Iâm not sure if it was done for cost or because of the topology not allowing for it, so I canât comment there, but the amp is not fully balanced and is turned into single ended and then back into balanced I think. It doesnât really matter tbh, but perhaps it may have done something in this situation.
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Since its release in 2018, the Drop + THX 789 THX AAA⢠Linear Amplifier has been praised by reviewers and community members alike. Itâs hard to find a âBest Amp Below $1000â thread without a recommendation for the 789 and the incredible value it offers at $399.
Now, two years after the 789âs initial release, weâre excited to announce weâre adjusting the 789âs market position.
As of April 17, 2020, weâre adjusting the 789âs MSRP from $399 to $299.
This price adjustment is made possible via increased production size (thanks to you) and more efficient material sourcing + manufacturing optimization (thanks to our Product Realization team). At $299 MSRP, weâre excited to cement the 789 as a critical part of the Headphone community purchase progression.
Thanks for your continued support and feedback. We wouldnât be here without you.
IMO not the last word on sub $1,000 amps, but it is at a very attractive price now. Competition is a great thing sometimes.
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I think the main thing its not that it is âthe last wordâ, its that its brought up as a good choice for the value. All the THX amps that are around the same price point are a great value for the performance you get, but there is a whole world now out there under $1000 for every taste.
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I just got the 789 yesterday and have been using the Sennheiser 660s on medium gain which surprised me. Before the 789 I had (and still have) the Liquid Spark and didnât have to switch to a higher gain setting to get the 660s to what I considered to be loud or âpowered properlyâ. Does the 789 on lowest gain setting output that much less power compared to the liquid spark? Is it a placebo? Is medium gain harmful to the 660s?
The 1/4" single-ended output of the 789âs (and Monopriceâs 887) provides 0.7W RMS into 50ohms and the Liquid Spark provides 1.3W RMS into 50ohms. So, under the same load, the Liquid Spark outputs more power than the 789âs single-ended output. It is a completely different story when it comes to the 789âs 4-pin XLR âbalancedâ output.
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No gain options will be inherently âharmfulâ whatsoever. Rule of thumb is using the lowest gain setting possible while still maintaining the desired volume. Low on the 789 is meant for low impedance headphones/iems. Medium is meant for a bit harder to drive options usually 150 ohm+. High is meant for just really hard to drive 300-600 ohm. Youâll also get more power at a given gain with the balanced output as well. Think of the volume pot as the brakes in a car. Ideally you want to depend on the brakes/pot as little as possible while maintaining a proper volume. The gains are like gears in a car. You can hit the same speed in any gear, but some gears are better for a given speed. Gears=gains, speed=volume, rpm=distortion/sound quality. This appears to be the case with THX devices at the very least. Using the volume pot to control volume, cause theyâre usually on the cheaper side and just the way theyâre designed, can sound worse than better designed preamp or dac volume controls because the pot acts as a âbrakeâ for amplifiers that are designed for full power output at any given time.
Ok, so gains are irrelevant. Using a lower gain is preferable because of said volume pot behavior. Nothing will be damaged in the way you are using the outputs of the amp unless you blow up the headphones with too much volume.
In conclusion, we need better ways to control our volumes. Most volume pots suck and are cheap af.
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Thanks for the info. Yup, the volume pot my THX AAA 789 (Spring 2018) started to get scratchy (like my Magni 3), and I believe it is outside its 1-year warranty now 
This honestly raises a good question. Iâve recently gotten into custom mechanical keyboards and started using the windows 10 volume system control through my keyboard rather than touching the volume pot hearing about the THX 789âs volume pot issues. Is something like this an actual good fix or is there something iâm missing?
My understanding is the digital software volume control reduces bits when itâs below 100%. So youâre actually losing audio information by lowering the Windows system volume. There are outboard passive potentiometers that you can add to your signal chain. Schiit makes the Sys which is both a switch and potentiometer. If you need balanced, this exists. Iâm not vouching for the quality of that Polsen unit (Iâve never heard it), just letting you know such things exist.
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I saw that Zeos recommended the Magic dac as well for that purpose. Thank you I really appreciate it.
Theoretically there will always be some impact, but your not necessarily losing bits.
If the source is 16 bits and windows is mixing at 24 bits, you donât lose information until volume is as 1/256th of 100%.
If your using exclusive mode, you are losing bits immediately, since your outputting at the same bit rate as the source.
Volume attenuation is just a multiply by a number less than one, if you have bits to waste youâre not technically losing anything.
That does not mean there is no impact.
Passive volume controls are generally a better solution, I use a Creek OBH12 between my DACâs and Amps, though itâs mostly because of the switching functionality and remote volume control.
But a Schiit Sys or similar will work.
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If I were to use my geshelli labs Dac and use one of the lower voltage options then I assume that this would do the trick?
Yeah. Using a lower dac voltage or a dac with volume control will usually yield better results than using the volume pot of the headphone/speaker amp it seems. Controlling the volume with windows/foobar/Spotify etc is fine but you could potentially lose bits of info.
Hey, this might be a noob question but does plugging in this amp (or any amp) into an ungrounded outlet result in more noise? Should I buy an iPower X?
Picked up the 789 from Drop earlier this week and have been listening to it everyday so far. I swapped out the Schiit Jotunheim and Magni for it on my desk. Iâm still using the Modi multibit DAC and the Loki as part of the chain.
I keep the Loki neutral all the time except for those rare times I need to cut the treble down a bit, or if I feel like adding some flavor on the low end.
The headphones I have are the BLON B20âs (XLR), Senn HD650âs (XLR) and the DT880 Special Edition (SE).
What Iâve noticed with the 789 compared to the two Schiit amps is that it is very clean, almost sterile sounding and I donât mean that in a negative way. It just sounds a little bit less warm by comparison I think, and that is with the HD 650âs and the B20âs. Iâve been swapping between those two all week and this morning I grabbed the DT880âs to try with it. With the DT880âs the warmth that is missing in the other two seem to be present again. Of course, the DT880âs on the Schiit amps were very warm sounding.
Iâve ordered the Geshelli ENOG2 Pro DAC and some Hart Audio XLR cables to go with it. Iâm curious to see how the sound may change with a different DAC in the chain.
The power of the 789 is quite impressive. With the B20âs I seem to keep the gain on I, and the HD650âs on II and the DT880âs on III. Of course that has a lot to do with the impedance of the headphones and XLR vs. SE connections.
Overall, I am impressed with the 789 and pleased with my purchase.
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Given I already have a balanced headphone cable, do I need a balanced DAC for the balanced 6-watt@32ohm channel?
Hi guys I have a HD6xx looking for a amp.
Black Friday week 2020 while I have been âlookingâ at balanced ampâs I donât even own a balanced head phone cable. So its not as important to me today.
However this week we have the DROP THX AAA 789 for $250.
https://drop.com/buy/drop-thx-aaa-789-linear-amplifier#overview 200 mW, 300 ohms
But the new âONEâ is $50 less on pre-order $199 not balanced. Higher single ended at 300 ohm
https://drop.com/buy/drop-thx-aaa-789-linear-amplifier#overview 275 mW at 300 Ohms
But there is the Topping L30 today @ $119 280wW @300 ohm
https://www.amazon.com/TOPPING-L30-Headphone-Amplifier-Preamplifier/dp/B08DNV2K8C/ref=sr_1_14?dchild=1&m=A2Q0JVLI22BSVA&marketplaceID=ATVPDKIKX0DER&qid=1606293354&s=merchant-items&sr=1-14
I also like the option of per-outs as i would like to get Studio Monitors at some point.
What do I do please help.
US based? Schiit Asgard 3 is probably the best solid state amp for 6xx for the price. iFi Zen CAN is probably next best and has the option to go balanced in the future. 6xx really sound best from a tube amp but that also likely doesnât fit your studio monitors as well.
I am actually in South Africa. I was keen on the Atom products I believe IMO that atom has better quality than Schiit. I have heard good things about the THX AAA 789 and the much lower priced Topping L30. Schiit is very popular and have a number great products I have not had too much experience with the brand. The iFi Zen CAN to me is more of a gimmick. I will look at this Asgard 3 but time is running out.
Has anyone tried adding a linear power supply to theirs?
Something cheaper like this?