It is usually done by transistors, but not necessarily: https://linearaudio.net/sites/linearaudio.net/files/ThevalveDAC_PCB_FPGA_files for web posting.zip
That makes sense when the DAC is based on single-bit techniques and the digital signal processing in the computer program is better than what is integrated on the DAC chip. Otherwise it's just an unnecessary complication.
In any case, as was said before on this thread, loudspeakers and room acoustics usually make by far the biggest difference.
That's the challenge of room acoustics. Making it look acceptable or doesn't look like there are acoustic treatments but works for the acoustic performance. Sky is the limit.
Don't waste your time / money on DAC which is already a matured technology.
I still would like to build a tube pre or something of quality that can give me an entry way into the "tube" sound to my system.
Since my dac has a volume control and I dont need additonal inputs or outputs on the pre. plus the input and output both need to be balanced would this help clean up the cirtcuit and allow me to build something of good quality?
What makes those 3k-5k tube preamps worth so much? Is there a way to source high quality tubes and capacitors and resistors and a good power supply and get the same sound quality for much less?
PS i am reading threads in this section to try to find something I can do along the lines of
12B4 based line stages.
PS. if I wanted to add a subwoofer into a 2 channel stereo pre what is the best way to do that without a dedicated sub out from the pre?
I am also building a IB subwoofer for my room. I would ilke the flexability of using a sub if needed.
So far I have read
1. use the speaker outs from the amp if you sub can accept a high speaker level input ( i cant)
2. use the rca outs from your pre instead
Would adding a active crossover in between a pre and a amp cause further sound coloration that should be avoided?
Since my dac has a volume control and I dont need additonal inputs or outputs on the pre. plus the input and output both need to be balanced would this help clean up the cirtcuit and allow me to build something of good quality?
What makes those 3k-5k tube preamps worth so much? Is there a way to source high quality tubes and capacitors and resistors and a good power supply and get the same sound quality for much less?
PS i am reading threads in this section to try to find something I can do along the lines of
12B4 based line stages.
PS. if I wanted to add a subwoofer into a 2 channel stereo pre what is the best way to do that without a dedicated sub out from the pre?
I am also building a IB subwoofer for my room. I would ilke the flexability of using a sub if needed.
So far I have read
1. use the speaker outs from the amp if you sub can accept a high speaker level input ( i cant)
2. use the rca outs from your pre instead
Would adding a active crossover in between a pre and a amp cause further sound coloration that should be avoided?
There is a lot to be said in favor of using speaker level I/Ps on subwoofers. You pick up some of the sonic signature of the main amp, for better blending. That could be quite important should you decided to switch from the SS Parasound unit to something that's tubed.
There's no reason why your DIY SW can't have speaker level I/Ps. "Plate" amps with the feature are commonplace. Look here and here.
There's no reason why your DIY SW can't have speaker level I/Ps. "Plate" amps with the feature are commonplace. Look here and here.
If your music library consists of lossless files and hi resolution rips of SACD then I'd put money into the best processor and clocking first. If you use lossy compressed files then you don't need an expensive DAC but you do need to calm down all that crappy MP3 compression. For crappy compressed MP3 the tube stage helps more than if you have lossless files. In my opinion, and I have over 300,000 tracks of lossless audio, I found simply running direct is best into a solid state amp. I also play same DAC into tube amps though. If I did have any compressed files I would probably consider a tube stage to hide all the crappy compression.
I agree wholheartedly running a sub from speaker outputs is best for music. For movies with surround decoding use the LFE output because the sub is part of all the surround decoding. But for straight up music listening I'll use the speaker outs in nto the subs crossover any day, sounds better.
In that case, I don't think there is an alternative to you personally spending time auditioning some tube preamps. Part of process in being an audiophile is the joirney of discovering just what it is the are searching for self-education which occurs simply from lostening. In my mind at least, zero loop feedback triode preamps tend to be more 'musical' than transistor preamps, especially those utilizing high feedback. That said, I'm not seeking to engage anyone about what is just my opinion.
A final bit of advice I'd like to offer you is to, trust your own ears about what sounds right. I've more than once regretted a purchase made on the advice or reviewers, or friends, or simply on brand reputation. Everytime, I ended up wishing that I had trusted my ears. At first, your personal listening judgments may prove less than perfect. Over time, however, you'll discover your judgment steadily improving. That's the audiophile journey.
Last edited:
i get it.. i spend some time listening last night and was having a blast. things sounded crisp and clean at low volumes.
Then all of a sudden it sounded lifeless. not sure why
do amps get tired lol?
I am thinking it might just be some badly recorded source material.
all my audio is lossless. but i do know some cd's were not recorded very well.
How do i get into the audition game? i wish i had more friends locally into this hobby? its hard to find dealers that will let you try stuff out anymore.
I have been sitting on the fence on upgrading "somethiing" for 5 years now. I keep talking myself out of it.
I decided on the DIY IB sub as it would give me something to do which would keep me engaged in the whole project. And its why I am looking at a tube pre.
I already purchased a pro amp to drive the sub drivers. Is there still a way to add a speaker level to line level device? plus a crossover?
Do you need to put in a high pass crossover for the main speakers? or just let them play full range and do a low pass crossover on the sub and eq it to compliment what the mains do?
Then all of a sudden it sounded lifeless. not sure why
do amps get tired lol?
I am thinking it might just be some badly recorded source material.
all my audio is lossless. but i do know some cd's were not recorded very well.
How do i get into the audition game? i wish i had more friends locally into this hobby? its hard to find dealers that will let you try stuff out anymore.
I have been sitting on the fence on upgrading "somethiing" for 5 years now. I keep talking myself out of it.
I decided on the DIY IB sub as it would give me something to do which would keep me engaged in the whole project. And its why I am looking at a tube pre.
I already purchased a pro amp to drive the sub drivers. Is there still a way to add a speaker level to line level device? plus a crossover?
Do you need to put in a high pass crossover for the main speakers? or just let them play full range and do a low pass crossover on the sub and eq it to compliment what the mains do?
Definitely let the main speakers play as close to full range, as they can. Configure the SW stuff to fill in "underneath".
Remember the impedances in parallel law. 1/Znet = 1/Z1 + 1/Z2 ... + 1/Zn
Placing a 10 Kohm pot. in parallel with the main speaker is "invisible", while providing control over the signal level driving the SW crossover. Just make sure that the I/P impedance of that crossover is >= 100 Kohms.
Are brand name preamps worth the cost? I asked on the polk forums and they threw out some brand names that are all pricey. Joule-VTL-VAC-Cary- Conrad Johnson- Minimax-Musical Fidelity
Is there some complexity to the design that they use that makes it better or are they just using quality components? + name
Are there no-name designers out there that sell kits that you can put together that can rival these fancy names?
Is there some complexity to the design that they use that makes it better or are they just using quality components? + name
Are there no-name designers out there that sell kits that you can put together that can rival these fancy names?
If you want (single ended) tube sound, get (single ended) tube amp.
$3k-5k is way too expensive for any preamp regardless of transistor or tube. Just get a solid state preamp with interface you need which shouldn't cost anywhere near 3k-5k.
I use active crossover for my stereo which includes SET tube amp and active subwoofer. It gives me the sound I want, thanks to the room acoustic treatments.
Not sure what you have but every powered sub made generally has many input choices, RCA, tos, speaker, etc. the low pass X over is in the sub, you just run a set of parallel wires off your main speakers into the sub. If your mains are small then run them full range. If your mains are big speakers that have strong extension below 60hz then you can still run them full range but you may have to move the sub around the room to see what sounds best and play with cross over frequency and sub level to get a good smooth blend at listening position.
If your mains have deep extension then lower the crossover freq knob on the sub to a lower cutoff than you would for small speakers. I have never run my subs over 90hz, even with bookshelf speakers. With big mains you may see that 50 or 60 hZ is good. Setting up subs is all ears and walking into corners and listening, there is no piece of test equipment available without putting DSP into your system like an AV receiver. For a pure analog sub, it's all trial and error. The advantage of using speaker in is that your system volume also controls the sub and as your mains roll off the sub is filling in at a gentle 6db per octave. It's a passive crossover in the sub.
Last edited:
I strongly agree with the sentiment that many brand name preamps are poor values. You pay too much for the name plate, fancy cosmetics, features that never get used, and "boutique" parts that frequently fail to add anything of consequence to the real net performance.
Windcrest77, if I correctly interpret the OP's remarks, he is not using a "plate" amp with his DIY SW. A "pro sound" power amp and separately sourced crossover stuff seem to be what has been selected.
Windcrest77, if I correctly interpret the OP's remarks, he is not using a "plate" amp with his DIY SW. A "pro sound" power amp and separately sourced crossover stuff seem to be what has been selected.
I see, I hate the idea of doing anything "high pass" that will only color the mains. He would just need to split some lows off of his speakers and use the level control on the new sub amp to control the level of the sub, but he probably won't have a frequency knob. A small low pass 6db per octave buffer at 80hz to feed the sub amp, the speakers would be connected, tapped, into this buffer. Now There is a valid use for a tube in this whole discussion. Simple one tube cathode follower passing only from 80hz down. With this setup once he sets the sub level proportion, changing the system volume and the sub will follow proportionally.
I am still waiting on my drivers but it will be driven by a regular pro stereo amp in parallel mode. I have already picked one of them up used along with a fbq2496 to add some equalization. I have a behringer 8000 mic and mic preamp and plan on doing some room measurements to equalze the sub once its built. I plan on playing with or considering room treatements at the time.
for what its worth the speakers i have are rated for 25hz to 27 khz at -3db. I would imagine they would be ok with no crossover. I just need to find a crossover for the sub or some sort of speaker level input. I think I should be able to equalize the subs for both HT and music seperately as the stereo speakers are seperate from the HT speakers.
As a side node I have a whole seperate 7.1 system in this room with a projector for HT. seperate amps and a receiver. which was the main purpose of this sub. adding it to the stereo setup would be a bonus.
Could you give me some decent but cheaper names of tube pre pre manufactures to look for? I see a lot of project websites that sell kits as well as fully assembled. However I dont want to throw money at some random stranger without knowing I am getting something quality. I also have seen some chinese made tube products.
for what its worth the speakers i have are rated for 25hz to 27 khz at -3db. I would imagine they would be ok with no crossover. I just need to find a crossover for the sub or some sort of speaker level input. I think I should be able to equalize the subs for both HT and music seperately as the stereo speakers are seperate from the HT speakers.
As a side node I have a whole seperate 7.1 system in this room with a projector for HT. seperate amps and a receiver. which was the main purpose of this sub. adding it to the stereo setup would be a bonus.
Could you give me some decent but cheaper names of tube pre pre manufactures to look for? I see a lot of project websites that sell kits as well as fully assembled. However I dont want to throw money at some random stranger without knowing I am getting something quality. I also have seen some chinese made tube products.
The benefit of subwoofer is to deal with room mode. Your main speaker location may work against low frequency response in the room which will nullify their low frequency output. In such case, you either relocate the mains or add a subwoofer to take over the low octaves at ideal location.
Yeah, give a rebirth to your full digital system with the fashion of the good ole tube 😱
Somebody mentioned snake oil?
i will be able to figure that out after measurments i hope. i might not even need a sub 🙂
are you suggesting I am wasting my time. that is exactly what i was trying to do. get a different effect in my all digital setup
- Status
- Not open for further replies.