1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.

    Dismiss Notice

Massdrop x THX AAA™ 789 Linear Amplifier - Impressions Thread

Discussion in 'Headphone Amps (full-size)' started by XERO1, Mar 1, 2018.
1 2 3 4 5 6 7 8 9
11 12 13 14 15 16 17 18 19 20
  1. Th3Drizzl3
    these didnt sell nearly as well as the cth and lcx so it may be a while before they do a drop again prob after the first drop ships out.
  2. CEE TEE Contributor
    Hi All,
    Thank you for your interest. We didn't have as many listening samples as we wanted at launch but knew this would be a great amp and loved due to early prototypes and the graphs during development.

    I just saw some shots of the amps being built...will get a few off the Pilot Run soon and will send a couple of them out for listening impressions.
    We also have some measurement graphs from THX we will post.

    I have an earlier build that I keep on my desk. The amp is surprisingly natural-sounding, but not "dry". Dynamic, powerful, and clean.

    I think we will re-open the drop next month to sell a few that we will have left from the first production run.
    Or, the planning team may open it up for more sales with a later shipping date...please keep an eye out next month!
    Drop Stay updated on Drop at their sponsor page on Head-Fi.
    https://www.facebook.com/massdrop https://twitter.com/massdrop https://www.massdrop.com/?clickid=3QR3Ib27lyA-VkBRJwyGuQJeUkhUQvX5r0tLzQ0&utm_term=252901&utm_content=VigLink&utm_medium=affiliate&utm_source=impactradius&irgwc=1
    cardeli22, FlySweep and Th3Drizzl3 like this.
  3. Th3Drizzl3
    nice i may pick up a second one myself. im so impatient lol i want to hear this thing already haha
    cardeli22 and CEE TEE like this.
  4. Zachik
    I can confirm that THX-789 indeed sound natural and clean. Plenty power, too. For purists, or people that love very natural sound with no coloration - this one is worth your consideration!
    @CEE TEE - thanks for letting me audition it for a few days :)
    Good decision on re-opening the drop to allow more people in.
    cardeli22 likes this.
  5. twocentsear
    I hope they do the same for their R2R DAC.
    cardeli22 likes this.
  6. alpovs
    The drop is on again. Estimated ship date is Feb 15, 2019. This drop is limited to 480 units.

    P.S. The drop says "328 Ever Sold". I came here to read the impressions. How come there is none? Who bought 328 units? Am I missing something? Is there another thread about this amp?

    P.P.S. Nevermind. I figured the previous drop hasn't shipped yet. I left my flow of thoughts here in case someone else has the same thoughts.
    Last edited: Aug 13, 2018
    cardeli22 and Alcophone like this.
  7. Anarion
    This is extremely tempting... Considering the specs and balanced design, the price isn't that bad.

    Are the current drop page description gain options accurate? @CEE TEE
    cardeli22 likes this.
  8. ufospls2
    This update is for members who joined the drop in March:
    Hi everyone,
    The Massdrop x THX AAA™ 789 Linear Amplifier is making its way through production! We also have some important updates to share about the gain specifications.
    We worked with THX to adjust the gains for the primary use case of the Audiophile community. Previously, the gains were optimized for variance in source output power. Most Audiophiles typically use 2V DAC sources and wish to drive in-ear monitors or hard-to-drive headphones.
    With these slight changes there were some updates to the gain specifications, which we have listed below:
    • Frequency response: + 0.01 dB / - 0.03 dB 20 Hz–20 kHz; + 0.05 dB / - 0.15 dB 10 Hz–50 kHz
    Balanced Output:
    • THD: -130 dB, 32 ohms, 1 mW: 0.000032%
    • THD: -130 dB, 32 ohms, 100 mW: 0.000032%
    • THD: -122 dB, 16 ohms, 1 mW: 0.000080%
    • THD: -122 dB, 16 ohms, 100 mW: 0.000080%
    • Gain: 0.66x , 2.0x, 6.6x (-4, +6, +16 dB), selectable via front switch"

    Damn. The reason I was interested in this amp was the 24db high gain. Going to have to look elsewhere.
    bclark8923 and Alcophone like this.
  9. Anarion
    The reason I'm interested is the negative gain. :p It would make my life much easier...
    Last edited: Aug 14, 2018
  10. AndrewM888
    Hi UFO. The 789 has tons of gain and will still go nearly to clipping with a 2 V DAC. What's your DAC/source rms voltage? And do you use TRS or XLR-4 headphone connection?
  11. AndrewM888
    Exactly. We added the -10dB gain setting because it's awesome for IEMs. It permits a large usable range from the volume pot and a really low noise floor.
    cardeli22 and Anarion like this.
  12. mtmercer
    With the design optimized for 2V inputs, I presume that is singled ended RCA inputs only. Is the design also based on a max balanced XLR input voltage of 4V?
  13. AndrewM888
    No, it's a bit different...

    In gain = 0dB or -10dB position, to avoid clipping internally the max inputs are 7Vrms for RCA unbal or XLR bal.

    In gain = +10dB position, to avoid clipping internally the max inputs are 2.1Vrms for RCA unbal or XLR bal

    The architecture treats inputs differentially regardless of unbal or bal. That's why the max Vin remains the same.
    Last edited: Aug 14, 2018
    mtmercer likes this.
  14. mtmercer
    Thanks for the clarification!
    AndrewM888 likes this.
  15. Anarion
    That would make things much more practical indeed. Since dedicated PC soundcard line-outs pump out 2V (let alone the headphone amp outs), I have always had trouble with the volume control. Currently I'm using low gain on my AE-5 and have set the volume to 18% and I still have to lower the volume further a lot with volume pot (without vol pot I'd have to stick with single digit numbers). It would be the same story with line-out + O2 1x gain mode. While Sabre DACs have pretty great digital volume control but still, this is not optimal...

    Negative gain options are great and I wish those would become more popular.
    AndrewM888 likes this.
1 2 3 4 5 6 7 8 9
11 12 13 14 15 16 17 18 19 20

Share This Page