This is a preamp for us DIYers offered from the mastermind of the PassLabs preamps - Wayne Colburn.
It sounds very detailed combined with a clarity and without harshness. Bass is solid and controlled. I used
TOSHIBA TTA/TTC004B for the outputstage. Drives all my Poweramps (F-5T, BA-3, BA-1, M2X, 50W-SE-Schade)with ease.
Absolutely no noise audible in my combinations. Can also drive headphones (with big BJTs in the outputstage).
PCB is of excellent quality and was delivered very fast. Thanks to the DIYAUDIOSTORE-team!
Build it - enjoy it!
I wanted a high-quality HPA and didn’t wish to pay over-the-odds for sub-par consumer designs. As it was designed by a pro from a proper hi-fi company, I saw it as a bit of a no-brainer decision. The build took me about six days to complete with cutting chassis etc and making a few mistakes along the way. As it was my first time I wanted everything to be correct and my fussiness paid off this time - On Power up all was perfect and I was pleasantly surprised. Would definitely recommend this build to those who appreciate real hifi and music-lovers who don’t want to break the bank. I am a music-lover not an Audiophool.
been looking for a linestage that fits my M25 (Babelfish) better than BA3FE or other chippy preamps i tried.
this is it! clear sound - not mumpfy, not sharp.
till now i've just made the standard model running on 20VDC. no bigger semis in Q8/10 position.
still looking for a nice housing.
Thank you Wayne!
I built a pair of mofos and these are a joy to listen to. Often I listen to music and think that’s glaring or harsh or not revealing, but not with these. No, instead I am smiling, drawn into the music and pleasantly surprised by what I am hearing. Oh, and it is so simple and doable. So I bought two more sets of boards to build a double mofo. That’s going to be more work, and I am sure it will take me months to complete. I am mofo crazy now.
As many folks during COVID-19 lockdown, I was looking for projects and this one fitted the bill nicely--even though I wasn't in need of another headphone amp. The kit is very relaxing to build, even without the well-written and well-ilustrated instructions. Basically, the markings on the PCB provide sufficient information for putting it all together. Even though I have considerable experience with electronics, I would say that with patience and care, this kit could be assembled successfully by a complete beginner. I took my time to do it over two evenings, going from lowest height (diodes), to resistors, to highest parts (heatsinks). For those, my vintage 1985 Weller gun came in handy. The only little gripe is that in my opinion the headphone jack should be soldered AFTER the whole thing is assembled, as soldering it with the plastic in contact with the PCB resulted in my case in a slight vertical misalignment with respect to the front panel hole. The switch and volume knob were perfectly aligned however, so it's definitely a phone jack issue. I decided to solder the current source LED on the component side of the PCB. I might be old-fashioned, but tubes usually don't glow blue... At such low heater current, these don't glow much anyway.
I feed it from the Tape Out of a Rotel RC-995 preamp via 25' of RCA interconnect (yes!) and the sound is sweet. So far I have only used the constant current source mode. The tubes are very microphonic, but since the heater current is very low and the tubes remain cool, any tube damper would likely fix this. I haven't bothered with that yet, since the amp is on a small IKEA bed table and I don't touch it. I have used it with Grado SR225e, B&O H6, Audio Technica ATH-M50x and... a pair of Koss Porta Pro. Great kit that is easy to assemble, sounds very good and looks completely professional. Makes a perfect gift--assembled or not!
A very nice design. Enjoyed the build, was straight forward and not too pricey of a BOM. Excellent sound. Going to play around with a couple different OpAmp (almost like tube rolling).
This is my review of Pesante 5U the first thing that impresses me is the paint quality is excellent, metal is heavy and I love that the only thing that got me to confuse is the screws they are similar types and I didn't know which goes to what, it will help if on the instruction there is a small section with at least shows where those screws go by the way packing is excellent well-padded this build you see here have two 300 mm long heat sink and they look small on the case so that gives you an idea of how big is this chassis other than that I'm really pleased and happy with this chassis
I bought the kit toward the end of summer 2019, built it during the fall. Building the amp was great fun. The instructions were easy to follow. Sounds great with an inexpensive passive preamp (Bellari) and a PAS-3 as my phono preamp. My only reservation is power consumption. I was surprised to see it drawing 90 watts for just 8 watts/channel of output. I suppose that's the nature of Class-A design. And 90 watts is much better than the 190 my old amp was using.
I bought the both the PCB and parts from DIYaudiostore, and soldered all the parts during two evenings. The instructions were easy to follow. I acquired a suitable aluminium enclosure, which required some metalworking (drilling holes and making threads). The amplifier is driving my 600 Ohm Beyerdynamic headphones with ease. Very satisfied with the sound, and it was fun to build!
Totally fun build. Great guide—in true DIY spirit. I listen to Noir daily during desk duty. Also have 2 Whammy's by comparison. Noir is its own gem. Pick some phones—pick some flavors—I'm an HPA fanatic and love them all. I interviewed several pairs of headphones—Beyer 1990 pro are a great match for Noir—to me—and my ears. Massdrop Focal Elex are awesome too! Oh and switching jack????? Makes a solid preamp too!
PCB quality is top notch. Mark is a bada$$. Get the with chassis version—it's unique.
Love this preamp—I was lucky enough to get a pre release to build (my images are NOT of the final PCB). Clean, clear and detailed—with Aleph J—nice combo I think. Headphones out with a switching jack—YES—and it's great! Check the thread on the DIYAudio forum for build ideas. There's some good info. BUILD THIS PREAMP!
Very high quality JFET. They were set to run class A in the F6 amplifier, run very hot but without heat sink. I nearly run all day, every day in the Summertime, they still alive. Now, for saved money, I added a small fans for them. Excellent sounding, no noise can be heard at all. Thank you very much.
I enjoyed building this kit, and will continue to use this amp in my system. Unlike some audiophiles, I tend to roll amps for different character, or to test a new set of speakers that I have built. To do again, I might change the layout that I used for the power supply and circuit boards, and added an input sensitivity selector, but that's about it. The bass is great as I expected, and yes the rest of spectrum is fine for me.
I used the power supply and it is a beefy linear type. A 3 amp fuse is ok to use, but I think that I might recommend a slow blow type.
The documentation for the soft-start board is a bit stale, but generally adequate. The PCB quality is first rate, and the overall design is good as well. I substituted an Omron GSLE-1A4 (24Vdc) relay because the specified part was no longer available. It fits and works well. This relay has a 10 amp rating @ 250Vac. I used a 1.0 uF MKT X2 rated capacitor for the input power supply. Smaller capacitors I experimented with, did not seem to supply adequate current. I wanted a long delay, so I up-sized the timing capacitor to 4700 uF, which gave me about 2.6 seconds delay to relay closure.
Wayne's design of the headamp is simple but excellent and so is the parts kit provided by diyaudiostore. Only high-quality-parts. Fast shipping. I only changed two parts: the headphone-jack (I used a Neutrik which is isolated from the Chassis) and the opamp (the red part, it's the burson V6 vivid). Chassis is Hammond. It perfectly fits the PCB.
Al in all an outstanding headamp.
This is a great place to start for diy audio!
It was my first PCB soldering attempt, and i did struggle a little bit at first, but the clear instructions and easy layout and labeling helped me through. I did struggle a bit with some of the larger joints with my 25W Weller (especially the heat sinks), but overall very straightforward.
Also I decided to put the LEDs all on the bottom of the board, as long as you pay attention to orientation and shift the order you attach the parts a bit (do the second set of LEDs before the sockets) I haven't had any issues.
Great Quality Board. easy to get parts from Digikey. everything fit perfectly.
Hello I have bought them to build the "Boozhound Laboratories Deluxe JFET Phono Preamp". I have just soldered them, check the DC biasing and it was everything perfect according to spec. NO troubles. Sound is great and clean. Noise is very low.
It was a good service.
The chassis was very well built, particularly for the price and worked well for my purpose. I ordered the 10mm front panel and it gives the amp a very finished look.
What a wonderful sounding preamp. Build took me about 4 hours as someone with moderate experience with electronics and a soldering iron. This is now sitting in front of Aleph-J and I'm in love with the sound. Microphonics were a problem but not hard to tame following others recommendations. Now just to finish my new DIY speakers......
I couldn't get over how EVERYTHING was in this kit. All quality parts. These guys know what they are doing trust me, cause I surely don't. I've never built anything electronic in my life. I'm the definition of beginner and I finished this amp in 3 days! It sounds amazing. Worth more than the price. I highly recommend this kit.
I ordered the LSJ74/LSK170 matched octet and I am happy with how my B24 amp sounds. Despite the long delays on the stock, there was some hiccups with the delivery to South Africa but once that was sorted out it didn’t take more than 3 days until the order was in my hands. I am happy.
Kit arrived very well packaged . With help from the build thread it was a straight forward build. I placed a piece of carpet underlay felt under the Nutube and the silicone ear pieces from earbuds on each mounting post. It is hooked to a M2x and sounds very nice.