I started a Revox A77 restoration project a while back. Still not finished. Similar quality, except mine is the older low speed version with quarter track stereo heads and 3 3/4 and 7 1/2 ips speeds. This B77 is the later, high speed version with half track heads and 7 1/2 and 15 ips speeds. Instead of this, however, what I would much rather purchase is a used/repairable high speed version of the much older Revox G36 (tube) R2R with a factory supplied half track head assembly that can be re-lapped. That would be quite the machine, if I could find one. Only problem is that the relapping service that can do this type of work is now long gone.
@Nicholas_23 said:
Honest question , what are you guys doing with these R2R units when up and running ?
When I was younger, I did some on-location recording of live events using two high quality microphones. If I can get something running, my thoughts are to perhaps try to do some live events again, like Christmas concerts, or local band performances. I have a Roberts 1630 stereo R2R vacuum tube recorder that is in fairly good shape that I plan to restore. It is 1/4 track stereo with a very simple circuit that only uses 5 tubes. It is a low speed 3 3/4 and 7 1/2 ips machine, but can be modified to do 15 ips with an accessory kit that replaces the capstan bushing and pinch roller.
BMR tower knockoff coming along nicely. Too bad these BMR drivers are NLA. RS-225-4 and GRS tweeter
One of the nice things about those BMR drivers is that they provide a very good horizontal directivity match to a non-waveguided tweeter like you have going there. I hope that PE considers bringing them back again someday. I'm kicking myself for not having ordered another batch of these before they went NLA.
One of the nice things about those BMR drivers is that they provide a very good horizontal directivity match to a non-waveguided tweeter like you have going there. I hope that PE considers bringing them back again someday. I'm kicking myself for not having ordered another batch of these before they went NLA.
Me too. I almost ordered 10 when I got these and didn’t because there were about 250 left at the time.
Which model of BMRs are they? If you REALLY want some more, Soundimports (in the Netherlands) has some of the models in stock. I've ordered twice from them and shipping was actually quite reasonable. (That may not be true anymore with higher shipping costs and tariffs since the time I ordered.)
As a fall back, I'm thinking about picking up a batch of these 2" BMR's that @DrewsBrews was experimenting with. But they are currently out of stock with a note about price uncertainty due to the tariff situation. Bummer. Think that they might make a good, cheap non-waveguided MMTMM or MMMTMMM with the right tweeter. Priced at US $6.70 each at 4+ quantities, the cost should not be too bad, even with tariffs added on.
Correct spelling is important, but can also be amusing: consider these signs from a nearby pub before its change of ownership to a more family friendly venue:
menu items included "stek" and "trote", whatever they were;
drinks included "dite beer";
on Friday nights, the alleged 'entertainment' included "stripers" and "topples barmaids"
FD and DT seems to largely still be seperate stores. The FD/DT stores seem more rare. The ones I've been in they seperate completely into two halves. Left side FD, right side DT. But you can freely walk around everywhere as there is no wall between. It is a bit strange.
But to find one of those literally right next to a DG seemed like a glitch in the matrix moment.
Skip to around 6min mark if you don't need/want the e-cap construction and use explanation.
Working for min wage and in college, I remember finally being able to afford one of those Shuttle "barebones" mini PCs; because I bought it off ebay with blown caps. Then purchased and soldered in replacements. "badcaps.net" was the site where the guy running it would do the research to find which caps were from reliable sources and sell those to folks to repair failed equipment.
Fast forward several years: At work our server that ran the backups went down. The raid card had failed and they were NLA from the manufacture. Also replacing the card would mean losing all the backup data as the config was on the card. So I wasn't too keen to replace with a used ebay part that would probably fail soon after rebuilding the array. I noticed one of the caps on the card was bulged so I pitched the idea of replacing them to my boss. Ordered in caps, picked up a $5 soldering iron and gave it a shot. It worked for several years until they were able to afford replacing the whole system.
That picture reminds me of Fair Radio Sales in Lima or Mendalsons in Dayton. How long has that Ax Man been at that particular location in St. Paul? I always stayed about a mile down the road on University Avenue when I was detailed to MSP in the 1980's.
St. Paul was the initial location and it sounds like it's been open since the 60's. I took my 5-year-old son there today which brought back memories of when I would go there with my father many years ago.
I agree. I always like to stop there on my way to the SDC (MWAF). And Fair Radio Sales is now gone too. Always liked to stop there on my way as well. Do they have an Army Surplus electronics store like Ax Man near Ft Wayne?
Comments
I started a Revox A77 restoration project a while back. Still not finished. Similar quality, except mine is the older low speed version with quarter track stereo heads and 3 3/4 and 7 1/2 ips speeds. This B77 is the later, high speed version with half track heads and 7 1/2 and 15 ips speeds. Instead of this, however, what I would much rather purchase is a used/repairable high speed version of the much older Revox G36 (tube) R2R with a factory supplied half track head assembly that can be re-lapped. That would be quite the machine, if I could find one. Only problem is that the relapping service that can do this type of work is now long gone.
Here is my old A77 thread in case anyone is interested:
https://techtalk.parts-express.com/forum/tech-talk-forum/67509-revox-a77-restoration-project
Honest question , what are you guys doing with these R2R units when up and running ?
I admire your ability to rebuild one of these units. While I find turntables interesting, R2Rs are classic (and no snap, crackle, and pop).
When I was younger, I did some on-location recording of live events using two high quality microphones. If I can get something running, my thoughts are to perhaps try to do some live events again, like Christmas concerts, or local band performances. I have a Roberts 1630 stereo R2R vacuum tube recorder that is in fairly good shape that I plan to restore. It is 1/4 track stereo with a very simple circuit that only uses 5 tubes. It is a low speed 3 3/4 and 7 1/2 ips machine, but can be modified to do 15 ips with an accessory kit that replaces the capstan bushing and pinch roller.
BMR tower knockoff coming along nicely. Too bad these BMR drivers are NLA. RS-225-4 and GRS tweeter

aaa> @Colonel7 said:
One of the nice things about those BMR drivers is that they provide a very good horizontal directivity match to a non-waveguided tweeter like you have going there. I hope that PE considers bringing them back again someday. I'm kicking myself for not having ordered another batch of these before they went NLA.
Me too. I almost ordered 10 when I got these and didn’t because there were about 250 left at the time.
Which model of BMRs are they? If you REALLY want some more, Soundimports (in the Netherlands) has some of the models in stock. I've ordered twice from them and shipping was actually quite reasonable. (That may not be true anymore with higher shipping costs and tariffs since the time I ordered.)
Tectonic TEBM46C20N-4B. Parts Express #297-2157
https://www.parts-express.com/Tectonic-TEBM46C20N-4B-BMR-3-Full-Range-Speaker-4-297-2157?quantity=1
As a fall back, I'm thinking about picking up a batch of these 2" BMR's that @DrewsBrews was experimenting with. But they are currently out of stock with a note about price uncertainty due to the tariff situation. Bummer. Think that they might make a good, cheap non-waveguided MMTMM or MMMTMMM with the right tweeter. Priced at US $6.70 each at 4+ quantities, the cost should not be too bad, even with tariffs added on.
https://www.parts-express.com/Tectonic-TEBM35C10-4-BMR-2-Full-Range-Speaker-4-Ohm-297-216?quantity=1
Wow. Maybe I should have kept those extra 2" BMRs I got for Christmas.
Correct spelling is important, but can also be amusing: consider these signs from a nearby pub before its change of ownership to a more family friendly venue:
menu items included "stek" and "trote", whatever they were;
drinks included "dite beer";
on Friday nights, the alleged 'entertainment' included "stripers" and "topples barmaids"
Geoff
Washed and waxed the Mighty Sorento today. Weather is beautiful.
Snapped this pic yesterday heading up to family in Muncie.
The Trifecta.. A venerable Dollar Mecca!
As you likely know, FD has been sold by DT.
InDIYana Event Website
FD and DT seems to largely still be seperate stores. The FD/DT stores seem more rare. The ones I've been in they seperate completely into two halves. Left side FD, right side DT. But you can freely walk around everywhere as there is no wall between. It is a bit strange.
But to find one of those literally right next to a DG seemed like a glitch in the matrix moment.
How about that? Three places in a row where you could buy expired food.
Skip to around 6min mark if you don't need/want the e-cap construction and use explanation.
Working for min wage and in college, I remember finally being able to afford one of those Shuttle "barebones" mini PCs; because I bought it off ebay with blown caps. Then purchased and soldered in replacements. "badcaps.net" was the site where the guy running it would do the research to find which caps were from reliable sources and sell those to folks to repair failed equipment.
Fast forward several years: At work our server that ran the backups went down. The raid card had failed and they were NLA from the manufacture. Also replacing the card would mean losing all the backup data as the config was on the card. So I wasn't too keen to replace with a used ebay part that would probably fail soon after rebuilding the array. I noticed one of the caps on the card was bulged so I pitched the idea of replacing them to my boss. Ordered in caps, picked up a $5 soldering iron and gave it a shot. It worked for several years until they were able to afford replacing the whole system.
A few pics of the old electronics at Ax Man in St. Paul.

Chilling at The Feral Goat tonight.
This makes me want to do a shed pub so bad.
I've been to Ax Man a few times over the years while visiting my brother. I don't think we ever made it to the St Paul location.
That picture reminds me of Fair Radio Sales in Lima or Mendalsons in Dayton. How long has that Ax Man been at that particular location in St. Paul? I always stayed about a mile down the road on University Avenue when I was detailed to MSP in the 1980's.
St. Paul was the initial location and it sounds like it's been open since the 60's. I took my 5-year-old son there today which brought back memories of when I would go there with my father many years ago.
Ah yes Mendelsons. So much there I never knew where to start.
Ax Man is fun. I used to go there in the 80's.
Sucks Mendelsons is no more.😢
I agree. I always like to stop there on my way to the SDC (MWAF). And Fair Radio Sales is now gone too. Always liked to stop there on my way as well. Do they have an Army Surplus electronics store like Ax Man near Ft Wayne?
way back about 15 years ago, Pembleton's/Meisner's closed.
I used to get resistors and caps there a lot.
I don't know of any others in the area.
InDIYana Event Website
The internet had a lot to do with the closure of those kinds of places.