Full review: Audio Research based ZeroZone PRT-13A balanced tube preamplifier (PRT13A-BAL)

[@jobertvangool9961]

As a matter of fact I am listing to it as we watch this video. I have the big bank of 8 capacitors laying around, unfortunately they are 15uF instead of 12uF, would it affect the characteristics in a bad way? There are 4 real nice oil/copper 0.33uF replacements on its way as well. This preamp is fully balanced, and that was why this amplifier was indeed my choice. Love you came back with a more detailed version of a review of this preamp, thank you! 👍🏼

[@dendres95608]

I think the oil/copper caps will make a big difference.Done some mods in the past and that is the way to go.

[@k4syx]

I cant unfortunately tell. I think there is a store that has diagrams for that construction so there may be your answer. I would try that if I had them here anyway, its a quick job to replace them.

[@hugoaguas6719]

Using 12uF or 15uF would not make any difference.

[@jobertvangool9961]

@@hugoaguas6719 thanks you very much, I did find the schematics and the suggested value for those capacitors was between 10uF and 15uF. Can’t wait for the 0.33uF Miflex KPCU-01 to arrive and start!

[@dendres95608]

Thanks for your review!

[@karelhagemans8694]

Thank you for clarifying the issue regarding the CE certificate.

[@yellow_noise3]

Is it CE Mark or China Export logo? They look almost identical

[@k4syx]

@ And again thats no coincidence :) What is imprtant here that CE can be done via self certification - declaration of the manufacturer. Soooooo... I would put that much faith in it anyway.

[@taxicabriviera1831]

Hello. That's always a pleasure to watch yours videos. Thanks for that👍 It would be so Nice if you could test the preamplifier MBL 6010D (Master version 9.3)? Thanks again 👍

[@k4syx]

Thanks! I have that one in my shopping cart on Ali. I will get it at some point, but for a while I've stopped my purchases as I need to do reviews for all the stuff I got last year :)

[@FDKAUSW]

Tom, thx. For Ur Video. If I see this here and Ur Video to the Cary PerAmp. And I see Ur emotion I know what I like to buy. And this PreAmp has this Bad Volume-Poti on Board too. Also that I not able to hear RCA over XLR is a joke too but however some People buy this item…😅

[@k4syx]

Exactly, Cary is another league!

[@FDKAUSW]

@ and the Marantz 7 (same producers) is a little bit more bether as the Cary it have both. 😎

[@D1N02]

This will remain on the wishlist for reference. I had found other balanced tube preamps. But more expensive than this. One called LEADAUDIO ARCLS22 and another Suqiya mp400.

[@k4syx]

I have both on my list as well but as you cay this one is the cheapest from the bunch. And it looks so good too :)

[@roa5359]

Thank you

[@mddawson1]

The CE has two meanings. From the web: "The difference between the CE and China Export markings is so subtle on paper that consumers can often confuse them without even realising. Despite the great similarity of their appearance, it’s important to understand that they actually have nothing to do with one another. While a CE marking is a declaration by the manufacturer that a given product complies with European regulations on marketing and selling products within the European Union, the Chinese CE marking is simply a way of indicating a product was manufactured in China."

[@k4syx]

Yes, and the China Export mark is "accidentally" looking almost the same, with the difference being slightly larger spacing between C and E. Doesn't really mean much though when CE can be just declared with no independent testing

[@2011FM]

Hi Tom. On your 12:20 duration time review, you should have mentioned it as a 6922 tube being a general substitute for Siemens ECC88. Not a 6977.

[@k4syx]

Yes it's 6922, if I've said 6977 then either my English got weird or my mind was wandering somewhere :) Sorry, yes, it's 6922!

[@manosmul6827]

Thank you for all of your videos. In your opinion, which non-tube power amplifier with a 'warm' smooth but 'tubey' sound would you say is best value for money? And what seller on Ali Express would you recommend? Thanks again.

[@k4syx]

That would be either C245 or C2860+, the first one being more relaxed and tubey. I tend not to recommend shops, rather then I prefer to recommend specific offers as the devices I test and those in other shops may look the same on the outside, and be slightly different on the inside. So to be sure, I recommend specific offers that I know are for exactly the same units. Look for C245 and C2860+ links in the review video descriptions.

[@mddawson1]

You might be able to reduce the volume control motor noise by soldering two 0.1uF ceramic capacitors, one connected from each motor terminal to the motors case.

[@k4syx]

Thanks, will do that, it's 15 minutes job. I need to take a look at my parts bin, there's strong chance I have some 0.1u there

[@mddawson1]

@@k4syx Not sure what voltage. If it isn't printed on the motor, you should be able to measure it when changing volume.

[@JoaoPereira-os9wc]

Olá ! Tenho Matisse pre-amp com condensadores de óleo Zero Zone e tubos 12AT7 12AX7 EH e Tubo retificador 6U4N-EB soviético e toca muito bem. Foram precisos 150 horas para queimar mas agora está muito bom

[@k4syx]

Thanks for sharing! Can you post a name of that preamp here so I may look it up? Unfortunately yt will cut direct links :(

[@annebokma4637]

That sure is a nice balance between balanced and unbalanced in and outs 👍 and black 👍👍👍 shame the single ended in doesn't go to the balanced out. No bueno for my use case

[@k4syx]

Yes it looks very very good, my main and biggest gripe is the sound quality (now, we'll see about that after recap)

[@annebokma4637]

@k4syx yups waiting for that content to drop 👍😁

[@danshapiro1195]

You indicated you ordered the version without tubes, but I was surprised to see the tube section.

[@thegemmellfamily9641]

see 12 minutes in the video.

[@k4syx]

Yes I've explained in the other comment :)

[@michaelbooth6007]

Just ordered the Dac 05A11 PCM1794X4 OFF Sunshine Audio but which is offered on this channel. They offer it in 230v which is better for UK use.

[@k4syx]

I've seen that one but I havent got it - Im not sure I will like the sound, I love musicality but not at the expense of detail (and reading the opinions on it I get the smooth and smooth vibes)

[@Geoduck.]

Replacing some caps and tubes in this open case looks fairly easy. However 8 each quality 12.0uF film capacitors is not cheap as are the four tubes.

[@k4syx]

Yes it's easy, I've already looked at some caps and it will be like 100usd for Jantzen Standards, these are not cheap due to capacity and there is a lot of them...

[@jacek_r2701]

Those Samyoung (Korean) capacitors, if not fake, would probably be quite reliable (5000h @ 105*C).

[@k4syx]

Yes I've seen them in some beefy PC PSUs. I think they are real, they are cheap as they are.

[@jacek_r2701]

I've actually bought some of them to recap an old Windows 98 PC (motherboard and PSU), just for fun...

[@chinmeysway]

i thought this was a speaker amp. why is there so so many caps? that’s wild. esp for a preamp like what is the concept in this design?

[@k4syx]

I would say (without tracing the pcb) that these are in parallel to build larger capacity on cheap (MKPs tend to get very expensive and very large for higher values)

[@hcr2ligna83]

I bought this one over the Cary purely on looks.. if only the cary just wasnt so dang ugly😅 oh well.. lets hope those 8 mkp's are the problem🤞mine will come Tuesday Do you already know wich mkp's are best for this? I only have some experience upgrading speaker filters.. any elco gone is always an upgrade 😆 all the knowledge i have haha

[@k4syx]

My choice would be either Jantzen Standards or something similiarly priced from Mundorf - to stay within reasonable budget, at least for the first try. If you will replace them, please do share your thoughts on the sound quality, ok? Im still undecided if I should order caps or just leave it like it is :)

[@hcr2ligna83]

@@k4syx I bought mine with the standard tubes, so i dont know how that will effect the signature but i will report my thoughts. Im really hoping it wil atleast be an upgrade to my emotiva pt1 😅

[@hcr2ligna83]

​​​@@k4syxi got mine today! I have a different one, my mkp's are all pointing the same way😆 just hooked it up... Even without break in it seems to have everything, Anna Lee - Buddy Guy is currently playing, i hear him breathing all the string touches are there. Maybe this is the first ever amp that only sucks after break in..😅 i sure hope not Have you tried it with the A1 fidelity? From 800hz up thats what i have connected I do have a slight his in the right speaker and the volume control coming out the left😆 but i dont mind this at all, the music is whats important, + my speakers are 98db so there already was a noise thats still louder then this new little noises

[@hcr2ligna83]

​@@k4syxwell after about an hour of running the tonality got awfull very harsh and forward it stayed like that for many hours.., so i got very very nervous started making excuses for what was worth my money and accepting i might need to send it back and cut my losses😢 But! Today i came home from walking the dogs and thought.. hey.. whats that, it was running for 44 hours then, and it actually started to get some tone balance. Now its been running for 50 hours and im starting to get very impressed.. the placement in space is unlike anything ive experienced. The dynamics are crazy good even on low volumes the sound stage stays huge. Im really starting to think there must be something wrong with yours😅 im no stranger to high end gear..your opinion on gear is the closest to mine of any reviewer i know off🤷‍♂️ the pre amp i got is very good and getting better by the hour Oh and btw, when Gabster bought his one the stock tubes where different ones, he had softec ore something.. i dont know if im spelling this correct but thats what he said in the start of the 2nd video

[@hcr2ligna83]

​​@@k4syx I really tried to find something wrong with this pre amp.. I expected to find something after your review, its been a rollercoaster 😅 im hearing so much dynamic range it was hard to believe there wasnt something wrong.. certainly with a biased mind thats expecting something terrible. I have autism change is always hard for me even when positive and my hearing is very very sensitive. Now i have finally settled a bit and well the truth is i just cant stop listening, this thing has got me hooked! Im exploring whole new realms of music i never thought i would like. 🎉 Im really feeling Gabsters opinion.. 80% of the sound for 5% of the price👌 could not be happier I have seen some people say the orientation of the MKP's might matter.. i dont have the slightest clue of the theory behind this, but mine are all up side down when you read Zero Zone on the print. The 8 big ones but also the 4 smaller ones near the tubes all have the same orientation, maybe something to try?

[@bertroost1675]

I must say it would be nice if one of these Chinese manufacturers used a nice stamped chassis instead of the usual heavy cut metal chassis, just to mix things up a bit.

[@annebokma4637]

I want gear milled out of a solid block of platinum.. still paint it black though 😂😂😂

[@k4syx]

I have one preamp lined for a review with that kind of cheaper chassis. It feels strange to hold it in my hands, it seems fragile compared to the rest of the panzers ;)

[@eugenefudge3685]

Why

[@eugenefudge3685]

I would like to connect a subwoofer. Is there any AliExpress preamp that has sub out put

[@BaileyWiggebutt]

Hopefully you are being sarcastic.

[@Spicycomment1]

Hi, if i had to buy one, only one amp from China, which one would you recomeng highly

[@k4syx]

Cary SLP 90 or C2860+ (depending on your budget and if you're tube or solid state guy)

[@Spicycomment1]

@k4syx thanks, but these are preamps, . What about clone maps, which one would you recomend if i had to buy one from china

[@declin_ro3823]

would this work better with dartzeel clone than the other the tube preamp ?

[@k4syx]

Nope. As I've mentioned in the review, Cary is better

[@thomaswhitestone8807]

Maybe it could benefit from small by-pass capacitors???

[@ChicagoRob2]

I was thinking .1uf Jantzens.

[@hcr2ligna83]

​@@ChicagoRob2 What is a by pass cap? And where do you place it?

[@k4syx]

That would be the cheap way to test if the fault lies with them. Good idea, I may try that. I would get something that has siginificantly warm signature and test for changes, if there will be any, then we would have the culprit. Thanks!

[@k4syx]

@ thats adding another cap in the parallel to the first one, Its a trick for tuning the sound characteristic without replacing whole big original cap as it may be expensive. Sometimes its also done to lower the ESR or the pair.

[@danshapiro1195]

So as I understand it now, this is a tube preamp, and you decided to not order tubes from the manufacturer.

[@k4syx]

Yes exactly, I got the one without tubes included in the delivery

[@cesarjlisboa7586]

Tube pre-amplifiers you must to burning at least for 1 week. Better burning before you re-cap

[@k4syx]

Yes it had two weeks (no kidding) of burn in before any listening sessions...

[@cesarjlisboa7586]

@ capacitor’s from PSU playing very big rules, as well.

[@roberthart9886]

hard to imagine it's < $300

[@chinmeysway]

? it’s not. he got a big discount

[@k4syx]

@ that was 30 USD coupon - not that big, but still something. It still is cheap if you'll order version without tubes as I did

[@k4syx]

I needed to touch it and see if it was real ;)

[@matytinman]

Please allow me to go off-topic, but I think it is very justified. I just shared the vinyl rip of the original pressing (the best sound I have heard from this legendary album). Keith Jarrett - The Köln Concert (1975) Vinyl x2 kzbin.info/www/bejne/eYO0cmWhga-deLc

[@k4syx]

No problem ;) Take a look at the comment there :)

[@carstenrombach2218]

[@doofwop]

No tone controls no dice. So sick of the 'audio fool' community taking my tone controls, my loudness button, and my power meters away from me with their purist propaganda. You audio fools don't hear miracles that nobody else hears despite what you might think. 2 channel hifi has been ruined by audio fools.

[@chinmeysway]

true i share your sentiment but this is just a preamp. you don’t have an eq? they are best for tweaking tone

[@doofwop]

​@@chinmeysway for me, EQ needs to be part of the preamp's job.

[@neokeeboon3325]

Thank you as always for your time & effort Tom. Lookin forward to your review for CAT sl1 & dual transformer version of NHB108. Cheers.!

[@k4syx]

Thanks! These are coming to my channel!