Passinwind

<p>[quote name='Chienmortbb' timestamp='1426691035' post='2720856'] I have enough space to do the pot/switch on either panel and the Decals are so thin that I can add the graphics to the rear later.[/quote] Being able to do the graphics in stages is a great reason to go with your method. I've done inkjet printing on sticky-backed plastic sheets a few times, but those decals look a lot nicer.

[quote name='Chienmortbb' timestamp='1426688085' post='2720796'] The graphics on the panel were designed on a computer and printed onto Waterslide Decal Paper. This works like the decals in an Airfix or Revell kit. [/quote] Looking really good. Are you going to have an EFX return pot and/or EFX bypass switch on the front panel?

[quote name='Bottle' timestamp='1426112296' post='2714668'] Oh, that's mighty purty [/quote] Thanks. It actually sounds pretty nice too, always a bit of a crapshoot when doing my own design. Here's the matching power amp: 700 watts @ 4 ohms, 7.5 pounds. The two modules will be able to fit side by side in a 19" rack once the new front panels get done, or can be stacked vertically for use with smaller cabs.

[quote name='JapanAxe' timestamp='1426078565' post='2714092'] Hmmm... The Trinity Trip Top chassis-only kit is $1600. [/quote] Huh? The link I posted says $670, plus $30 for a 50 HZ transformer core for those who might prefer that. Yes, there is a 234 volt primary. Is that link duff though?

[quote name='pfretrock' timestamp='1425772875' post='2710633'] Maybe get Barry onto the case.... [/quote] Yes, exactly.

Pardon me if I'm stretching the definition of effects a little bit. This is an in-progress pic of my current bass preamp/DI build: I'm just about to order the permanent front panel, which will look a lot like this, in blue anodized aluminium: There's a TalkBass build thread [url="http://www.talkbass.com/threads/a-diy-1-2-rack-bass-preamp.1135423/#post-16982343"]here[/url] as well, but I would be perfectly happy to discuss details in this thread if desired.

[quote name='pfretrock' timestamp='1425749990' post='2710364'] A bit expensive? Kit Price does not include tubes. Perhaps there is extra mojo in the transformers [/quote] [i]Buy once, cry once.[/i] But that high ticket was partially why I suggested pitching the general idea to someone more local to you guys, and maybe more in tune with the market there.

Here's a promising looking one based on the B-15: http://www.trinityamps.com/Product_Kits_Triptop.htm Maybe you can get your guy interested in doing something similar?

[quote name='Roland Rock' timestamp='1421918465' post='2666479'] Any detail on the power section? [/quote] A magazine reviewer I know mentioned that it uses one of the new ICEpower 700 series modules, which are reputedly a nice step up from the earlier versions. Edit: I now have a little experience with that module myself, it's a ripper.

[quote name='paul_5' timestamp='1425414549' post='2707143'] actually, if you were going to get inside it to mess about with the components then the most sensible suggestion would be to rip the 'Flash Burn' LED out and replace it with a sensible one... [/quote] That has worked well for me. I found some really nice low intensity diffused lens blue LEDs on eBay -- took a while to find them, but they do exist. I then run them well under the max current spec, and at that point they're no longer obnoxious at all, at least by my standards.

[quote name='jensenmann' timestamp='1425212546' post='2705058'] Thanks for the LT1169 info. I´ll give it a try. Some parameters do look promising. [/quote] It's a pretty nice sounding DIP-8 chip, LT1113 is decent too. Not the fastest or latest-greatest, but sometimes that can be a good thing.

[quote name='jensenmann' timestamp='1425153375' post='2704614'] . I´d say +1 to passinwind´s comments about TL072s and OPA2134s from that point of view. But in my experience with MI gear I´d propose to use TL072s because their artefacts make a certain sound which might help a signal to cut through on stage. HiFi sounds are not the easiest to handle thing for me on stage. [/quote] The Fender tone stack can get a bit lost due to all that inherent mid-scoop, for sure. I built up Rod Elliot's Project 27, which is a lot like how you've described yours. You might give the LT1169 a try if OPA 2134/2132 is too "gooey" for your taste, but you still want lower noise than the TL072 affords. I used Rod's bright switch circuit in mine, which cuts like crazy if desired. The Keutzer preamp's tone stack is a pretty standard Baxandall variant, which can be pretty hi-fi, but can also boost mids pretty effectively. In my own designs I sometimes like to mix the two, with active bass and mids in one section and a lossy passive treble control in another, later stage. All of this stuff depends a lot on playing context. I don't play fretted bass, ever, and rarely play much rock these days either. DIY builds can be great for really nailing things down for your own wants and needs, if you don't go crazy first!

[quote name='UglyDog' timestamp='1424794760' post='2700544'] Oh bum, I missed that Feel a bit of a twit for starting this thread now! That ½ rack pre of yours is gorgeous. [/quote] Thank you! Mr. Kreuzer passed away a few years ago, so I wonder if anyone is doing anything with the board layout he published, or has done an updated one? I'll look into that a bit.

I've not built one, but it looks pretty worthwhile and people I trust have told me it sounds good. Someone else posted about this last month: http://basschat.co.uk/topic/252766-kreuzer-bass-preamp/ Please keep us posted on how it goes. I always enjoy seeing how other people manage their DIY builds, and I'm just finishing up a [url="http://www.talkbass.com/threads/a-diy-1-2-rack-bass-preamp.1135423/"]new one of my own design[/url] at the moment, FWIW.

Stambaugh fretless: I've played it, sounds great.

[quote name='timmo' timestamp='1424528960' post='2697358'] I was just looking at the amps and cabs for sale and saw this. Just didn`t get what the function is, as i thought you would have an amp for all the functions. [url="http://basschat.co.uk/topic/253503-rare-gt-groove-tubes-bass-preamp-swr/"]http://basschat.co.u...ass-preamp-swr/[/url] [/quote] Quite a few of us use pro sound grade power amps in our bass rigs, for one reason because virtually no bass amps make enough power to satisfy some people. Since that power amp doesn't have tone controls and since it typically wants a higher level input signal than our basses provide, a standalone preamp like that becomes necessary. The often large-ish form factor also leaves lots of room for extended functions that are less often seen in integrated bass amps. Floor pedals tend to just provide another tonal flavor, and they can be very handy for getting "your sound" through someone else's rig as well.

[quote name='Chienmortbb' timestamp='1423657235' post='2687466'] So now to order some good parts and check out the latest circuit. [/quote] I just did a bit of benchmark testing in RMAA and saw a few subtle things that may need massaging, but it looks pretty good all in all. These figures are with both the high pass and the parametric EQ engaged, neither of which change the measurements all that much when bypassed.

[quote name='Passinwind' timestamp='1422986178' post='2679196'] Lookin' good, real progress going on. I'm on to final wiring of my set of preamp boards, hope to be up and running by week's end.[/quote] Done, and working pretty well for such early days. Should be safe to stuff those boards now Chienmort.

[quote name='lee650' timestamp='1423354769' post='2683959'] . I had a radial bassbone which dones not have high impedance inputs and it does not drove a power amp very well ( I struggled with my Berg IP, with the bassbone). [/quote] The new Bassbones do have a dedicated 10Meg piezo preamp now, but they are still unity gain pieces and as such are not meant to drive power amps.

[quote name='LukeFRC' timestamp='1421611251' post='2663295'] this is quite interesting thread [url="http://www.talkbass.com/threads/tb11-preamp-project.669517/"]http://www.talkbass....project.669517/[/url] [/quote] Yep, and there's also this one: [url="http://www.talkbass.com/threads/pcbs-for-diy-clone-2-band-preamps.737117/"]http://www.talkbass....preamps.737117/[/url] I built one of those Uncle Fluffy 2-band boards up, did a few of the documented mods, and enjoyed it a lot in my old Travis Bean fretless. This week I just finished up my own version, with a more modern opamp and film caps instead of tantalums. Seems pretty good so far, haven't tried a gig with it just yet though. There is a guy on Talkbass selling bare MM 3-band clone boards ATM, I think: [url="http://www.talkbass.com/threads/diy-stingray-3eq-preamp.883257/#post-12648941"]http://www.talkbass..../#post-12648941[/url]

Lookin' good, real progress going on. I'm on to final wiring of my set of preamp boards, hope to be up and running by week's end. I got diverted by a quick onboard preamp build for my ancient Travis Bean, similar to the MM clone one I sent you last year.

[quote name='pantherairsoft' timestamp='1422299313' post='2670909'] It certainly doesn't look modern, but it does look like it was built to last. We know Berg make stunning DSP for power amps due to the mind blowingly good powered cabs they have out there, so I have high hopes for how this will perform. Looking forward to giving one a whirl. [/quote] I'm really looking forward to checking it out too. The IP series inspired me to roll my own amp with the same OEM power amp/DSP chip set that Jim used. For his sake, hope he used something a lot more user-friendly on the programming end this time!

Here's a fairly thorough explanation from one of Peavey's amp engineers: http://www.talkbass.com/threads/class-d-illustrated-lots-of-pics.1083366/

[quote name='LukeFRC' timestamp='1421537771' post='2662590'] what's the hard bit? what makes it steep?[/quote] Many of the freeware layout programs have pretty arcane and/or limited component library formats, so I find that I spend a lot of time building my own component footprints. Things like ground plane layouts often still feel like black art to me too. And even for someone like me who has always been pretty used to winging things and "fixing it in the mix" later (rework and mods), I've found little mistakes on almost every original revision board I've done so far. I do find putting in the effort very worthwhile though.

[quote name='BigGuyAtTheBack' timestamp='1421489084' post='2661783'] Hi Charlie, I'm going to Veroboard it as I don't have the facillities to make PCB's. The last time I made PCB's was back in the early 80's when I was an electronics tech. The 741 was king! Just started building it now but the mancave is a bit cold as the wife has nicked my gas heater, slow progress! [/quote] Ah, 741s...can't say I miss 'em much. Getting circuit boards done in small quantities is trivially easy these days, but the learning curve on doing your own board layouts can be a bit steep IME. I'm just finishing up my latest preamp build. I'll post some pics and fluff once I get it all together. It's quite similar to the one Chienmortbb is using in the Amp Build Diary thread and there are pics of my boards in that thread.