Massdrop x Eddie Current ZDT Jr. (Official Thread)

Don’t forget to tack on another 0 to the price. Otherwise it’s too cheap to be good.

 

Below are some off the cuff impressions as I sit soaking in the tubey goodness of ZDT Jr. BTW, I have a unit with the hum issue - it still performs nicely for a variety of musical genres.

For the record I find my chain of Optical - Modi Multibit - ZDT Jr. + GE Jan tubes - HD650 stock to be an exceptional display of resolution even as the gear is modest compared to the setup in my office. You really get a bit of that magic with the ZDT Jr. and the HD650.

First of all one of the most unfatiguing sounds - even with a Modi MB which can seem harsh from some gear while being rolled off and imperfect in the treble and lows. But ZDT Jr. Does well and actually scales with Gungnir Multibit. I just find it does so well with my Modi that it makes an adorable looking setup together. It is my bedside - chillout rig!

I honestly think ZDT Jr. puts the Bottlehead SEX 3.0 (C4S) to shame with its lack of fatigue in the tone. I remember using both of my current DACs and all three of my current fullsized headphones with Bottlehead and I know that harsh treble glare and relative lack of coherent soundstage from the SEX.

ZDT Jr. provides natural staging with great depth. There is an effect of notes/musical instruments heard through the amp having a "blob-like" soundstage (involving a solid centre image, hard left and right, but missing information or location of instruments naturally within these reproduced spaces in audio recordings).
However this limitation is a very subtle thing and nothing that really keeps me from loving this amplifier.

Having used this amp since September, in various configurations and with comparisons to various gear... I feel confident in saying that this is perhaps one of the best bang-for-buck amplifier I have heard. I gave a glowing review for my SEX amp once but today this feels like a joke.

Seems I have learned to better listen to the sometimes subtle effect of source/amp components... but I remain aware that the mind can be amazingly malleable.

I can say that the tone is good and the treble has great articulation which I identify as a "relatively honest," sonic presentation that is transparent to the source in higher audible frequencies but at the same time without causing undue fatigue.

Dynamic range seems great. The mids of HD650 really standout in this chain of components with the ZDT Jr. in particular seeming to bring great (micro)dynamic range and contrast in the volume of notes which is tested with audiences clapping and recordings of playing the piano. Just a few personal quirks involved in listening to gear (if i manage to pull myself away from the music!)



These glowing impressions of ZDT Jr. therefore come from limited trials with some unscientific A/B along with repeated recreational musical appreciation sessions. I also use binaural recordings and tones in testing gear, mostly transducers/the cans themselves.

Good headphone pairings in order of my preference: HD800 low S/N ~1500, HD650 new Oct, 2017... Focal Utopia

Bad pairings: LCD-4

I hope this info helps someone decide if the amp is right for them. This is unscientific and my personal impressions with heaby bias for tube sound - particularily smooth while articulate treble.

 

With such a glowing review, I'm surprised you wanted to sell it like 2 months ago...

Perhaps a Canadian loaner is in order. Well only Alberta, since apparently we're separating from Canada soon.

 

Comparing ZDT Jr. and ADI-2 DAC's amp again after more listening (with my EQ'd and non-modded HD800) - they sound surprisingly similar. This is a learning experience for me, since the ZDT is my first full-on tube amp. I'm basically learning, once again, how the tranducer does most. But yeah, there's more shades of grey.

Through ZDT Jr. vocals sound less harsh, sweet and nice overall and bass is more a mid-bassy thump than the snap out of the RME. Highs (cymbals, vocals) are the most prominent difference right now. On ZDT they are very smooth, lacking loads of harshness on bad recordings. Basically the ZDT is more about the sweet mids, steering clear of subs and smoothing over lots of the nasties in the highs. Kind of a very pleasing reversed V-shape at the extremes.

There certainly is a difference SS-wise, but most rock/metal music doesn't show it too clearly and that "stage" is very artificial anyways through close-micing etc. I'm hearing stuff playing a bit wider L-R wise. It's not a major issue for me.

For my kind of compressed / artificial -music using HD800 the ZDT Jr. is a nice flavour and a very pleasing change of pace for many a tune, but far from a necessity.

A well implemented EQ does way more with a good transducer like the HD800 for a simple dude like me.

P.S. As I've said before, I'm hearing that hum too. It doesn't bother me as I normally listen to some noisy music. But for re-sale value alone this one's going back. For a "hi-fi product" it's most disappointing to have this hum not because of actual listening problems - it's the thought of it that nags at me once I put the amp on in a silent room. I hear it. A product with such a specific purpose in the audio chain it simply shouldn't perform such evil deeds.

 

I appreciate the offer Cee Tee. Its only fair to your company that I enjoy the product you sent me in good faith. I know you will make it right if there is an issue. I regret making such a down remark about the product especially when it's being represented by someone who has demonstrated a lot of integrity in their dealings.

 

Yeah, with -90 SNR some hiss/hum is guaranteed. Probably a compromise of tubes and low cost.

 

Massdrop's e-mail states:
"If you find the hum of the amplifier noticeably louder in one channel, then your amplifier qualifies for replacement. Note that all tube amplifiers have some level of self-noise but it should be consistent between the right and left channels."

Yeah, my hum isn't really louder on either channel - well maybe the left one a bit. Should I still go for a replacement?

God damnit, this is the last thing you want ordering from outside US - I can already see the hassle with customs etc.

 

^ I recommend that you send it in...sorry for the hassle!

 

Where to send replace email? Or just reply ZDT update mail from masdrop? Thanks!

 

Thank you!

 

At this point I am planning to keep this amp around for the long haul as i love it with HD650k. Already have a couple pairs of backup driver tubes and would like to have some power tubes on hand in case as well... don't want anything fancy just something as close to stock as possible, so i just want to look for 6N24P's correct? Has anyone purchased some they could recommend and from where? Would prefer some place other than ebay but will go that route if need be. Would these be acceptable? https://tubes-store.com/product_info.php?products_id=52

 

Yes, that's the right type. The same as what you can buy on Ebay. I've done a lot of tube rolling in this amp during the last 6 months. After the humming issue will be over for everyone I plan to write a detailed report of my findings. Until then here are the most important ones:

• Rolling the power tube makes as big difference as rolling the driver tube.
• The different vintages of Voskhod's might have different sound. The ones that came with the ZDTJr are old, made around 1970. I found them better than the newer ones (>1980).
• The factory default tubes are a bit lean and bright sounding. It suits well for the HD650, but brighter headphones pair better with warmer tubes. For those who live in the USA, I recommend Tesa ECC89 from The Tube Center. I find those to be great with the HD800. TTC also have ProComm ECC89's for the same price, which are even brighter than the Voskhods.
• These NOS tubes act weird in the first two or three days. Give them a 100 hour burn-in before judge them. Don't worry about the life expectancy. The ZDT Jr. keeps them fairly cool, so they last very long.

 

I'm so old that I studied tubes at the University

Briefly about the processes in the first time of the tube.
When heated, dissolved air is released from all the elements of the tube.
The gas absorber takes time to absorb air molecules and increase vacuum.
And the second parallel process. An active layer is formed on the cathode surface.

All new tubes require some time for training

 

Apologies if this was answered in the thread already, I have read many pages but did not see it mentioned.

I already have the MCTH and have woken it up with an lps, but I was looking to get one more amp.

Does the ZDT jr invalidate the MCTH? I don't have any planars and my MD+ doesn't do that well with the MCTH anyway. The hd800 are next on my hit list though while I also have the hd600 which I'll be keeping around. I was considering the THX but I'm not sure solid state is the way I want to go anymore..

 

It depends on your musical preferences and headphones. If you get/have HD800, then ZDT Jr is a great budget choice. However, finding a ZDT Jr is probably challenging. The MCTH is a different kind of budget amp and does not have the mids, tonality and imaging of the ZDT Jr. I really liked ZDT Jr with acoustic jazz, but preferred MCTH for more electric jazz, rock, etc. All of the mid-fi amps from Massdrop are good value gear, but is your goal to have a collection of these amps or should you save for a better amp?

read more here:
https://www.superbestaudiofriends.o...erbaf-cheap-tube-amp-guide-1200-or-less.2796/

https://www.superbestaudiofriends.o...s-for-the-sennheiser-hd800-2017-edition.3408/

I would also post questions like this in the general advice thread.
Also it is helpful if you go into your profile personal details and create a gear list and musical preferences.

 

Thank you for your detailed response. I haven't considered getting any end game gear since I won't know where I'll be in five years, so I prey on finding things that people vouch give incredible value for the price. I'm usually lurking, but I should fill out my profile more

 

I decided to try the TESA (Phillips) ECC89 tubes in the ZDT Jr. They haven’t arrived yet. Can those of you who have tried these comment on how they affect the sound of the amp? I was wondering why these tubes have been recommended.
Thanks.

 

Not sure either. I usually only use gold pin tubes in my amps as the found the grey pins to be noisy. Hope this isn’t the case here though