[NoahH]

???

Googling that  i get everything from a bluetooth thingy to tweaked MBLs.

dave

GR Research NX-tremes. That is sometimes shortened here on the GR circle.

[NoahH]

You won't get high dampening with a Pass amp.  Most are rated at about 150.  If you want a high dampening factor consider a Parasound JC5 at 1000.

Yeah - I should have been more precise. I was referring to First Watt; I would love to do one of those (sit-3 in particular looks like my cup of tea) but they they have tube amp levels of damping - like 40. I should have said 'not low' damping.

That said, I had not thought about parasound. I had no idea that the JC5 was that high. I have mostly seen that with class Ds. I may need to look at JC5s more, or I assume a pair of JC1s would be the same. I think I just have a bias because I constantly see sentences of "I upgraded from my A21 to xxx and it was a huge improvement", but I guess that is pretty far down-line from the JC5.

Thanks!

[NoahH]

Once you hook the speaker cable anything over 40 is pretty much the same.

dave

These are open baffle speakers. There is no damping from a box.

[planet10]

GR Research NX-tremes.

Impedance varies by a bit over 2:1, if the R_out is too high you might start hearing the peak at the XO between mid and top. Right where the ear is most sensitive.

The bass peak resonance is fairly large too, but how that works out is sometimes strange.

dave

[planet10]

(sit-3 in particular looks like my cup of tea) but they they have tube amp levels of damping - like 40

SIT-3 is a very nice amplifier. I will probably have to sell mine. Too many amps, and i have another amp by Nelson waiting to be built (VFET).

40 is a fairly high ds,pimg factor for a PP tube amp (i have seen one with a 2 damping), and typical SE tube amps will have R_out of about 1 to 4, damping of 8 to 2

SIT-3 has an R_out of 0.26, 8/0.26 = 31

dave

[planet10]

These are open baffle speakers. There is no damping from a box.

No mention of damping from the box was made.

dave

[planet10]

You won't get high dampening with a Pass amp.  Most are rated at about 150.  If you want a high dampening factor consider a Parasound JC5 at 1000.

https://p10hifi.net/forum/RichardPierce-DAMPING-FACTOR.pdf

dave

[NoahH]

Removed response for a minute while I check something.

[newzooreview]

You won't get high dampening with a Pass amp.  Most are rated at about 150.

The XA-25 has a damping factor of 500. (source: my XA-25 user manual). It drives the two 15" woofers on my M3 Sapphires extremely well, with deep, textured bass.

The XA-30.8 is 150 as are a number of other Pass designs (both First Watt and Pass Labs).

Steve Guttenberg has done a number of Nelson Pass interviews which are insightful: https://www.youtube.com/c/SteveGuttenbergAudiophiliac/search?query=nelson

[I.Greyhound Fan]

Yeah - I should have been more precise. I was referring to First Watt; I would love to do one of those (sit-3 in particular looks like my cup of tea) but they they have tube amp levels of damping - like 40. I should have said 'not low' damping.

That said, I had not thought about parasound. I had no idea that the JC5 was that high. I have mostly seen that with class Ds. I may need to look at JC5s more, or I assume a pair of JC1s would be the same. I think I just have a bias because I constantly see sentences of "I upgraded from my A21 to xxx and it was a huge improvement", but I guess that is pretty far down-line from the JC5.

Thanks!

I owned the A21 and it was a good amp but no where near as good as the JC line.  The JC1's were a Stereophile Class A+ for over 10 years and are still considered a reference amp.

[mkrawcz]

I owned the A21 and it was a good amp but no where near as good as the JC line.  The JC1's were a Stereophile Class A+ for over 10 years and are still considered a reference amp.

I owned a pair of original JC1 monos for 5 years. BHKs destroy them. Maybe if they where half the price they would be ok, but to me they are way overrated at their price point. I haven’t had a chance to listen to the new version though.

[I.Greyhound Fan]

I owned a pair of original JC1 monos for 5 years. BHKs destroy them. Maybe if they where half the price they would be ok, but to me they are way overrated at their price point. I haven’t had a chance to listen to the new version though.

I don't doubt your opinion of them but JC1's rarely come up on the used market and the BHK's are for sale on Audiogon all the time.
It's all about system matching and personal preference.

[RDavidson]

Choosing the right amplifier based on damping factor is very very tricky. Obviously you have to consider the speaker's load on the amp, as well as consider the size / moving mass of the drivers as well as your room size and listening preferences. It's a difficult balance that really requires experimentation with different amps. Where a First Watt amp may be perfect for one person and their system/room/listening preferences (with the same speakers as you), this First Watt amp may not work for you and your setup. Something interesting about the XA25 is while it has a high-ish listed damping factor, it retains a wonderfully fleshed-out sound. Not too tight and not too loose in the bass. You'd think it'd be a horrible match for speakers like Omegas, which are easy to over-damp, but that's not what I hear. I love the XA25. I've had mine for a few years now and still think it is the best all-round amp I've owned. I have also owned the XA30.8 as well as many other Pass and First Watt amps. The XA30.8 had the "biggest" bass of any amp I'd ever owned regardless of damping factor. It was also quite the space heater and HEAVY. Hope this helps.

[Freo-1]

When it comes to accurate control of the speakers,  I was taught the higher the damping factor,  the better the speakers would perform.  The Devialet Expert Pro has a damping factor of 8000,  and provides some of the clearest, deepest, and tightest reproduction of music I've come across in this hobby.  I think high damping factor for a power amp is a good thing overall. 

[planet10]

... the higher the damping factor,  the better the speakers would perform...

A myth. Propagated by those with high damping factor amplfiers.

The right R_out (damping factor is a bit of a bastardized inverse), is the one that works best with the loudspeaker being used. That loudspeaker could have a wild impedance which means you want a low R_out amplifier, if the loudspeaker is well damped, and has a “flat” impedance curve one can take advantage of amplifiers that look more like a current amp, or even a current amp ( R_out > speaker impedance.

Listening to different loudspeakers using a variable transcondictance ampifier (a dial on it that changes the  R_out from near infinity to near zero). Every loudspeaker sounded best with a different setting.

dave

[I.Greyhound Fan]

I don't think that you should buy an amp based on dampening factor.  My A21 amp has a dampening factor of greater than 1000 and my Pass X250 has one rated at 150.  I much prefer the bass of the Pass.  Is it slower? Yes, but it sound more musical and natural and has greater impact.  There is more to an amps bass than dampening factor.

[Freo-1]

Whilst I'm onboard about not  basing an amp purchase solely on damping factor,  it is a factor regarding the ability of the amp to control the speaker.  It's one of the factors to consider when making a purchase. 


I've owned MANY different Papa Paas amps over the years,  and have a great respect for Mr Pass and his products.  Prior to jumping on board the Devialet train,  Pass gear was always my go to option.  Have to say that the Devialet Expert Pro amps do an amazing job of controlling the bass, especially compared to more traditional amp designs.  Speaker Active Matching takes bass to another level.  To me, it sounds much more accurate,  especially stand up acoustic bass playback.   


So, I don't agree better damping is a myth at all.   Having said that, what a given listener prefers is a whole different story.

[Jaytor]

I've used the following amps with my NX-Oticas - Parasound JC5, Pass F5 Turbo monoblocks (50W/ch), Neurochrome 286 monoblocks with 400VA  100,000uF LPS), Purifi Class D monoblocks with huge LPS (1500VA, 134,000uF for each monoblock), Pass XA60.8 monoblocks, and 300B P-Set monoblocks.

Of these, I was least happy with the F5 Turbo, that this was my first DIY amp build in many decades and I don't think my build did the design justice.

The Pass XA60.8 is probably the best match, doing everything quite well with excellent dynamics and plenty of power reserves.

I like the sound of the 300B amps, but they are a bit underpowered which is noticeable with highly dynamic music. On music that is primarily vocals with a couple of background instruments (jazz, folk, etc.), they are sublime.

The JC5 and my Purifi amps are quite similar in the way they sound. Both have excellent dynamics and clarity and a nice sound stage (but doesn't match the XA60.8 or 300Bs). The JC5 is a bit smoother sounding on lesser recordings and has a bit more energy in the mid-bass. But the differences between it and the Purifi amps are small.

The Neurochrome amps sound nice, but are a bit on the boring side. They really don't do anything bad, but nothing spectacular either. But for their cost, they do pretty well. This was the cheapest amp (pair) to build and sounds better than my F5 Turbos (but again, I think this is more an issue with my build than with the design).

I think the best overall sound for the money goes to the JC5.

Keep in mind that I am using the NX-Oticas with stereo triple-driver servo OB subs which handle the bottom couple octaves, so it's a bit difficult to assess how much these amps are contributing to bass performance.

[opnly bafld]

A myth. Propagated by those with high damping factor amplifiers.

dave

Another good read, but I don't get my hopes up that it will change minds.
https://butleraudio.com/damping1.php

[Freo-1]

A damping measurement of 8000 can only improve the control of the speaker cones.  The proof is in the listening,  along with measurements from the speaker.