Bi Amp Model 19's and More??

[SURE-FIRE]

New Member here. Congratulations on a wonderful informative board.How would I go about bi-amping my Model 19's? Could I use Jbl Crossovers? How about adding a JBL 077 for more top end? Crossover points? I was thinking out changing out the X-over caps with Relcap Theta's, anyone tried that? Any help appriciated.

Brian

[Altec19]

Much of the Model 19 "sound" is due to it's crossover. It's more refined than what Altec typically used and has some unique qualities. Don't be too quick to discard it. One easy crossover modification that I (and others) have found to make a significant difference is to eliminate the L-pads from the circuit. One can be completely bypassed and the other replaced with a single fixed resistor. Do a search of the forum for a more complete discussion.

[Altec19]

Here is the thread I was referring to:

Link to Model 19 crossover thread

[boltupright]

I tried Bi-amping mine & I wasn't happy with biamping mine the way they were, I ended up flipping them upside down & running 511 horns & crossing over at 500hz & they sounded much better, I sold my Quad II mono blocks that were powering the horns, & went back to running the 19's stock with the crossovers & they sounded just as good to my ears.
I run a very high end mosfet power amp & it smoothed out the top freqs as well as the tubes.

[Altec19]

boltupright makes an excellent point. If you don't like what you hear coming from a pair of 19's, be willing to examine each link in the chain. They are a very revealing speaker and you WILL hear the difference between various amps, preamps, and source devices. Make sure the speakers are functioning up to their original capabilities and then consider the electronics driving them before getting into any significant modifications. An amp that sounds fine driving a lesser speaker may sound bad driving 19's because you are now hearing everything that the amp is doing. It's not a fault of the speakers.

[Brek]

I bi-amped my Santiagos using the Altec 1632A Xover. I'm very happy with the results.

Though at times I do stack some DQ10s in series with them, to get a more refined soundstage, and better imaging. It's still a work in progress.

When I really want to rock out at concert levels, I hook the 811s to my 100wpc 9442A Altec amp and drive the 411s with a 270wpc pro amp.

Sweet

[SURE-FIRE]

I'm powering the 19's with pair of mono bloc DIY SET WE300B Amps ~ heavy power supply, custom output transformers and 50's WE tubes @ 7 watts output ~ Midrange magic is incredible, the players are in the room with you, superb imaging, the speakers disappear, just the instruments playing in there own space.....but the bottom end could be a lot more solid. I have a Adcom 5800 amp 250/250 8ohms ~ 450/450 4ohms. When I hook it up full range, I get ALL the solid bottom end I want, but the midrange magic totally disappears and im back to a point source horn sound again. I have a collection of other tube amps that I use from time to time: ~ Mac 30's ~ Mac 60's ~ Heathkit W5-M's ~ Radio craftmen C-500's ~ Eico HF-14's ~ A pair of williamson 807 Monoblocs ~ None come CLOSE to the sound of the 300B amps. If I could use my 5800 on the bottom and the 300b amps on the top, that would be ideal. How would I go about doing that? Brian

[zelgall]

I hate to admit it here but I'm now bi-amping my 19's. I use a Marchand Xover at 800Hz and 300B's on the bottom, 2A3's on top. I tried 1400,1200, 1000Hz just because it's easy with Marchand. I have also tried a variety of passive arrangements including line level but I think the actives are the way to go. The stock crosovers are still there and I can switch back easily, however I don't think I will. One other possibilty that I'm looking at right now is putting the crossovers in the driver stage of my amps. I think this makes more sense because you can know for sure what is before and after the Xover. Everyone, please feel free to jump all over this post.

[run]

Hello fellow Altec 19 owners,

In my experience the quality of capacitors used on the crossover makes a huge difference in the harshness that can occur in the upper midrange. I started out with Solens bypassed with Jensen pio and while this was an improvement over the stock caps, they still sounded harsh on many recordings. I recently replaced the Solens with Auricaps bypassed by Jensen pio and the difference was not subtle. The speakers are still unforgiving of poorly recorded material but they now have that "you are there palpability" that Altec 19's are known for. I have a hunch that the best caps for the Altec 19's are the ASC motor caps (or any vintage pio motor caps)that other members on this board have used. They are cheap but big. What's my point? If the caps used on the crossover are the best suited to this design, then one can get away with using a wider variety of amps (not just sets). Gainclones sound great on 19's but other solid state (in my exerience) usually sounds harsh. Non-oversampling (ie: Scott Nixon)dacs also do well on the 19's. Get the crossover caps right and use a wider variety of amps.

p.s. I bypassed my lpads initially and then recently put them back in the circuit as they were far too revealing.

Regards,

Pat McDermott

[run]

Hello boltupright,

Sorry, I didn't mean to dis your amp. The ganiclone is solid state and cheap to build and it sounds great as well. Sounds like you've got a nice amp.

I have included a link to the Scott Nixon site. I used a similar design to this one and the results with a tube preamp were very impressive. You can find links on the internet for DIY schematics. A word of advice though. Don't go nuts with the audiophile parts. The sound is more laid back without Black Gates, Rikens etc. Use Panasonic electrolytics and carbon comp resistors. You can build one of these for about $200.00-$300.00.

http://www.scott-nixon.com/dac.htm

You would have to spend thousands to beat the sound of these amps. They like efficient speakers and they have rediculously good bass response.

Regards,

Pat McDermott