Hovland HP-100 preamp? Has anyone used Pass amps with Hovland pre's. I will be using Magico S5 Speakers and Bricasti M1SE DAC but want it to sound the best it can. Should I just stick with the Aesthetix Calypso pre I was leaning toward before my gut said to go for the Hovland HP-100

Hovland HP-100 Preamplifier: * Output impedance: approximately 2500 ohms or according to Atkinson, Hovland HP-100 (2500ohms) its source impedance was high at 2.4k ohms, rising to 4.3k ohms at 20Hz. The partnering power amplifier would best have an input impedance of at least 47k ohms if the bass is not to sound lean*. The Pass Labs doesn't meet the x10 requirement it is supposed to but it is sort of close when looking at it. What do you guys think? I am not sure what to do but you guys will know what to do?

Stereophile: Its input impedance was a usefully high 100k ohms in the midrange and bass, with just a small reduction to a still-high 86k ohms at 20kHz. Despite the claim that the HP-100 uses a cathode follower output stage, its source impedance was high at 2.4k ohms, rising to 4.3k ohms at 20Hz. The partnering power amplifier would best have an input impedance of at least 47k ohms if the bass is not to sound lean.

Read more at https://www.stereophile.com/content/hovland-hp-100-preamplifier-measurements#YZXZfGLbbL2COkLR.99 https://www.stereophile.com/content/hovland-hp-100-preamplifier-measurements#YZXZfGLbbL2COkLR.99
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John, I’ve noticed that apparent anomaly in the specs of the Pass .5 amps in the past, and I’m pretty certain it is a mistake in the specs, and what was intended was 20K single-ended/30K balanced.

Al, thanks for your input. I might have to contact Pass directly to get the true numbers.
I just assumed that the 30K SE/ 20K BAL was correct because of Threshold history.
Many old Threshold amps had a SE input impedance of 50Kohm while the Balanced inputs were rated at 600 ohms input impedance.

https://www.stereophile.com/content/threshold-stasis-sa12e-power-amplifier-specifications

Also, Coda amps, which were designed by 3 ex-Threshold engineers, always had very low balanced input impedances as well.

The spec sheet on the Model 15/15.5 shows an SE input impedance of 50K with a Balanced input impedance of 1K ohms.

http://coda.cc/product/index.php

So I just assumed it was something in this family design that always had the balanced input impedance lower than the unbalanced input impedance.

It does look like Nelson has addressed this flaw with the .8 series.

Cheers,
John


PS: I see in Stereophile's measurements of the XA60.5 amps they measured a 17K input impedance in both SE and BAL. Who knows which figure is right?

https://www.stereophile.com/content/pass-labs-xa605-monoblock-power-amplifier-measurements
If I go SS pre for max matching I have these 2 options for exact same very good price. The matching brand via same company obviously would be best matchm but have heard more than a couple times it can be kind of sterile which I hate and the Ayre. No one ever calls them sterile.


Same money
Pass Labs XP-10 
Ayre K-5xeMP

For $800 more and money matters 
CJ ET3SE 

or add another $300
ARC LS27

These tube amps have low enough source impedance to work as they use JFETs to solve the problem.

I'm leaning towards Ayre or CJ I think although part of me still wants the BAT - what do you guys think? Thx 

Oops guys just got back me. 
Ayre K-1xe for $150 more than the ARC -

i head these are great - long in the tooth but great - really want the one out of these that is the best but also match impeidamce wise and will match my Pass amp best and work with Magico S5's - so I can swing any these price wise?
The Pass XP-10 pre and Ayre K-5xeMP are only 2/3 the price of the others if that helps at all.