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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
fsmithjack
fsmithjack's avatar
fsmithjack OP
605 posts
 
Thanks - this might be a dumb question but until funds get back up a little can I used rca single ended from M1 Dac into the Ayre then use balanced out to the amp? I know best but would it be ok for short term? Thanks  
almarg's avatar
almarg
8,673 posts
 
Fsmithjack, re your question just above, that would be no problem.

BTW, I see that the K-1xe has a relatively low specified input impedance of 10K per phase, which means a balanced input impedance of 20K. And I suspect that it probably also means that the unbalanced input impedance is 10K, although that is not stated explicitly.

Your Bricasti DAC will have no trouble with either input impedance, but if you envision the possibility of ever adding a tube-based source component to your system chances are good it would have the same kind of impedance compatibility issue with the preamp that we’ve been discussing about the preamp-to-amp interface.

Regards,
-- Al

dlcockrum's avatar
dlcockrum
2,105 posts
 
fsmithjack,

I can only offer that I have used the K-1xe’s SE inputs from a tuner (and probably other things I have forgotten) and also the SE-only tape monitor input/output with no issues and found the sound quality to be excellent.

I do recommend that you take advantage of the benefits of the Ayre’s true-differentially balanced XLR inputs from your most excellent DAC as soon as you can swing it financially, but you clearly already get that.

Dave
lewinskih01
793 posts
 
@fsmithjack 

Sorry for this post out of place, but digging the forum I saw you have experience with both Yamamoto and Triode Lab SETs, which are strong condidates to be my next amp. Would very much appreciate your input as to differences in sound and build quality/aesthetics. I tried emailing you but Audiogon doesn't offer the option, hence this post.
Sorry again and thanks in advance!

fsmithjack's avatar
fsmithjack OP
605 posts
 
No problem - this one easy - the Triode Lab 2A3S-FFX wiped the floor of the Yamamato in every single way. More linear, dynamic, incredibly smooth and one of the best audio amps I have ever heard. The Yammy is a great amp and does so many things well but the Triode Lab is in another league.

Frank at Triode labs is amazing and one of the best people I’ve ever dealt with anywhere with any brand. Super friendly and will support you to end of earth and then on the other side as well. Love that guy!

To better the Triode Lab you will need to get into the AudioNote, Kondo, Shindo gear at 5x10x20 times the price, These companies gear at similar price point isn’t even close. You need spend way more. No body is making anything, anywhere in Frank’s prices that comes close. His trannies, chokes, caps, wires, resistors are all the best and everything is hand made by him. Could go on and on about this creamy gear. I have shifted gears and decided to try the other end of the spectrum but I am sure I will own his gear again. I liked it too much!
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