garyeanderson

I cut it about 1/16 oversize and glued it in place, I added 3 more clamps after I took this picture. I gave a bit over an hour and sanded and routed the edges with an 1/8 inch round over bit. By 2 o'clock it was ready for paint, just I was setting up the stuff to paint, the snow flurries started so I had to do something else. It had been 6 months since I changed the oil in the diesel pickup so I went and got an oil filter and a fuel filter, $58 and 30 cents - I could have bought another amp. When I got back home the flurries had stopped so out came the paint and spray gun. 30 degrees is a bit cool for Rustolium 7777 so I sprayed the inside of the top and dragged inside to warm up, when it had tacked up out it went again to finish off the top Over night the paint dried and this morning I installed the perforated metal grill. Looks ok and fits even better... I may be done but I am sure I'll have the bottom of the amp off again, at least I'll have a nice stable base for it to rest on. Gary

Hi Seti It may happen, I am not tired of looking at it yet, If/when I get some prices on re-storing the Altec then I should know more. Back to the Bogen now, Sunday I cut the sides for the amp cover. I had a bit of Baltic birch left over from starting to build the Klipschorn side grills so I grabbed the two pieces. I thought there would be enough but only got three sides, the forth was a cutoff from some scavenged record player that I had my way with. There would have been enough but I changed the design and rabbited the bottom so it would fit over the amp. That meant I had to miter the corners so the rabbit would not show. I don't have corner clamps so I just glued them on the counter with wax paper under them and held them in place with a square to indicate I was close enough for a minute and left the house for an hour, when I returned - I repeated it twice more. By evening I had the open box below. When morning came I rummaged around looking for the top. Looked at some old drawer bottoms but they were I/4 inch lauan but I wanted something a bit thicker. Anyhow the guy I got the DB-20 from had a couple of speakers in the back of his truck that he was going to toss in the dumpster at work, one was a KLH model 5 so I grabbed that one and the other was a no name speaker that was made in Romania, I figured I could get rid of it just as easy so that came home too. I had pulled the back and the veneer was lifting so I set it aside, the rest was a plastic veneer on particle board and I pulled the woofer and knocked down the cabinet and junked the rest. I save the back as it looked to be Baltic birch and you never know when you need a hunk to cut up. I thought it would work for the top and it had a hole for the speaker terminals that I could loose when I routed the opening for the air vent grill. I needed the template to route the air vent and looked around and I saw the pattern I used before (looks familiar? a Khorn side grill )

They seem to weigh about the same, lots of iron like substances in both. UPS would love the trade, buy stock now... What I saw for $90 was a aftermarket paper cone for the woofer, the $130 was "altec" paper cone. I have an old Magnavox FM-13 table radio that would be just the thing to power the Cornwall clone with the 605B https://www.radiomuseum.org/r/magnavox_fm13.html I think there are 6 Bogen PA amps in the collection, the H30 is pretty cool also - those brown t u r d s were swapped out for those orange drops. Bogen was a great name and innovative to keep prices as low as the could to keep market share - just like klipsch did.

Randy Thank you for this great info Gary

Hi Randy Not quite that old its a 605B so late 50's to mid 60's or so I have read. I am not sure what I will do with it, I have never re-coned a speaker let lone one with a compression driver built into it. I have seen aftermarket kits for about $90 and "altec" ones for $130 and that just for the woofer, the high frequency I did not see. I am guessing it would cost 3 to 5 hundred to have it repaired and that is not in my budget. I got it because it "looked cool", the owner said it worked the last time he used it (bass player). I will have to think about it for a while, it may just sit on the shelf as a conversation piece. Gary

Hi Maynard I did not get it for High fidelity use, I don't plan on doing much more than I have done. It was used as a Bass amp and I plan on using it for a guitar amp (I know kind of sacrilegious, but I am a heathen). Anyhow, I took the bottom back off after playing it for about an hour and did some probing with the volt meter and did not like what I was reading, what had been marginal was now over spec. The 441VDC was now 461 VDC so I reconfigured the first leg of the caps before the choke and installed a pair of serial 22uf caps with 2 - 270k ohm resisters between. This brought up the next problem. the voltage of the cap after the choke way now 451 VDC so I quit and went to bed. When I woke up, I went back to it and repeated the same thing after the choke. and moved the 10uf cap that was on the plate to the screen. The voltages had jumped up to 473 VDC off of pin 2 of the 5U4 rectifier and 461VDC on the plates of the 6L6's, the screens were around 363VDC, Cathode is at spec of 14 VDC and the grid is also on spec of Negative 10 VDC. I measures the 417h VAC off of the transformer which seems a bit high seeing I was measuring 123 VAC at the wall vs. 117 which the amp was designed for. some discussion of the DB-20 below https://el34world.com/Forum/index.php?topic=13511.0 https://el34world.com/Forum/index.php?PHPSESSID=gfcenspkbgsegp6k4uhl799ej6&action=dlattach;topic=13511.0;attach=29160

I guess I should say this again as folks seem to have missed it - I do not want to ship these empty Heresy 1 cabinets. So as they say "pickup only" call 781 206-012Nine before 7 pm if you would like to see them or any of the other speakers that I have listed recently, the Cornwall's and LaScala's are sold, I delivered them Locally and will likely do the same for any of the larger speakers, Khorn's or Corn Clones. Thanks again for helping me Gary

I replaced the power cord as it was cracked and I didn't trust it. It wasn't long after before I powered it up. One of the 12AT7 tubes was dead so that was swapped out (all I could find was a 12AX7) and it was making noise again. now I need to figure out what to do with the Altec , the high frequency horn is open and the woofer is showing 50 ohms and if I push on the cone slightly it goes off the scale.

I got a few Q-tips and the acetone out to clean off the wires, it was working but the Q-tips were falling apart so I found a small brush and continued. Once I could follow the colored wires I saw what looked to be two wires going from the same places so I unsoldered one to ohm them out. At this point I replaced the both 8 MFD caps with some new 10 MFD caps. This picture is off the internet and is much, much cleaner

The DB-20 had all of the tubes and the owner said he had last used it around 15 years ago and played bass through it, I kind of know what 15 years means so I opened it up to see what was inside It took a while to figure what was going on, the 8 mfd can cap that is just before the choke was bypassed so that just the choke and second 8 cap were all that were stabilizing the 441 VDC. It was made even harder to figure as all of the wires from the power transformer had grown a white layer of crud.

I have the bad habit of doing a search for "tubes" on craigslist. New Years Day this DB-20 was listed at midnight for $50, there was a phone number ( I will rarely email, unless its just listed and I want it bad ) and I called. Made the appointment for 11am and brought it home. Before I left I spied this old Altec 605B and commented that it looked pretty cool and as I handed the owner the $50 for the Bogen, he said "take it"

Hi Ben I believe Colin was the name of the person I bought them from and I picked them up in Salem, Mass. Colin had a pair of JBL or EV horns (I have a picture on another computer) and was using them in a two way configuration. I could not persuade him to sell the horns with the bass bins, I started collecting parts to build up a stock KC-FR with the AK-3 networks, K55-M squawker and K77-M tweeter. I thought that I would give folks the option and will sell the bass bins with or without. I made the tops (bought the top grills from a forum member) And have started on the side grills. Give me a call if you would like to see them. Gary

I pulled one of the hatches to see what woofers I had in these. Amy how I took a picture so others could see too.

Thanks Randy , I'm not thrilled with how I made them but there ok. When/if I ever get them done you won't see much of them anyway. I started out taking the best of the 4 grills I had and stripped off the fabric, then pulled the 500 or so staples so that I could copy it. I made a router template and there was little way to fasten it. It appear that I made one and gave up. I used a table saw and plunge cut what I could on the other three, then I wait a few months as my jigsaw was at my mothers vacation home. After posting the first couple of pictures this morning I went home and had a treasure hunt up in the attic and after about 10 minutes I found the other L bracket still attached the triangle. I used one of the triangles as a template and drilled the pilot holes for the screws. I put all 8 L brackets on and then put them away for a while. I need to find a pneumatic stapler for those little 1/4 inch staples that Klipsch used.

I brought them in so they would finish drying and this morning I pulled off the tape. Just to see how hard it was to assemble I tried one this morning. I'll get the other three done and if I know myself they will likely set around for a while longer before I get the grill cloth stapled on to them.

I bought khorn decorators a few years back (5 or was that 8 now?) and they were just the bass bins and the top to seal the corner. A couple years ago built the tops to turn them from KD-FR into KC-FR and then the project stalled for a while, I got back to it and started on the side grills because I had bought some 12 mm Baltic birch for another project and I had some left over so I cut them to size and beveled the edge and it stalled again for other reasons. yesterday was very nice day near 60 degrees so I thought it might be nice to get back to it and get the pieces painted. I looked around for the triangle pieces and was missing one so after looking at the broken set that I had it was just easier to make new ones. At the moment I am only missing one L bracket and a pair of wing nuts, anyway it was near 50 by noon and I had all of the pieces sanded and ready to paint. I got out the Rustolium 7777 satin black and went at it with HVLP spray gun. You can see the tape I put on so I could glue and screw them together. I guess I should have assembled them first but if I had, they would likely still not be painted as the day was pretty short and the temp was going to drop pretty fast as the sun got lower in the afternoon.

more early spring cleaning to do - so I got 3 pair of Klipschorns and one pair is just not in the plan due to a lack of corners and I have some other speakers that I would like to play with. I bought these (4L874 and 4L875) as bass bins and have been collecting parts for the rest. They were built as KD-FR with birch plywood fronts. I have collected some AK3 networks to go along with the K55m/K400 and K77m and built up the KC style tops. I will sell the bass bins by themselves for anyone that has the upper frequencies covered - Price for the pair of bass bins only is $800 If you want more than just the bass bins then we can talk when you come to inspect. Call me (no txt please) at 781 206 012nine - mornings and afternoons are best Thanks Gary

I have re-capped three or four Klipsch networks (Belle's, Cornwall's, Klipschorns) with Solen's from Bob (I believe) and have always been somewhat disappointed a the results (or lack of). To my ears I didn't notice any improvement in any of them. So this time I just thought I would try the cheap route. I will likely just un-do what I did. Then again, I have been reading about the F20 sub and if I were to decide to order the woofer I could also toss in some new Daytons or the like. I still need to divest of a certain stock of Klipschorns before I build anything though

On Wednesday I happened to be going by the local (30 miles) electronics supply so I pulled off of the highway and went on in. I wasn't expecting there would be much of a selection of brands of capacitors but I figured I could get some 1 mfd and maybe some 2 mfd. I studied what was on the display rack and thought that as long as I was there I would just get what they had. So for $3.04 I got enough to do both C type networks. I didn't have high expectations of these NTN capacitors being "musical" but for the money it couldn't hurt. So yesterday I put them in and played the H 700's for a couple hours. To be honest I could not tell the difference. I did the first one, reassembled, and played so I could A - " B them. I then did the other just so they would match. I left the old oil can caps in place "just in case" I wanted to go back. There are two conclusions that I can draw from this, the new ones are no better than the 46 year old oil cans OR my hearing is just plain bad.

I installed the backs and started to play them, they sound a bit on the dull side. I guess its time for some new caps I lost track but I think I now have 6 coats of boiled linseed oil, it is still taking some in but the urgency seems to be gone.

yes, stop by and have a look. Gary

I removed the K55m and K77M squawker and tweeter and reinstalled K55V and K77

My plan at the moment is to continue with my plan of two more coats of boiled linseed oil in the upcoming week and get the backs installed. Then I hope to listen for a bit before I do anything more.

If I repeat this another 3 or 4 times they will start to look good.