This is a discussion thread for the Starving Student II, launched today. If you have any questions about the SSII, this is the place!
Links:
Links:
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This project looks fantastic! Thanks!!!
I'd like to understand a bit more about its specs. Could we know the amount of Gain? And maybe THD vs output? I read people saying its mostly H2 dominant, but is that accurate? What are the changes from the SSI (that has a bit of reviews out there and can serve as a starting point of conversation until this is out in the hands of others).
But the tech data does not always speak about the sound quality. So, to someone that has heard it (6L6 alone at this point? 🙂 ) or that can 'imagine' its sound based on the schematic:
How would this stand up agains something like the WHAMMY for instance (in terms of pure Headphone AMP or even as PRE)? Perhaps another useful comparison would be the KORG HA-KIT HEADPHONE AMP KIT also available at the store?
I know part of the charm is just building stuff and not always having the best sounding equipment, but there is a limit to what wives allow us to put in the house! 😉 😀
So I'm intrigued, as someone that has already built and love the WHAMMY, if this would provide either a significant upgrade or at least a significant lateral move to invest the time for this project and move it to the top of the list... or will it be a little less good overall and be more of a nice project to build rather than a 'better' final product.
And then there is the ultra-practical approach: for someone wanting to get a grip of how tubes sound, how would this new project compare with market options like the Schiit Vali, which I almost bought just to get an idea of tube sound.
Any feedback, either technical or leaning to the subjective side with some measure of objectivity would be very much appreciated.
Thanks a lot,
Rafa.
I'd like to understand a bit more about its specs. Could we know the amount of Gain? And maybe THD vs output? I read people saying its mostly H2 dominant, but is that accurate? What are the changes from the SSI (that has a bit of reviews out there and can serve as a starting point of conversation until this is out in the hands of others).
But the tech data does not always speak about the sound quality. So, to someone that has heard it (6L6 alone at this point? 🙂 ) or that can 'imagine' its sound based on the schematic:
How would this stand up agains something like the WHAMMY for instance (in terms of pure Headphone AMP or even as PRE)? Perhaps another useful comparison would be the KORG HA-KIT HEADPHONE AMP KIT also available at the store?
I know part of the charm is just building stuff and not always having the best sounding equipment, but there is a limit to what wives allow us to put in the house! 😉 😀
So I'm intrigued, as someone that has already built and love the WHAMMY, if this would provide either a significant upgrade or at least a significant lateral move to invest the time for this project and move it to the top of the list... or will it be a little less good overall and be more of a nice project to build rather than a 'better' final product.
And then there is the ultra-practical approach: for someone wanting to get a grip of how tubes sound, how would this new project compare with market options like the Schiit Vali, which I almost bought just to get an idea of tube sound.
Any feedback, either technical or leaning to the subjective side with some measure of objectivity would be very much appreciated.
Thanks a lot,
Rafa.
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About the specs...
I'll run some measurements this weekend and post them.
This is very similar to the original Starving Student. It still uses a power MOSFET source follower, which is loaded by the tube heater, and a triode voltage amplification stage.
The main difference is that it uses a different tube (19J6's have become unobtainium), and also the addition of an optional CCS plate load. There's a jumper that lets you select the CCS or a resistor. This changes the sound quite a bit - with the resistor, clipping is softer, and 2nd order distortion is higher. Personally I think this best fits efficient headphones (or preamp use). The CCS raises the gain and lowers the distortion, and the amp can put out more voltage before clipping - but clipping onset is more immediate.
I also added a muting relay to get rid of any "thump" that you get when powering on and off.
Pete
I'll run some measurements this weekend and post them.
This is very similar to the original Starving Student. It still uses a power MOSFET source follower, which is loaded by the tube heater, and a triode voltage amplification stage.
The main difference is that it uses a different tube (19J6's have become unobtainium), and also the addition of an optional CCS plate load. There's a jumper that lets you select the CCS or a resistor. This changes the sound quite a bit - with the resistor, clipping is softer, and 2nd order distortion is higher. Personally I think this best fits efficient headphones (or preamp use). The CCS raises the gain and lowers the distortion, and the amp can put out more voltage before clipping - but clipping onset is more immediate.
I also added a muting relay to get rid of any "thump" that you get when powering on and off.
Pete
I can see that there are some specs now at DiyAudio Store for 30 and 150 ohm load. I have ordered a kit and will probably use the amp most as a pre-amp so behavior in an eg. 10k load is also interesting.
Building this weekend!
Received my parts kit yesterday, really quick processing and delivery! Thanks diyAudio Store. Will get started on it today!😀
Received my parts kit yesterday, really quick processing and delivery! Thanks diyAudio Store. Will get started on it today!😀
Thanks for the info. Indeed, there are now interesting specs, and I... as Meeper, was wondering what the 10K figures would look like.
Great seeing folks already getting their kits, please let us know how they turn out!
So Pete, you would suggest to use the Resistor plate load if it suffices, and only go CSS if you need more gain? What about 300ohm Sennheizer HD600? Where would this fall regarding plate?
Thanks!
Rafa.
Great seeing folks already getting their kits, please let us know how they turn out!
So Pete, you would suggest to use the Resistor plate load if it suffices, and only go CSS if you need more gain? What about 300ohm Sennheizer HD600? Where would this fall regarding plate?
Thanks!
Rafa.
After more than 50 years of DIY audio, and upon receipt of the invitation email to purchase the SSII kit, I realized that it is most likely now-or-never to dip my aged toe into the 'sea' of tubes. I purchased the full kit!
I'll be using the SSII with my Hifiman HE400S headphones (22 ohm impedance, 98dB sensitivity).
So questions (in ignorance):
1. How long are the tubes expected to last?
2. Will different tube brands sound different?
3. Would there be any benefit to channel matching to have a matched pair of tubes?
4. Will the tube model become 'unobtanium' like the original SSI tube model has become? That is, should one 'stock up' on a favored tube brand?
5. Would there be any benefit to increasing the size power supply input reservoir capacitor? If so, how much?
Thanks,
John
I'll be using the SSII with my Hifiman HE400S headphones (22 ohm impedance, 98dB sensitivity).
So questions (in ignorance):
1. How long are the tubes expected to last?
2. Will different tube brands sound different?
3. Would there be any benefit to channel matching to have a matched pair of tubes?
4. Will the tube model become 'unobtanium' like the original SSI tube model has become? That is, should one 'stock up' on a favored tube brand?
5. Would there be any benefit to increasing the size power supply input reservoir capacitor? If so, how much?
Thanks,
John
My package arrived today and it went together quickly. It really sounds great. Used it as a HPA and a pre-amp . Both times it was impressive. Thanks to the store for a great kit.
Terry
Terry
The install instructions call for R13 and R21 to be 1.4 watts.
Is this correct?
In the photos they look the same as all the 1/4 watt resistors.
Thanks DT
Is this correct?
In the photos they look the same as all the 1/4 watt resistors.
Thanks DT
Just a 'typo'. It should read 1/4 watt.
If you scroll down to the Appendix 1, R13 and R21 are correctly listed as 1/4 watt types there.
Shared album - Patricio Ri - Google Photos
Got it in the morning, completed in the afternoon. I do not use headphones that much, I paired to "The DCPP engineer's Amp" as a Pre. I does sound really good, it gives a very organic sound. I'm using the CCS load option, I'll probably try the resistive load later.
My gratitude to Pete Millett and the DIYAudio store for providing this kit, it was easy to build and, again, it sounds great.
Got it in the morning, completed in the afternoon. I do not use headphones that much, I paired to "The DCPP engineer's Amp" as a Pre. I does sound really good, it gives a very organic sound. I'm using the CCS load option, I'll probably try the resistive load later.
My gratitude to Pete Millett and the DIYAudio store for providing this kit, it was easy to build and, again, it sounds great.
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Hello,
Quick question for you guys.
Does this unit used as a preamp put out enough to drive the Amp Camp amp well? I know not all preamps seem to do so and am asking if anyone has tried this one.
Regards,
Greg
Quick question for you guys.
Does this unit used as a preamp put out enough to drive the Amp Camp amp well? I know not all preamps seem to do so and am asking if anyone has tried this one.
Regards,
Greg
Completed my build this morn - 1st tried it out with some HD650 phones - more than adequate drive, very nice sound. Curiosity then arose, so I swapped it in for a BottleHead Smash preamp & drove an ACA - plenty of drive & combo worked very well. I'll have to do more careful listening when I get a chance to see if all the subtleties that the Smash did so well are still present. I'm using the CCS option - when I did the first test (outside of the case, I noticed a bit of static noise at high volume settings with the resistor option (and less gain).
The build went well & quickly - some of the solder pads are quite small, so it took a bit more care to get them right (especially if they led to the ground plane, lots to heat).
I've got a Whammy kit waiting to be assembled (I put it off, since I wasn't looking forward to chassis work) - when I get that together, I'll try to compare.
Rich
Well... as usual, those that prefer to think it over and those undecided DIYers please refrain from purchasing in the store! 🙂
Congrats on selling out on the first 5 days of availability and only couple of days after the email invite. Incredible community! Looking forward to the builder's opinions (hope they mostly went to actual builders and not hoarders that would later on resell them on eBay at a profit 🙁 🙁 🙁 )
Best regards,
Rafa.
Congrats on selling out on the first 5 days of availability and only couple of days after the email invite. Incredible community! Looking forward to the builder's opinions (hope they mostly went to actual builders and not hoarders that would later on resell them on eBay at a profit 🙁 🙁 🙁 )
Best regards,
Rafa.
10k load won't be a lot different than 150 ohms. You can see at 30 ohms the output is current limited - the follower cannot deliver more than ~100mA.
300 ohm Sennheisers could be good either way, but if you listen very loud you probably want to use the CCS plate load. Best to try both and see which you like best...
Pete
That was pointed out to me by 6L6... on the next batch I made the pads bigger. Sorry about that!
Pete
1. Should be the same as any small signal tube... I would expect 5-10,000 hours.
2. There may be subtle differences from one type of tube to another. I would not expect anything drastic.
3. I doubt that any difference would be audible. Of the units I've tested the gain was matched to about +/-0.2dB.
4. The risk with any project that uses an unusual tube - it's possible that somebody will buy up the world supply. I've learned that lesson. There are quite a few out there (they were used in the last generation of the "all american 5" tube radio), and I proactively bought a lot of them (thousands). So hopefully this won't be a problem. If they disappear, there are other tubes that can be used with a resistor change.
5.. I think there would be no benefit.
Pete