Owner Testimonials

Amod P., Canberra, Australia
Dear Jon:
Firstly, thank you for your friendship and presence – these are much appreciated!

The Gems arrived yesterday as I said to you over the phone after a long and an anxious wait 😊

The delivery person was able to lift them out of the truck and place them at my doorstep without any difficulty. I opened them with the cartons standing up so it was easier to slide them out (carefully of course) as opposed to picking them up from the cartons. As indicated over the phone, it might be useful to place a red dot or some other visual indicator to denote the top (i.e., the top of the speaker) so that the carton could be stood up the right way for the speaker to be taken out vertically. Also, it might be worth considering placing labels like ‘Fragile’ or ‘Handle With Care’ or similar – but these are mainly for the sender’s and the recipient’s peace of mind!

That said – the set up was a breeze and I had music flowing out of the Gems in under half an hour of their arrival, which was probably a function of my childlike enthusiasm (also foolishness 😉).

As you know, I mainly listen to Indian classical, and some Western music (vocal/jazz) and some World music too.

My associated equipment is the Tascam CD player, Benchmark Audio DAC, Linear Tube Audio (LTA) preamplifier (this is a zero hysteresis, output transformer less valve amp) and a musical fidelity power amplifier. The analog sources are a Rega turntable and a TEAC A2300SX reel to reel machine. The integrated amplifier is the Cayin KT88 valve amplifier.

I played some music over the CD (pre+power amp) to begin with and get a ‘sense of the sound’ so to speak. I am not going to engage in superlatives, but let’s just say that I was ‘engulfed’ in the ‘sound of the music’! I will supplement this review of sorts with my experiences of playing music through the valves, which I am told (and I have read) is an altogether an experience on a different level.

The sound is engaging (not fatiguing), not least because of the sound staging in my opinion. The Gems are an unforgiving (read accurate) speaker. So if you play well recorded material, that’s exactly how it will sound (i.e., they will bloom to sonic nirvana), and equally if you play not so well recorded material, they will embellish those flaws quite faithfully too 😊. Thankfully, the material I played was very well and professionally recorded.

Here I must make a comment that should be appreciated by audiophiles – with the Gems I was able to not only hear the music, but ‘see and feel’ it as well! Again, this might seem to some as an alien concept, but one has to experience it, because music, in my opinion, is what feelings sound like!

I think it is necessary to at least cursorily mention the so called standard attributes of a sound reproducing device: the accuracy, the sound staging, the presence and lastly but by no means the least, its visual appeal. Given that these are an open baffle design, it is ‘baffling’ how ‘open’ they sound – ideal positioning is about 3’ from the rear wall and about 6’ between them (this may not always be possible due to space constraints). But the good news is that they are largely independent of placement!

Their ability to ‘disappear’ is phenomenal, and so is their accuracy, and that what adds to the ‘presence’ as I referred to above. The two opposing concepts of presence and absence are almost like a Yin-Yang 😊. I chose the red colour as it contrasts well with the colour scheme of the lounge area where they are set up, but I gather a multitude of finishes are available.

The Gems are shipped assembled and contain a modified Tang Band W8-1808 full range driver (made in Taiwan I gather) and a bass driver from Eminence USA plus an improved crossover network designed by Jon himself here in Australia. There are ample reviews for both these products and one can read them to get a sense of their abilities, however what they do in tandem with this proprietary cross over is nothing short of magical!

Here there may be a tendency to compare the Gems visually to the Pure Audio Project’s Duet 15s – but not having heard them in person (except in YT videos), I think the similarity begins and ends there and each product has its own place in the musical world order and no further comment will be made as it is irrelevant and unnecessary!

In any case, this piece is an unsolicited one and I am very happy to demo these to anyone who is contemplating an OB speaker in the ACT or its surrounds. Mr. Desensi – you have excelled yourself!

With thanks and very many good wishes.

Peter P., Rostrevor, SA 31 Aug 2021
Listening to the pre now, wow I thought it was great with digital! Just put on some vinyl (OAD UP1 Phono) and it just went up another notch! Much better than my Jeff Rowland Capri V2 I had. Very happy thanks.
Cheers Peter.


16 Sep 2022
Hi Jon,
Hope this email finds you well. Having a critical listening session and still blown away by how musical the system sound. What is most impressive is how linear the amp is from top to bottom. The amp just excels at rendering the deepest bass notes with such control and mastery. The soundstage is also incredibly expansive. The Vajra just has a very impressive musical presentation. So glad I bought this amp- I've never heard its equal!
Best regards,
Dwight B. Wellington, NZ


15 June 2022
Hi Jon,
Been meaning to send you an email for a while now. Continue to hear subtle but definite improvements. Listening to Into the Labyrinth at the moment and when I close my eyes it certainly seems like the real thing- being in the same acoustic space as the Dead Can Dance- very realistic without any hint of electronic haze just the music presented as very lifelike. There are times when I am just listening passively that I actually get startled with how realistic my system sounds- very cool!
I'm curious if there are others out there raving about the amp- might be a bit tight with inflation; I suspect money is a tad tight- but I'd be surprised if you could keep up with the demand!
Best regards,
Dwight B., Wellington, NZ


10 April 2022
Hi Jon,
Just a quick note to say the sound quality has taken another significant leap. Better resolution at the back of the sound stage and instruments and voices more 3-dimensional and occupying their own discrete space.

You had asked me before about the difference between the Krell and this amp. I would definitely say The Vajra is much more neutral the Krell is more fuzzy but a more "tubelike" euphonic. There is no doubt the Vajra sounds more "natural" and "right".

Just talked with Phill- interesting that you are working on some speakers- you are a man of many talents.
Yes, really enjoying my system and the level of musical engagement- big improvement.
Cheers,
Dwight B., Wellington NZ


19 Oct 2022
System continues to sound fantastic listening to DCD Spiritchaser- everything presented viscerally, I love that didgeridoo at the beginning of Song of the Stars.
Cheers,
Dwight B., Wellington NZ


To: George on StereoNet 6 May 2021
I haven’t put anything up against the OAD pre for comparison since I’ve owned it all I can say is it’s by far the very best preamp I’ve ever heard, I’ve owned well regarded expensive pre’s over the years the only one that I would claim comes near my OAD pre is a Transformer Volume control passive pre, the Consonance Reference 1.3, this device was something very special, airy open and dynamic with guts traditional passive pre’s are not (never) endowed with, it has a 0 or db gain option I tried 6 once and never bothered moving off 0 again. This pre murdered everything else...then the OAD entered the equation and after a week or so took the R 1.3 to the cleaners producing better everything . This was a pre that I thought to be a lifetime keeper. In discussions with Jon a while back he did tell me the new pre would be quite a bit better than the model I have! something I didn’t really want to hear, (the news not the pre) so if I was you I would hang on and see what happens, it shouldn’t be too far away until you get your hands on it George.

I had a years wait for my preamp to arrive in this time I used the R1.3 for a pre with excellent results, OAD pre was OK but not earth shatteringly better this took around a week, I thought I'd add this just in case you don’t think the new pre is that good when you first get it, trust me it will get lots better with some up time. it will stabilise to perfection a lot sooner than the power amp.

I am now using the new stand alone phono stage, I’ve had in in the system for a couple of months, like the rest of this guy’s gear I can’t justify the price tag considering the quality it should be at least three times the price he’s charging it’s so very good, I have the phono card in my preamp and always thought it was great but like the new preamp the new phono stage really is quite an astonishing upgrade in sound quality and something I would highly recommend, apart from the audio build quality and design also breathtaking.

If I could just say that digital sound your hearing may not be the fault of whatever your using as a pre atm, I probably would have mentioned to you previously the OAD power amp was terrible first listen in fact I was broken hearted wondering how to tell Jon his amp was not very good and I wouldn’t be keeping it, it sounded like you would think a solid state amp would sound hard bright early digital it took some time to burn in, about a fortnight before it became an enjoyable listen not long after it totally humiliated my very nice 805 fifty watt single ended monoblocks and just improved every listen for over a year, YES over a year. Take my tip and run the power amp as much as you can, I ran mine at low gain using a digital player on repeat for a fortnight, the other tip is never turn the pre or power amps off, they take a day to give top quality from cold, I have a mate that turns his OAD off and still thinks it sounds fantastic but I know from experience leaving the gear on is best.

Cheers, Phill, Ballarat, VIC


18 Dec 2020
Hi Phill,
Yes, the power amp is very impressive, and I’ve asked Jon to pencil me in for the new preamp when it’s available.

What I have noticed with the power amp is that It takes about 30 – 40 mins to warm up to get to its peak, and there’s a big difference between that and when it’s cold. The first two months was settling in time, and now it’s very good. I certainly won’t be looking around for anything else.

The hard thing for me at the moment is to try to get my head around what the OAD preamp might sound like, as there can be so much difference with any pre’s. I’ve tried a couple of different ones with my gear and some are OK, but that’s about it. Time will tell I guess.

I just had a friend over with his Jeff Rowland pre and thought that it was a little dull (he said it was ‘smooth’…). I also found my Benchmark DAC3 far more detailed and dynamic but lacking a bit of tonal richness with the rest of my gear. I have taken some assurance from your opinion that the OAD pre was better than the Accuphase C280 I sold you. Jon assures me that the new preamp will be better again than the original. Interesting…

Cheers, George, Rostrevor SA


Hi George,
It just occurred to me what a small world it is.

Jon De Sensi has been a good friend of mine for almost twenty five years he visited us yesterday and did a crossover mod on the open baffle speakers he built for me and noticed the Audia Flight player told me a guy called George that owned Audia Flight gear bought an OAD power amp!!! My response ' he's not from Adelaide is he'. he said yes And the penny dropped.

Here's a heads up, you won't find a power amp that can get near Jon's this side of fifty grand! I am not embellishing in the slightest. Power guts and authority of solid state with the elegant sweetness of tubes in mids and top.

Jon and I have a mutual friend that owned AM Audio 833s monoblocks costing thirty grand, after I evaluated my amp and found it murdered the AM Audio 805s monos I indicated he should have a listen too, he did and sold his AM's shortly after. He's owned the OAD for over two years now and still raves about it every time he calls me.

Wait till you hear the Preamplifier, it's gonna nail you I can assure you of that. Both excellent in their own right but together there's a synergy like a perfect marriage that will take your listening sessions to another dimension.

Regards, Phill, Ballarat, VIC