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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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jperry
2,444 posts
 
OP,

Reading through this thread it seems that you are reading reviews, listening to advice from others, and looking at specs for components.

My suggestion is that you call Reno HiFi. They have new, used and demo product from Pass. They allow you to demo, and return if not satisfied. Get a Pass preamp and try it in your system.

I don't own any Pass (I have an Aesthetix preamp and amp), but you already have the Pass amp, so I would recommend trying a Pass preamp.

Good luck with your search.

Jim Perry
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fsmithjack OP
712 posts
 
OK - so I am committed to make the BAT work if you guys think it will. I emailed Nelson also. 

That said:

I can get a Pass Labs XP-10 for similar price but with my Magico S5 Speakers everyone says the lean sounding lower midbass can really be helped with the tubes.

Not that Magico S5 bass is lean but the sealed cabinet is an adjustment for folks like me used to warmer ported sounds.

Plus I love tubes and thinking best to keep some tubes in there I think that will be more toward my liking but I have never heard the Pass XP-10 and if it will be that much better match wise maybe I just go for that?

Wish I could try it out in my system but buying used so not possible.

Thanks Al Kali - buying used and really just looking at used pre's that are available today via the Agon, the Marts and the bay and are under $3k is how I have come up with the ones I am thinking about.

Trying to not make a mistake and give my speakers the chance to sound their best. I will try my Bricasti direct also but I have always found I love preamps. Maybe it is mental but the Bricasti is also known to be at its best when volume is wide open and a pre does the attenuation chores imo ymmr. 

I will update everyone with what Nelson thinks but would love what you guys think - also maybe there is another pre i am overlooking or something.

You guys are the best of the best. This is the best place for audio anywhere. 
yogiboy's avatar
yogiboy
5,615 posts
 
Have you given Conrad-Johnson a look?
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almarg
9,670 posts
 
... so I am committed to make the BAT work if you guys think it will.
It will certainly work in a fairly reasonable manner, but as I said it would be introducing a known compromise, that IMO represents a significant risk that you would ultimately be disappointed.

I’ll add that in addition to the relatively small but likely perceivable amount of roll-off of the deep bass that would result, undesirable phase shifts could very possibly occur to an audibly significant degree in the bottom octave or two, that would vary as a function of frequency.

In any event, good luck however you decide to proceed. And thanks for the nice words. Regards,
-- Al

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jond
5,740 posts
 
So if you are just looking at used preamps here this caught my eye.

https://www.audiogon.com/listings/tube-just-factory-serviced-perfect-2017-09-25-preamplifiers

No affiliations and a max output impedance of 1200 ohms would seem to work on paper, I'm not much of a measurements guy. It's also well constructed with a very stiff outboard power supply. I've never heard any Canary stuff personally but its always looked intriguing to me and this fits your price range.
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