Review: Mcalister Audio PP150S Tube amp

Category: Amplifiers

I like to listen to Jazz & female vocalists and here is a list of the CD's I base this review on.

Dianna Krall- The Girl in the other room
Cassandra Wilson - Belly of the sun
Van Morrison - What's wrong with this picture
Van Morrison with Georgie Fame and friends
Eva Cassidy - Songbird
Terence Blanchard - Let's get lost
Fourplay - Journey
John Previti Quartet - Swinging Lullabyes
Kendra Shank - Afterglow
Steve Bell - The feast of seasons
The Fred Hersh Trio - plays Coltrane,Davis.Ellington ...
Christy Baron - Steppin'
Patrica Barber - Cafe' Blue
Steve Bell - Simple songs
Dick Hyman - plays Duke Ellington
Tuck & Patti - various
Rickie Lee Jones - various
Alison Krauss - Lonely runs both ways
Alison Krauss - Live and other various CD's

For all the technical information and more about the builder (Pete) please go to the website below.

This amp is hand built one at a time by Pete of Mcalister Audio with all point to point wiring. His design is fresh and new. His web page gives all of the details for you tech geeks. Bottom line is this design is not like most tube amps. The amp uses horozontal sweep TV tubes for output tubes.

It has a very DIY look so for those of you who desire top notch fit and finish on the exteior, this amp may not be for you. On the other hand, for those of you you don't mind that hand built DIY look, your in for a real treat.

Special note here. My amp has the bias pots and bias meter probe inputs located on the top of the amp next to the output tubes. I think the stock model forces you to remove the botton plate while the amp in on its side. That is not a good or safe way to bias in my book. Go for the upgrade. This may be stock now, but I am not sure. I also understand Pete is now making this amp with a more traditional glossy finish. I have seen a picture of the new amp and it looks very good indeed.

I have owned many fine tube and SS amps over the past 7 years. Let me start off this review by saying this amp takes a back seat to none of them in the way it delivers beautiful music. Remember, this amp sells for $995 new direct from Mcalister Audio. Shipping and the upgrades mentioned above will add some $250. With this in mind, I can confidently state this amp is the best value in high end amps on the planet. At least from what I have heard :-) Yes, I like the amp very much.

The amp reminds me of the Wright Sound 2a3 SET monoblocks I owned about a year ago. They have that same inner detail sparkle to the highs. This amp really has an immediate and intimate sound personality. The instruments are presented to you in a clean, raw manner - like live music. No glossing over the detail or "fuzzing" up the works here.
With each CD I played I became more and more aware of each instrument and the emotion of the words sung. This amp somehow releases more of the music's energy. I forgot to mention I also owned the Berning ZH270 amp and this amp has that same speed and PRAT. This is a fast sounding tube amp folks.

The bass is deep and not thick sounding like some tube amps I have heard. Played at loud volumes the bass is not quite as controlled as some of the SS monsters I have owned like the JC 1's and Mac 402. The bass has good definition and rolls along fast with a minimum of overhang. Again, at high volume levels it was bested by good SS amps.

This amp really sounds like a more powerful 2a3 SET amp. Amazing "see through glass" presentation of the highs with smooth and full mids. Botton end is more robust then a 2A3 SET amp to be sure. Stock power cord sounds as good in my system as my other more costly upgraded cords.

The stage size is not overblown, but realistic with more of an imtimate feel and experience. Imaging is first class and a joy to experience.Individual instuments are easily picked out and followed. Here are some single words that come to mind when listing to music with this amp.

- quiet (paired with my Pre6 - no noise out of my speakers - none - dead quiet)

- sparkle
- energy
- emotion
- clean
- clear
- smooth
- quiet - let me say that again

The amp comes with a nice separate power supply. Mine makes a little mechanical buzzing noise that can be heard a couple of feet away from it. I dont hear it from my listening position. My experience is some transformers are more quiet than others and what you experience with a particular unit is based on your home electricity and luck. I have found this with all transformers in gear.

Summary. Is it the very best amp I have owned. Well, no I can't say that. I am learning no amp can be defined as the best. Once an amp breaks into the realm of world class sound the differences become ones of tradeoffs. It is close however. Overall it gives me as much joy as any amp I have owned. It will outperform most tube amps costing many, many times more. I know of no amp that sounds this good for $1000 - $1200. For many it will be a total revelation or first real look into your music library. It can stand toe to toe with the mega $$ amps. While some will do "this or that" better, this $1000 amp will in turn do "this or that" other thing better. If you desire that intimate music setting with wonderful inner detail exposed before your ears, then this amp is world class.


Associated gear
Dali Grand Speakers

Bel canto Pre6 preamp

Muse Thalia CD/DVD player (most recent updates from Muse

Accoutic Zen Hologram II speaker cables

Component Plus Transparancy IC's

Blue Marble Audio power cords

BPT 2 Line conditioner

Powervar ABC1200 line conditioner

2 direct 15 amp lines to listening room

Echo Buster sound treatment throughout the room

Mapleshade heavy brass footers under all gear and speakers

Similar products
Amps I have owned

Thor TPA 30 monoblocks
CJ MV 60
Wright Sound 2A3 monoblocks
Bruce Moore Dual 70
Various hyrid Blue Circle amp
Parasound JC1 monoblocks
Mcintosh MC402
Belles 350A monoblocks
Monarchy SE160 monoblocks
Marsh a400s
Joule VAMP
Wavac SET amp (dont recall the model number)
For some reason some of the spec data did not post on my review. The amp is rated at 75 watts per channel. The small front tubes are said to last for 10,000 hours while the output tubes will last for 5000 hours. Circuit is designed in a way to give long, long tube life.
Boy, what an excellent review! You really did a great job of expressing the sound character of this amp. In this day and age of overpriced, highly marketed competing brands, it's refreshing to find another "hidden gem" out in the audio market place.

BTW Grannyring - how did you happen to stumble on to this amp?

Again, thanks for taking the time to pen your impressions for all of us!
It came up used here on Agon - first one I have even seen. I started reading the website and decided to give it a try as I wanted a tube amp without having to spend big $$.

It was between this amp and several of the "cheap" Chinese amps found here and on Ebay. Had a gut feeling this handmade amp from one man in Canada designed with a new and fresher circuit approach would be best.

Boy did this amp knock me over. Transparancy is unsurpased to my ears and experience. Amp is a steal and serious high end piece.

You are not the only person who saw and considered the listing for this amp. If the timing of this listing (with my PreAmp off for repairs, and spending more money than planned on house remodeling) had not been so unfortunate, I am not sure that you would have had the pleasure of landing it. :o)

With all of that said, good for you. Your review is terrific. Thank You! Some thoughts and some questions if I may...

You said: "Stock power cord sounds as good in my system as my other more costly upgraded cords". In reading the designers language on his website, it would seem that he is particlarly pleased with his power supply design, stating that "This transformer design produces its output voltage in relation to the 60 Hz line frequency producing a stable secondary voltage that does not vary with current demands of the amplifier or input voltage variances from 90 to 135 volts". What aftermarket PCs did you use? Did you notice any changes at all with other PCs?

You said "The stage size is not overblown, but realistic with more of an imtimate feel and experience". Did you find that this amp was constrained by the physical position of your speakers, or did it tend to "fill the room with the acoustic space"?

You said "The amp comes with a nice separate power supply. Mine makes a little mechanical buzzing noise that can be heard a couple of feet away from it. I dont hear it from my listening position". I fear that I might find this a bit troubling. Have you spoken with the designer regarding this. Did you have any desire to try to mitigate this?

You said "If you desire that intimate music setting with wonderful inner detail exposed before your ears, then this amp is world class". Being one who finds himself commited to electrostatic speakers, this statement of your really caught my attention.

Thanks again, for a highly informative review. I am especially appreciative as I had so seriously thought of this unit. I appreciate your efforts in writing this.

Gary, good questions. First, the power supply was damaged in transit and a $20 DIY fix rendered it very quiet. Check my threads and read about the fix. The title of the thread is "My tube amp power supply is buzzing away Help"

Regarding power cords.I have a Blue Marble Audio, Signal and Aural Symphonics Missing Link. The stock power cord sounded better then the Blue Marble and about the same as the others. The BM cord bested many other PC's I have tried on tube amps as an FYI.

Soundstage extends well beyond the sides of the speakers and the center is filled in nicely. Yes, like most good tube amps the room is filled with music. I never feel as if the notes are firing out at me from the speakers, like some SS amps. I am saying it sounds natural and life-like.

The amps greatest attribute is it's wonderful tranparancy and detail. I like the amp more and more the longer I have it.

Your remarks would make it seem that you have been pleased with Scompracer's fix. His methodology seems pretty complete. What did you experience with this? Did all of the induction noise seem to vanish, or was it simply reduced?
Hello Jeffcott. Thought I'd join in here again as I too am very interested in the McAlister amps.

I spoke at length, on two seperate occasions, to Peter McAlister, and one of the questions I brought up was the "transformer buzz" issue. He assures me that this minor problem has been totally addressed in all models henceforth and will survive even a shipping mishap similar to Grannyrings, without having the transformers omit any noise.

BTW, thanks in large part to Bill's (Grannyring) excellent well-penned review, I am putting my money where my mouth is and have placed an order for McAlister's mono-block version of this amp.

Lastly, I want to point out that Peter McAlister has been a real pleasure (and braintrust of circuit knowledge!) to deal with thus far -- will keep you "posted" with my own impressions, in a month or so when I get 'em!

Thank You! for chiming in. I too, have communicated
with McAlister about Monoblocks. They are a nice looking
pair. I will email you offline with my contact info.
Please let me know what you experience when you get them.
Denf & Jeffcott. As an FYI, yes the mechanical noise or buzzing of the power supply is gone! Never any noise through the speakers so all is very quiet. Noise vanished from a position of 2 feet away. Non - issue.
How does this amp compare to the Thor amp you used to have?
Nathanu, very interesting question. I no longer have the same associated gear for a true comparison. I do have a general sense however. The Thor amps are $9,500 as you know. I find the Mcalister to be more see through transparent with more air and sparkle.

The Thors throw a larger stage and have a more "beefy" sound. Thor amps are very organic sounding. The Mcalister is just as fast and has that same jump and wonderful pace to it.

Bottom line is this $1100 amp does not take an overall back seat to the Thor in sound. I know this sounds nuts based on the price difference, but I call it the way I hear it. Thus far the only amp I have owned that is better overall is the Mcintosh MC402.

Thor looks a whole lot better and is built to last. If looks are important, them the Mcalister will come up short.
I like the DIY look however.

I am considering getting the monoblock amps custom made for me by Mcalister. For now I keep trying other amps to A/b against the Mcalister. My very good Marsh a400s amp is bested by this baby and I soon have some Monarchy SE250's coming for audition. I used to own the SE160's and loved them. I am sure the SE250's will be stiff competition. We will see.

I like to always have two amps on hand for fun.


Don't know if you can help but I am interested in McAllister's creations. My current system is...
Kolida JD 100 CDP
Eastern Electric MM pre
Custom tube pre (listed on A gon at present - hate to part with it)
Consonance Ella tube amp
Ed Schilling's the Horn speakers

I am considering the Nelson Pass F1 SS amp which is supposed to be a wonderful match for the MM and the Horns but...I have enjoyed what tubes do and these seem to be a bargain.

THE custom pre I have is "fleshy" and smooth with good bottom end but lacks the airiness and staging of teh MM. I would like to retain the attributes of the MM and perhaps find a different amp that would provide for more fullness and bottom end.

Any thoughts you may have would be appreciated.

I would call Pete of Mcalister as he makes many amps and custom amps. I am sure he has the perfect amp for your SET system. His amps have great bottom end and have SET like transparency.

The PP150 is much more powerful then you need, but would sound great. Should you go to more power hungry speakers you will be all set.

Thanks BIll,

I spent an hour on the phone with Peter today and he was great to talk to. Certainly knows his stuff and was honest and forthright.


Thanks for the thorough review, and I appreciate the fact that you’re able to provide this in the context of the extensive list of amps you’ve owned. After reading this, and spending a significant amount of time on the phone with Peter McAlister, I’ve placed an order for the PP150S.

I’m also driving Dali’s, though mine are the Grand Diva rather than the Grand. If you get the monoblock SETs, I would be interested in hearing your opinion on how well they manage the Grands. I had considered going that route also, but Peter felt that I’d be better off with the PP150S considering that the Dali specifies a minimum of 50 watts into their 4-ohm load Grand Divas.

Also wanted to add, the bias pots are on top as a standard feature now.

Thanks again.
This amp has been traveling into some other systems as well as going up against some very nice Monarchy SE250 monoblock amps in my system - $5000. Overall the Monarchy amps win out as they image better and have a sweeter midrange. They are also much more powerful.

On Merlin VSM SE speakers the Mcalister amp is fast,dynamic and transparent. The mids were a little thin for our liking on this speaker. The Mcalister amp seems best suited/matched to warmer, full bodied speakers such as my Dali Grands.

I am always listening to new gear and will soon try Nuforce 9.02's.
Hi Bill. Have you tried some NOS tube rolling in your Mcalister? I would be curious how that would affect the overall sound.
No I have not tried using different tubes. That could prove interesting.

But then again, you might want to check with the designer before tube rolling. He might have voiced this amp with the tubes that came with it,maybe?