My BHK Signature preamp is the perfect companion to the DS J, at least in my system. All of this especially if you are running a PS Audio Transport as well as this allows you simple control via one PS Audio remote. For other family members who might like to use the system this simplifies things greatly!
I can tell you from experience that adding even a very modest preamp (like a Schiit Saga) with a different NOS tube, like a cheap RCA GTB, absolutely destroys the preamp in DSJr. Balanced out I find even a bit better/less grey, slightly more clarity.
I love the excitement of new firmware but man, the anxiety that suddenly skyrockets when an announcement is made is hilarious.
I donât usually make statements like that without qualifications 
A passive preamp isnât likely to enhance the output of the DS.
If your system just happens to expect the output voltage range of the DS, and your amp isnât sensitive to ultrasonic noise that a preamp might filter, then using the DSâs built in volume without a preamp is probably best (itâs lossless and if the systemâs matches the DS outputs youâll never need additional amplification, etc.)
Most systems would benefit from a level of amplification that lets a volume on the DS near 100 be about right for the loudest you typically listen.
Some systems benefit from lowering the bandwidth before the amp.
As to whether the DSâs volume or the Preampâs volume control is better is probably purely personal preference. I use which ever is convenient and/or better matches my current preferences.
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Independent of what Ted may say above/below, I do not consider any DAC to âhave a Preampâ. DACs and Preamps are two different things. DACs are generally a line-level source. Admittedly the DS DACs are not like old-school DACs.
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My findings are that the DSJ into an integrated amplifier sounds great but I really needed to add an active preamp into the mix when I use the DSJ with my Pass Labs power amplifier. The addition of the preamp allows me, as per Tedâs advice, to run the DSJ at âhighâ gain which to my ears sounds a bit better than the âdefeatâ or âlow gainâ setting on the DSJ. It also addresses issues with gain in my system as my Pass Labs XA25 actually has low input sensitivity (compared to other PL and most other power amps out there).
I went through a similar process of trying and buying to others on this thread. I really liked what the W4S STP_SE did in my system but I eventually succumbed to a BHK Preamp as I loved what the tubes were doing to the sound. I tried passive and active preamps from a number of manufacturers and at different price points.
I agree. Youâll note that I didnât mention the DS having a preamp. It has a volume control, but no gain, no input select, etc. and itâs implemented with zero hardware.
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Thanks everyone for chiming in, and thanks @tedsmith for the clarifications. I apologize for hijacking the thread down this preamp conversation, but at least itâs something different to chew on until DSJâs Snowmass is released!
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They are few and far between but I have a PDX DAC which was designed by an Australian bloke not far from where I live. It has a tube pre output stage. LDR volume attenuation, 6922 tubes. Iâm about to mod mine by removing the upsampling chips (making it NOS) and then pulling the Hiface USB input board and replacing it with a JLSounds USB to I2S to feed the PCM1704K dac chips directly. Fun times.
âTheyâ are what, exactly? A DAC with a tube pre out stage is more than a traditional DAC, which is a line-level device. What you describe sounds like a preamp. Iâm fully willing to admit ignorance (not kidding), but Iâm still missing what the passive vs. active preamp thing is, on the subject of DACs. Iâve had passive and active speakers and so on.
The DS DACs are different (correct me here, Theodore, if I stray) with respect to this subject only in that one can attenuate the level from full Line output level (â100â) to levels below that without significant penalty. Traditionally, if you lower the output level of a DAC, youâre shedding Bits, which results in lower resolution.
This has, throughout my âdigitalâ life, been the problem with NOT RECORDING/DOING STUFF at full level*, is that you were coughing up resolution every step of the way below Full Level recording. Iâve heard various numbers, but recording with your peak level 6dB below the possible 0dB was similar to losing 2 bits of resolution - so, âback in the dayâ we were talking about getting effectively 14-bit res vs. 16 - which was not insignificant. Nowadays, with much higher bit and sample rates, it is not so dramatic.
- This is one of the things that led to most working audio people to always try and record Full Digital Level, and also subsequently led to compression/Loudness Wars, etc. It is a fundamental difference between analog recording and digital.
Bad, I deleted your email signature as it included personal information.
When you respond via email your email signature is posted to the forum as part of the message. There is a simple work around by adding something to your email signature which Paul told us about, but I do not recall what it is.
Not sure where the confusion is. I think we both agree on what a DAC is. A preamp can take many forms, both active and passive. Passive preamps can be either simple attenuators or line buffers - a buffer changes the input impedance to one that the source likes and the output impedance to one that the amplifier likes (First Watt make one, there are some nice transformer based line stage buffers as well). Then you get to active. Active can be with no gain (attenuation only like the W4S STP does except at the very top of its volume output where is doe add gain (confusing)). A conventional active preamp provides gain and attenuation where needed and sufficient voltage at a good output impedance to satisfy the requirements of a power amplifier. The DAC I am talking about is a DAC, with an active preamp section that has attenuation i.e. it has the correct voltage output, output impedance to properly drive a conventional power amplifier and it has an attenuator to alter the output voltage to provide a volume control to a power ampâ.
Thanks
Though admittedly, anyone on PPosts with a blue name is out thereâŠ
I was responding to this comment BTW.
Here is the trick. Modify your signature by placing a line just above it with "-- " (two dashes followed by a white-space character) on a line by itself
Followed you up to the last sentence. Not trying to be a pain, and will admit to impairment/brain fatigue at this point in the day.
A DAC with an active preamp section sounds like a preamp/DAC�
Gawdamighty, learn something new every day. Though I may have to simply delete the signature or use another minimalist signature.
Sure, Why wouldnât it?? Itâs both components in one chassis. If itâs done well then it saves space, cables and maybe expense.
Could you elaborate on:
âIf your system just happens to expect the output voltage range of the [DS]â
How can one tell if the system (amp) expects the output range of the DS?
It depends on the gain and sensitivity of your amp, the efficiency of your speakers, how loud you like to listen. The output voltage of the DS is 1.4VRMS, you can take the input sensitivity of your amp to see youâll need to turn down the DS to avoid overdriving your amp (pretty unlikely.) Then you can use the amps gain to see what 100 on the DS translates to as a amp output voltage. Then you can use V^2 / R (with R being the nominal impedance of your speakers) to get the power into the speaker, then you can take your speakerâs efficiency to see what the dB level is a meter from your speakers, then how loud do you like it?
Every stage of that calculation has approximations and potential for error. Itâs much easier and more reliable to just try it. I think most people would be well off to have a good preamp on hand, even if it turns out they donât need it for one particular system setup. Youâll probably need it sooner or later.
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What I meant was - that would appear to me to not be just a DAC. It is a DAC with a preamp stage, so that one might have less need for an external preamp. I wasnât meaning âsoundsâ in the audio sense. : )