Annoying newbie ?s about stereo fet, 2U pultecs, redd 47 micro vs ultra ...

[Romanp]

Greetings from New Zealand.
I am about to order bits and bobs and start my first ever venture into soldering etc.
The only reason I am doing this is because I have been kindly offered assistance from an experienced DIYer.
He has made pultecs (P2P), Drip 660, hairball 1176s, u47 mic, 2 c12 mics etc.

I want to get 2 pultecs, 2 1176s, 2 ez1073s and in the future 2 redd 47s, dual opto and maybe dual vari mu.

I won't have enough rack space for all that unless I can slim a few things down. Eg, 2U Pultecs, stereo fet vs 2 monos and possibly make 2 redd 47 micros instead of 2 redd ultras.
The redd 47 ultras can fit into 2U cases from my net research.

My questions:
1. How challenging is it to make a stereo fet rather than 2 1176s? I would get the hairball parts and Dans case. I don't think I necessarily need stereo linking. I just want to save 2 rack spaces by fitting 2 hairball 1176s into one case.

2. Is there any challenge fitting a pultec into a 2U case vs 3U?
The photos I have seen suggest there is plenty of spare headroom in a 3U pultec case. Is it just a case of using a smaller case?

3. What would be the sonic difference between the ultra redd 47 mic and the micro version. I could fit 2 micro redd 47s into a 2U case vs 2 separate 2U cases for the ultra redd 47.

4. Will the drip dual opto fit into a 2U case?

Thanks,
Roman.

 

[baadc0de]

Ah, a rack-space-saving man after my own heart

A pultec 2U:


Totally doable, you can follow recproaudio's layout found here http://www.recproaudio.com/diy_pro_audio/diy_files/eqp_1a/eqp-1a_layout_final.jpg instead of buying expensive PCBs. You're not really saving that much time with PCBs for such a simple tube circuit anyway in my opinion. And the heat dissipation is going to be better and not affect the PCBs since they are so far away.

So, this is how it looks like in the end 2U for both designs


For the REDD, I actually wouldn't go with drip's PCBs, I did - it was my first project, but I wouldn't again. You can make them easily like I did the pultecs, using cheap turret boards. That said, I had lots of different power supplies in my REDD and I like it best without the 0a2 tubes. Some people I've heard from locally do them with solid state power supplies and are happy, noise-free users.

For a dual-la2a I would recommend volker's dla2a PCB more because it's compact and has support here. I implemented one here in GMA case, though I did later change controls to below the VU instead of above the VU, so I can actually look at what I'm tweaking. Noobie mistake


All in all, I did a lot of projects from drip: two REDDs, two Altec's later modded to EMIs, a Fairchild 670 and I still have two BA6As to make. And so far I'm not really thrilled by his support. On the other hand stuff that is supported on these forums, I have had much more luck on. We have together solved quite hard to spot errors. I like his manuals, but some of them have errors and the response time on questions is not that good. But what can you expect it's one man for the whole world, here we can share the load.

 

[Shattersignal]

I built a mono 1176--rather easy on its own.  My buddy build a stereo 1176 and got hung up badly on the matching and calibration of the two units.  Matching and then calibrating a stereo 1176 can be quite a tricky task. 

I might humbly suggest taking on one of these build projects at a time to avoid getting overwhelmed right off the bat.  My Pultec was an extremely easy build and I'd wholeheartedly recommend that as a first foray. 

Also, remember that if you're ordering custom transformers (e.g. from Sowter), there's a bit of lead time needed, to factor in.  But needless to say--it's totally worth the wait.

I'm still a beginner myself, so I figured my perspective might be close to yours and might be valuable for that reason.

BTW--great choice going DIY!!