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[bblackwood]

Incredible. Marchand sent a (hand written) sheet of paper with the stereo matching with my attenuator, iirc it was matched to 0.1dB as well.

Are those JLM Audio line buffers there? How do you like those?

[Gold]

Are those JLM Audio line buffers there? How do you like those?

I like the functionality because you can use chips or discrete op amps. I decided I wanted the topology of the Input and Output Amplifiers to be line receiver-attenuator-line driver. I thought it provided the most flexibility for experimentation. I didn't want to box myself into a corner by committing to a topology that would have to be scrapped to be changed. This meant going with the giant switches instead of a less expensive solution.

The boards are clever but utilitarian. Change the amplifier and change the sound. It is a four resistor differential line receiver. John Roberts burst my bubble by saying it is unbalanced if the definition of unbalanced is both legs having a common impedance to ground. Most would call it a balanced receiver because it is differential but the CMRR is not nearly as good as fancier topologies or a transformer.

[jamesfei]

How do you like the Electroswitch C4's? The P&G is a nice touch.

Not nearly as elaborate as your console, but here's a picture of mine before it got wired up (gain offset in 0.5dB's, 5 inserts, including one MS loop with variable gain and one pair that can be swapped in order. The Alps pot is for the headphone amp.)



And the finished console:

[Gold]

How do you like the Electroswitch C4's?

I like them. I went with them because they were the least expensive switch that was high enough quality. They have a clunkier feel than a Grayhill 54 or Electroswitch C5 but you can run over them with a truck. To do it in C5's or Grayhills would have been about 3k more.

That's a nice looking console.

Edit: That's a nice Wohler Metering unit you have. I like those things.

[jamesfei]

Thanks Paul. The meter is actually made by B&B. The scope isn't great if you're used to a good scope (I see you have a HP 1200 as well--which has a very sharp trace), but fine for basic X-Y monitoring. Above it is my Pico compressor.



Thought you might get a kick out of this Daven (7 Pole Bridged-T), it was the master fader for an old cinema install. Not as impressive as that full-H Shallco, but the wirewound resistors are nice:

[Bonati]

Hey James - I think the earlier versions were made by B&B and the later ones by Wohler? That's my guess. Did Wohler buy B&B at some point? Don't know a thing about a history of these companies. I have three of these units and they all say Wohler on the front and B&B on the back panel. Also looking for a manual - ever seen one? For other parts, the festoon bulbs for the VUs are easy to find but have you ever had to replace the CRT?

If anyone's looking, the trick for buying a used one is to make sure none of the scope positioning knobs are broken off. One always seems to be broken off - the past 10 I've seen on eBay have been that way. I guess you could replace it but it's pretty packed inside that enclosure and I'm lazy. Sorry for the miniature distraction - back to worshiping the 1" Studer!

[mpdonahue]

Hey James - I think the earlier versions were made by B&B and the later ones by Wohler? That's my guess. Did Wohler buy B&B at some point? Don't know a thing about a history of these companies. I have three of these units and they all say Wohler on the front and B&B on the back panel. Also looking for a manual - ever seen one? For other parts, the festoon bulbs for the VUs are easy to find but have you ever had to replace the CRT?
If anyone's looking, the trick for buying a used one is to make sure none of the scope positioning knobs are broken off. One always seems to be broken off - the past 10 I've seen on eBay have been that way. I guess you could replace it but it's pretty packed inside that enclosure and I'm lazy. Sorry for the miniature distraction - back to worshiping the 1" Studer!

As far as I know, these things were always made by B&B systems.
B&B systems are still in business and will repair the AM series meters.
http://www.bandbsystems.com/
I have an AM3B and all 4 pots were broken off. Funny thing is that once I calibrated the scope , it hasn't been touched in almost 5 years. I was lazy like you so rather than replace the pots, I just took out my dremel and cut a groove in the broken shaft so I  could tweek the pot with a greenie. I actually find that it is better without the adjustments on the front panel for somebody to accidentally change.
All the best,
-mark

[jamesfei]

Hey James - I think the earlier versions were made by B&B and the later ones by Wohler? That's my guess. Did Wohler buy B&B at some point? Don't know a thing about a history of these companies. I have three of these units and they all say Wohler on the front and B&B on the back panel. Also looking for a manual - ever seen one? For other parts, the festoon bulbs for the VUs are easy to find but have you ever had to replace the CRT?

Hi Josh: I've never seen a Wohler branded version of the scope meter (mine is the AM-2B), and don't know the relation of those two companies. Also, thankfully, I've never had to repair the scope portion. The pots are easy to replace, but I'd watch out for dead CRT's if buying used, it might not be worth the cost of repairs at this point. You probably know this already, but there are a set of trim pots to calibrate the levels for the peak/vu meters and x-y.

[waltzingbear]

just wandered onto this thread. Nice work Dan, and great job Paul.

a note re cartridges, you should try demaging the carts to see if they aren't getting magged by the way you use them. Various ways to do this, including running a ramped 5hz or lower tone thru them (with plenty of level), ramp the turn on and off. If you have a hp200cd, try that as your source.

also thought I should add these pictures of an old school disc mastering  console that I have kicking around here, the guy I got it from said it was from United Western, but I can't necessarily believe him. Definitely from LA.

Alan Garren
Waltzing Bear Audio

[Gold]

you should try demaging the carts to see if they aren't getting magged by the way you use them. Various ways to do this, including running a ramped 5hz or lower tone thru them (with plenty of level), ramp the turn on and off.

That's a very good idea. It could save me some money and the time fiddling with tiny mounting screws. I just installed a new cartridge yesterday. I can probably dig the old one out of the trash and try it.

[Gold]

In the last two weeks I've done five albums direct from tape to lacquer. That's way more than usual. None from 1" but that's not too surprising. It's so much more fun than the regular way.

[bblackwood]

That's awesome new, Paul.

Do you have a full A/B path now or is that still a work in progress?

Very cool rig you have...

[Gold]

No A/B console yet. A few weeks ago I made some good progress on redoing the BP EQ. I had wanted to make it as a six band EQ by splitting out the shelving sections. The bus became too long and oscillated so I'm redoing it as intended. I hope to get to work on it this weekend but that's what I say almost every weekend. Work intrudes. When I get that prototyped that's everything except for the A/B switch which I'm contracting out. Then I'll start doing systems inteface type stuff to see if my plan is going to work.

I'm doing them now with my regular two channel setup. Changes on the fly. Preview offsets to pack the grooves. Gotta be on my toes.

[bblackwood]

Sounds fun. You should shoot some video of yourself cutting a side sometime so we can watch - I know I'd enjoy it.

[Gold]

I'll try to make that happen. I think it would have to be someone else. For these I have to keep focused even while I'm twiddling my thumbs waiting for the next song.