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Kent I. says:

The kit is really pretty easy.  The instructions are clear and the photos help quite a bit. Bruce's kit is the first I've encountered with components packaged by board or assembly.  Nice touch!
I have quite a bit of experience building various audio kits. I say this as a point of reference -- The GG is a cakewalk. A very simple design with Bruce's clear instructions let me finish the kit with such confidence that I went ahead and installed the cover, installed the knobs and wiped down the fingerprints on the case before I turned it on for the first time. No problems at all. Dead quiet at full volume.
I don't think I can eloquently describe the sonic character with typical superlatives about sound staging and lack of brittleness, etc. All I know is that I have a HUGE grin on my face every time is put on disc. It is true that I have been surprised by additional detail exposed on some favorite discs of which I have heard literally hundreds of times over the years. But overall, just a natural rightness that defies my ability to describe. Perhaps that says the most... Heck, you're not supposed to hear your equipment. You're supposed to hear your music. Call me a very happy camper.

Larry W. says:

 The kit arrived today and I built it this afternoon. Start to finish, six hours, including gathering tools, reading the instructions cover-to-cover and setting up a temporary bench (cutting board on a chair, NYC apartment) and checking what I'd done with a digital multimeter. The LED came on when I powered it up and it didn't smoke, so
I kicked my ARC SP-4 off the rack and hooked it up. Wow!  I'm not totally inexperienced in solder slinging, but I haven't built a complete component in about 40 years. I have to compliment you on the superb instructions (I used to write service manuals) and the great PC board layout and execution. It was a dream to build and at no time did I experience the slightest frustration.  I've only had it powered up for about an hour, but I'm really impressed. It's getting better by the minute, and far outclasses the ARC (which was re-capped) and an Audible Illusions which went up in smoke.  I'm driving a Golden Tube Audio 300B SE into Hammer Dynamics Super 12's. I've got "Audio Reality" on order from your web site in order to explore your OTL amps and phono stage (currently a Lehman Black Cube). I'm looking forward to info on your new phono stage (MC + MM,  please!).
Once again, thanks for a great design, a great experience and stupendous sound.
 

Philip F. says:

OK, it's done.
After about 5 hours of work (I wasn't rushing), my grounded grid preamp is singing.
The instructions were faultless, the photos perfect. There were no extra and confusing details and no unclear instructions at all.
I have built kits by Dynaco, Harman Kardon, Assemblage and Velleman. This one ranks right up there with Dynaco (ie. the top) in terms of ease and speed of completion. No doubt this is largely attributable to the simplicity and low part count of the circuit, but who cares? It was just so nice to finish a kit with no ambiguous part names, no perilously placed parts, or awkward or badly sequenced operations. Lots of space, no clutter.
I have just hooked it up downstairs to an old home brew Quantum SS amplifier, my discman and some cheap paradigm speakers. Even with this level of associated equipment, there seems to be something very special about the sound... but more on that another time. In the first flush of completion, everything sounds good, if not fabulous.
The grounded grid provides gain, but no apparent loss of transparency, no identifiable coloration, no added irritation, and no reduction of spatial illusion compared to the passive stage. There may be a slight apparent increase in detail ... I'm not sure why.
I don't feel inclined to try to compare the preamps directly (I'm not an audio mag writer) but I might one day.
Bravo, kudos, and felicitations, Bruce! I hope the kit is a big success.

Mike N says:

After a week delay (out of town) I've finished too. My first project ever, literally, plugged it in, checked output for DC, no hum, cool. Hooked it up in my room with the mono block OTLs (still had a slight disturbance when the caps charged, but just a quick hum) and all is quiet. Unfortunately, I can't use the relatively good DAC (Proceed AVP) and am using the Denon DVD5000 DAC. Oh well, yet another upgrade possibility.
Even so, closer presence, clearer "images", more relaxed presentation than with the AVP doing the pre work.
For the kit, if I can do it this easily, then be sure that Bruce has once again done a great job.

Bill B. says:
I too, assembled a grounded grid kit in five hours. I have had a Curcio Daniel preamp I built in 1985, a Conrad Johnson PV10 and an Audio Research LS7. I thought these were good preamps but they certainly are not in the same league as the grid. The grid is something else altogether. It is the most magical and clear preamp I have ever heard! This unit is astounding. I thought my stereo sounded pretty good before but there still was some roughness and a lack of absolute clarity but the grid just cleared everything up. I am ecstatic with this preamp and that has never happened before on anything connected to stereo.
I could rant for hours but I am going to end right here.

Jose G. from Spain says:
This Sunday I finished the Grounded Grid kit. I have to tell that I am a complete beginner, and that I had to learn to solder for this project (there are some nice links in the internet, and then I bought a $4 Velleman kit to practice). In addition, I am the kind of guy with "2 left hands". I have never put a frame on the wall. I think you get the picture.

As you can imagine, I was quite worried by the fear of not being able to finish it by myself, or getting it ruined, or do it to a substandard level.

Well, I was surprised of how easy it was. I could do it without any problem. The design was excellent, simple, well laid out, you do not need to have small hands or good view. Everything went flawlessly, and I ended it at 00:30 of Monday. I decided not to test voltages then, since it was very late, and I closed and screwed the lid, so as not to lose any screw. I would have time next week end, in the next DIY time. (I travel most of the week, except Mondays)

On Monday, I said "what the heck", and decided to connect it to the rig, untested. I did not have good additional interconnects, only the ones that came with an old Aiwa tape deck. You can imagine how they were. (Until then, I was running direct from CD player to amp, and I had one good set, but not a second) I really did not expect to work, but it did at first time.

And the sound! In my rig (Ah! Tjoeb 99 CD player, Decware Zen, Gallos Nucleus) it increased the weight and low and highs extension _from the very start, and then improved upon it with time. The only minor drawback was a shortening of the soundstage depth (which is huge with the Zen), but then I think the preamp has to break in for a while (at least 5-10 hours), and I'll have to change the interconnects to something decent (not expensive, but decent).

The reason for me to do this project was twofold: to get more inputs (for tape and phono) with the best performance available, and to prepare the path to get more power with the OTLs. The Zen, while being very good, puts out something like 2 Watts RMS, and that's barely enough..

If somebody wants to get a high-end preamp, get the satisfaction of assembling it himself and get confidence to get into the OTLs, this is the path!

Thank you , Bruce, for my sheer enjoyment.

Edward S. Says

I just got the GG kit today from Bruce, and I finished the kit in a total of 5 hours, this was my first DIY experience and I have to say what a great kit. The instructions are awesome as are the pictures included, I would highly recommend that you go the kit route it saves so much time and the results are very professional. The sound is most importantly fantastic, the preamp is dead quite and I hooked it up to an old B&K 212 solid state amp to test the results, amazing, I had a Belles preamp (not a bad solid state pre from the guy who makes the hotrod 150 amp) which it proceeded to blow away. All I can say is thanks Bruce, I am jacked about tackling one of the amps next.

David K. Says

I finished building the Grounded Grid preamp kit a week ago. The kit was extremely well thought out and constructed. The instructions were well written and illustrated with color photographs. In addition, Bruce takes the trouble of packaging each group of components that go together for a particular step in the assembly process into its own plastic bag, so that you have a much easier time locating all of the correct components in the right assembly order. I enjoyed the building process, and I wish everything that comes with the phrase "some assembly required" was as well designed, thought out and packaged.

The preamp worked fine from first turn on. After a break in period of a day or so, I started doing some critical listening. It blows my old Apt Holman preamp away, and the Apt is still a fine preamp in my book. The high end and mid range are more detailed, but the sound is not harsh or fatiguing. In addition, there is much more bass response, and that bass is well focused and not mushy in the least. Imaging and soundstage are both improved noticeably. In short, it sounds great, giving me the strong impression that I am in the same room with the musicians. The only modifications I have made are to add a tape input and tape output and to swap out the stock LED for a blue super bright LED.

I congratulate Bruce on an excellently designed and executed product. This positive experience has left me intrigued about the possibility of building the OTL amps some time in the future.