pass labs xa30 to valve amplifier.

No, you just pick the right position on the volume control and it works fine. The MP-3 has a custom-built stepped volume control composed of 96 resistors. It sounds as good as a bypass.

Hi does atma-sphere mp3 have home theater by-pass?

THe MP-3 will drive the XA30.5 with ease from an impedance perspective, I think output impedance is 250 ohm which is very, very low, especially for a tube preamp. It also uses 6sn7 tubes which always seem to be in my favorite tube line stages - oh, an really balanced.

Thank you. ill look into the ref three. I read the reviews for ref 5 and it suggests sound of a very high calibre.
Im also considering atma spher mp3. Would anyone know if this preamp would work with the pass? i have leant from here that impedence would need matching. So would only as pass pre amp work correctly? What data should i be checking? if i know this, ill research the stats for myself. Sorry for all the questions. Thank you kindly.

i have tried the Audio research Ref 5 preamp with my XA30.5. i used balanced input from my Wadia and balanced output. i found no impedance mismatch.
i suggest you try the Audio research REF 3. you might like it.

James123, a preamp that supports the balanced standard is my suggestion. The ARC is one that does not. The balanced standard (what created balanced line operation) is supposed to make the system immune to the quality/length of the cable. If the preamp does not support the standard, you will find that the cables still make a difference.

Ideally to do this the preamp will ignore the ground connection of the cable.

If I'm not mistaken, the ARC may have troubles driving the input impedance of the Pass. That has been discussed in other threads.

As a general rule of thumb, its a good idea to allocate about the same funds for the preamp as you do the amp, but individual circumstances often create wide variations :)

Thank you for reply. ive also been considering a tube preamplifier as a next step. that would also enable to keep the pass. do you or anyone else have sugesstions as to which ones would be in a similar league to the pass. cd player and pass have balanced connections so i would like to keep the balanced chord anthem, if possible. how would an old arc preamplifier fare? ive seen pre used ones that sell for around 1000 uk pounds. however, i think these are many years old. an sp8 sold recently on an auction site for 900 uk pounds. Any idea how much i should spend? i am very grateful for assistance given. thank you.

You Zingalis have the efficiency for not needing many watts (tube or ss) but if they have any severe dips in impedance and even worse, a bad phase angle in the lower ranges, a tube amp may not be the best choice. Most tube amps do not like dishing out a bunch of current at a moments notice, the Pass couldn't care less.

A tube preamp would be a step in the right direction. A tube amp may be a bigger step toward your goal.

James,
The Opera Consonance tube amps are very good(built quality and sound). The very good tube amps are quite transparent and revealing also james. There`s no 'masking' of information, they just are`nt as analytical or dry sounding as 'some' SS amps tend to be.Good tube amps will preserve the 'natural' bloom and body tone that`s less clinical in nature and more organic.You`ll certainly hear the differences in your recordings however.

Thank you. with the help of forum users here i have shortlisted : Atmasphere, ear, almarro, opera consonance ( some may view this as odd choice, but the droplet cd player i have sounds very good indeed and has proven to be reliable over past few years). The thing about the pass xa30.5 is that it is very revealing. it will make a poor recording sound very bad ( though high qulaity ones very good.) perhaps a valve amp would smooth things out when required.

Hello James,
Low power tube amps SET or PP can provide excellent impact,dynamics and clarity/transparency without a doubt. The key is selecting a well built and high quality tube amp(transformers,parts and stout power supply). Equally important is the right speaker match, one that`s efficient and has an easy drive load impedance. With the really good tube amplifiers you get realism,natural bloom and wonderful tone(acoustic instruments and vocals) that`s very difficult to achieve in many other types of amps IMO.Best of luck with your progression.

Hi James, I am in the UK and have been using a TVC control with the Atmasphere S30Mk3 with Avantgarde Duo's for about 4 years. I have had a (Chineese) tube fail - there was a loud pop but the amp and speaker were not damaged. I would now have absolutely no concern over the reliability of the Atmasphere amps. Also the tubes seem to last well - current set approx 30 months.

I have tried various SS and tube in this system and I will not return to SS. The Atmasphere is the best I have tried and I have no inclination to change after 4 years usage. In face the only reason I might change would be if a lower powered version of the Atmasphere amp was produced. With my speakers (107dB/W) I only ever see the meter showing about 1W and it is really loud!

The soundstage and bloom really draws you into the music. The main thing however is that efficient speakers like yours (and mine) seem to sound 'alive' and dynamic with the Atmasphere amp even at low levels. I think this is really important and a good indicator that a system is well matched.

Anyway, I am sure you will have fun choosing which way you want to go.

Slam and attack with clarity? Tube amps can do that in spades. A lot of that has to do with the relationship between the amp and the speaker:

http://www.atma-sphere.com/Resources/Paradigms_in_Amplifier_Design.php

Tube failure should not be a cause for speaker damage. In fact a transistor failure is far more likely to damage a speaker, which is why most transistor amps have speaker protection circuits, something not really needed in a tube amp.

Normally tube amps with the same watts seem to play louder than their SS counterparts because they handle clipping very smoothly. I don't know the percentage of the tube advantage on perceived power, but tube watts always seem more powerful, considerably so, driving a speaker - unless the speaker's impedances are so uneven as to really need SS to operate properly.

I've used XA30.5 before. It was one of the best SS amp I've used before. I've moved on to tubes, or valves, and now I own ARC VSi60. It's one of the best amp I've heard.

Hi everyone. From some of the responses here, it seems the pass xa30.5 has greater power output than 30 watts. i am still looking at valve amplifiers am aware now that a move to valve amplification may be, at best, a sideways move. Im hoping to hear a few products to judge. Am i right in thinking a 30 watt valve amplifier would not have the same volume output as the xa30.5, even though both are rated at 30 watts ( the pass very conservatativly, it seems). i am considering low powered tiode amps ( i understand they sound better) How are low powered valve amps with regard to slam and attack with clarity?
When a valve blows, can speakers be damaged? Sorry for all the questions, but i rather get some further background into valve amplification. i have picked up some very useful pointers here and thank everyone for their input.

I'm no tech-head by any means, but the published sensitivity should take into account the power eaten up by the crossover, BUT the x-over can produce those impedance dips and large phase angles that make a speaker "difficult to drive" as Magfan wrote. Applying this to the OP's question, does anyone have a link to an impedance and phase angle vs frequency curve for the Zingalis?

Thanks. Thats very interesting. The amount of sound it produces, it certainly sounds far more powerful than 30 watts.

There amps that never leave Class A? For some reason, I think my CAT JL2 worked that way, but not sure if that is even possible. Techheads?

It's a confusing amp to rate for some folks.

Pass rates it as 30wpc class A. It's pure class A for 30wpc.

Stereophile got about 40wpc class A from it in their review IIRC.

Past 40wpc, their amp moved into class A/B operation. It didn't clip until it reached about 130wpc/8 ohms IIRC. So some folks feel it should be rated as a 130wpc amp that does 30wpc class A.

So it is pure class A for its entire rated power of 30wpc.

Pass has an article on their site titled "Leaving Class A" that explains it in more detail:

https://passlabs.com/articles/leaving-class-a

We get a lot of questions about this. A typical email reads, “I can’t sleep at night – I keep worrying about where my amplifier stops being Class A. As I listen to my system, I think I can hear the Klunk as the special Class A part of the amplifier kicks in and out!”

For starters, there is no special Class A circuit that kicks in and out, and for that matter, there certainly is no Klunk. There is just a push-pull amplifier output stage which is operated at a constant idle current known as the bias. In this regard, our power amplifiers are like other amplifiers on the market. The vast majority of amplifiers are push-pull designs with a certain amount of bias current.

Push-pull amplifiers generally operate in Class A mode up to a point where the output current is twice the value of the bias current. In the Class A region, both halves of the circuit share the signal simultaneously. Beyond that the signal is handled solely by the push (+) half of the amplifier or the pull (-) half.

I think it switches at some point to B for handling peak power demand - I'm sure it is addressed in the Stereophile review, perhaps Magfan can confirm the data from Atkinson's tests.

hi. isnt the pass xa30.5 pure class a? i thought it was.

Yes, pub, per the Stereophile measurments linked above, it'll go to 130@8 and nearly 200@4.....
However, at that point you're clearly in A/B.

Ralph, I also think the XA30.5 is very conservatively rated, but one might still need the more powerful XA amps, even with "sensitive" speakers if they loaded up with drivers and x-overs. I think, but I'm not sure, that ight be the case with Pettyfeversk's speakers and why moving up the power chain with Pass has proven to be a worthy improvement for him.

Multi-way speakers with complex crossovers DO eat up power. The phase angle and impedance both need to be factored in when choosing an amp....at least on paper.
Big impedance swings with a hi phase angle at some low dip in impedance is a recipe for 'Don't Buy Tubes'.....

That's why, IMO, the 'conventional wisdom' of Maggies being a bad load is a bunch of hooie. They mainly resistive or moderate phase angle nature of most of 'em make it a reasonable load for amps which can be happy with the lowish impedance and sensitivity.

Pubul57, as best I can make out, Bobby is pretty conservative with that 89db rating on the Merlins.

Pubul57,

"I'm thinking there is something about multi-driver speakers that makes a difference in the simple sensitivity/watts equation we normally make"

I've heard/read that complex x/o's eat up power. That and the fact that you have the spectrum of music coming out of poly?/woofers, kevlar?/mids, titanium?/woofers at the same time makes me wonder how I was able to enjoy music out of "those" types in the past. The answer is, my ears didn't know any better.

These days, besides my Maggie 3.6's, I like a good 2 way with a x/o around 2.5K or higher. Trick is getting a mid/woofer to play nice up to and thru that point. I favor soft dome or ribbon tweeters also. Add to that an impedance (nice if it's 8 ohms) that doesn't vary much (say 20%) and it becomes a recipe for pleasure for me.

Pettyfeversk, your experience is with a multi-driver speaker and perhaps a 10" or more woofer? I'm thinking there is something about multi-driver speakers that makes a difference in the simple sensitivity/watts equation we normally make - seems that for some reason you do need more power and current than driving a 2-way with 7" "woofer" - even when the speakers have the same rated sensitivity. Anyone know if that is true? That just my experience, so I don't know if it is technically valid. My Merlins which are 89db played as loud as I could possibly stand and sounded wonder at lower volume with the 30 watts provided by the XA30.5. Also had the Music Reference RM9 SE (162 watts) for comparison - the Pass did not seem underpowered.

The discussion about how loud it plays is one issue but the larger question is how it plays in the low to normal volume levels. That is where we live with the sound for the most part and different matches between amps and loudspeakers produce different results.

I have difficulty with 92db / 8ohm speakers running out of juice with the 30.5 which runs to 130 watts at redline, per Stereophile measured data.

If power is the only issue, and I'd really keep an eye on the bias meter, perhaps going upline to the 60.5 would do the trick.


http://www.stereophile.com/content/pass-labs-xa305-power-amplifier-measurements

my zingalis go really loud. they are 92 db and 8 ohm. i really cant imagine anyone playing louder, unless they have a very large room. i play all kinds of music from soft female vocals, electronic,jazz instrumental,pop, quality hard rock ( queens early hard rock years still one of my favourites, not to say their later stuff was not good, just different) to european dance and alot inbetween. surprisingly , the zingalis replay dance music incredibly well with the pass.

may i take the liberty of drifting. my speakers are also 4 ohm and 91dB sensitivity.Audio Physic Scorpio ii. the XA30.5 is excellent but sometimes i feel PERHAPS i need more power. i would rather consider changing the speaker. so what is a great speaker for this amp. a speaker that can play all genres.

Thank you for the advice. I appreciate your honest views. Thats been in the back of my mind too- going downwards or sideways. something i want to avoid, of course. in fact a dealer who i contacted regarding an almarro 318b, hinted the same, so am considering options carefully. it would be great if one dealer carried a range of likely candidtates, but this is not the case so comparisons are difficult to make. i was considering a valve/tube preamp too to add to me pass. if anyone has suggestions and views, id really like to know.

and thank you to everyone with their contributions. it has given me a good start in a subject i did not know much about.

This is an excellent thread and the tubed vs solid state discussion in some ways has been replaced with the amp/preamp characteristics that you most value. As many posters mentioned, you can get different sounds depending on the tubed/solid state components you choose. The speaker you have plays a big part in determining what the best match might be. Poster Koestner talked about having 4 ohm, 92 sensitivity speakers and thinking about a solid state amp. When you have a lot of drivers and are 4ohm, I have found that you need a good amount of juice to get the speakers to really light up. There are powerful ss and tube amps. I have had three of the amps in the Pass XA series and have written about my experiences with them. The XA30.5 just did not have enough juice to push my speakers and though a wonderful amp, in my situation, I needed more power. Keep in mind that with any decent speaker, you will notice changes when you play with the amp choice, the preamp choice(or lack of), as well as the source that you use. The will all effect the sound.

XA30.5 is excellent. As mentioned above the Atmasphere might not be what you are looking for. They are not bloomy. Also, in my case a fine tube preamp will do the trick. Pass can sound more valvy than most tube amps. To get more bloom you might sacrifice detail. Be careful as you might be going sideways at best.

Your speaker seems well suited for what SS can provide - current and damping- good thing air-condition is readily available in Florida - though, I would say the M60s threw off more heat than the XA30.5. There must be a Agoner XA30.5 owner somewhere in Florida.

Well, I wish you lived near Florida. I own the Cary SLI-80 F1 and have been kicking around the idea to try an XA30.5

I guess the grass is always greener on the other side. Anyway good luck, I hear OTL tubes sound great, but my speakers are 4 Ohm 92 DB and 7 drivers (Montana XP) and was thinking that a good solid state amp could control them better.

Well, either way, you will own some very fine equipment, with what you have, or what you are considering; everything mentioned on this thread could be the basis of an excellent system, so I don't think you going to wrong with the options you are considering, once you get the preamp or no preamp issue resolved.

thank you for the response. im pretty sure my zingalis will be able to be driven by the s30. i will double check with the dealer. with 30 watts from the pass it can go really loud.

yes, lots of people have moved over to them in the uk too , it seems. i dont know anyone personally though, so its really good to get advise and pointers here. dealers , of course, only carry a very limited number of products so of course they would not recommend other products they do not deal in.

thanks

Like I said, if an OTL can drive your speaker, it is going to beat and tube amp with transformer IME. The M60s replace the CAT JL2s which they are many folks that consider it one of the very best high powered tube amps available; and I do think the CAT will drive speakers that would leave the OTL panting for breath, the transformers do serve a purpose afteal. But with my speakers that have a smooth and highish input impedance, the M60s drove me to the sell the CAT - something I never, ever, thought I would do.

Alfa, because he might very prefer it, even he loves the XA30.5s, which there is every reason in the world to love, but there is a reason so many audio loonies love tubes - try 'em, you just may like them - maintenance and all.

hi, thank for the information. how would you decribe the sound? im going to arrange a demo loan of s30, but would be interested to know your view on the sound. the vac is something i was considering too,( based on advise here from people good enough to spare some time- never heard the name before) but the dealers very far and it would be a purchase without listening unless he agrees to send a demo amp on deposit. of the two, which would you prefer?

thank you

Thanks for the reply. The picture on the site for the s30 shows connections at front. i will clear this with the uk dealer. id want the latest version. i have a chord anthem 2 xlr 1.5 metre that will just make it, i think. i guess if if they are in front you run cables under the amp? if its too short, ill have some work adjusting heavy duty wood shelves in a chimney alcove..

yes, cables at the back would have looked tidier. if the amp is not too deep, it shouldnt be an issue for me.

You cannot go wrong w an Atma-sphere or a VAC (based on what I have heard at my home). The EAR and Almarra gear is very highly regarded but I have never heard it. I'm a big fan of a very good pre-amp but one step at a time. If you are concerned about running the droplet straight into the Atma, drop an email to member Atmasphere, the designer and owner of the company. He can be depended upon for very good, impartial advice. Also member Trelja is v. familiar with the Consonance line and also will give you good advice. IMO, the Atma amps are not very tube-like in terms of the lush, romantic midrange people think of when they deride tube amps as colored. They are outstanding and the only amp I ever had that I regret selling (will get a pair of M-60s back here someday; so many amps, so little time!)

hi, thanks for the information.

i do like the pass xa30.5 very much. i have used it for nearly five years. one of the first imported to the uk, so i was told. the pass still gives me great pleasure and it has performed flawlessly.

ive never heard a valve/tube amp. i read alot on the net about the sound being different- more spacial, 3d etc. so having had my pass for nearly 5 yrs, i thought i give them a go and see for myselff. if i never hear, i will never know. for me its all about the music. its never been a case of owning this or that for the badge. sometimes i feel dealers are a bit stuck up because they have lavish premises in upmarket locations and expensive kit. they seem to forget , its only about music
.
the pass is a fantastic piece of kit that will be probably demoted to ps3 duties for my son. mad overkill for sure, but id never sell that amp as its given me so much musical enjoyment.

if it turns out valves arnt my thing, i can always get it back.

i have the XA 30.5 fed directly by Wadia cdp. i have tried various preamps including ARC ref 5 and prefer no preamp. this is my personal preference.
try tubes like Leben. but if you like the XA 30.5 why bother with tubes?

The new models have the connection in the back of the amp. I think they were in the front to provide the shortest path to the input tubes, and to keep the wire from having to run through all th electronics, etc - an approach also taking be Convergent Audio Technologies - a bit of an inconvenience, but I suspect the best sound is had that way. Seems like the market prefers the connections on the back on aesthetic grounds and shorter ICs. Of course, if you run balanced, the cheap Mogami XLR IC is going to sound about as good as anything else you buy regardless of cost. What Ralph K of Atma-sphere said regarding the Mogami, and I have no reason not to believe it.

Pupul, thank you for the reply. i appreciate the response. the atmosphere s30 is appox 1500 less than the pass xa30.5. that got me thinking. the mono bloc power amps in their range get pricier and i dont really need that much power.
its such a shame they put the connections to the front! it spoils a little what would have been a really good looking retro styled piece of kit.

do you, or anyone else have experience with cd direct as opposed to using pre? the droplet player i have is connected direct. i did try with a pre from one of my first serious hi fi purchses, a musical fidelity a3 cr, but it didnt do anything to the sound. the xlr from cd to pass sounded better.

thank you kindly

I feel pretty strongly that if an OTL can match well with you speaker in terms of power and impedance drive, it is very, very difficult to beat an OTL. Note the M60s are better yet with most speakers, especially in providing incredible bass response that seem untube like. I had the XA30.5 and the Atma M60s in my home for several months going back and forth - I don't have the Pass anymore - which does not mean it is not a great amp, it absolutely is. I would use SS if I needed to, my speakers don't need what SS can do, otherwise I might have kept the Pass with no regrets, as there no absolutes here, but if you want to possibly find "magic", OTL is likely (not guaranteed)to make you feel like you found it IMHO. Think about it: Class A, (real)Triode operation, and no transformers!

hi, ive been investigating some of the products mentioned by posters here, and others. ive listed ear, atmasphere, vac, almarra, melody. i have the pass xa30.5. i want to make a purchase that is worthwile and not a step down which would be very disappointing. a dealer here has suggested atmasphere s30, though it retails considerably less than the pass. can this be an upgrade? not too keen on the connections at front though, but ultimately i could live with that as its sound quality im after. he also is of the opinion a pre is better than direct connection. anyone mind giving me some further pointers? would a older valve amp be in the league of modern designs? i would also consider preowned one. my zingalis are 92? efficient and zingali say the minimum is 10 watts. 30 in my pass goes really loud, so would this be a true third drop in power? im after really clean bass. any further pointers would be very much appreciated. Thank you all.

Thanks you all for the information. Im looking into them all. Anyone got any other they would endorse, id like to know. Thanks.