GENERAL DESCRIPTION. The A Amplifier is a rack mounted, AC operated power amplifier intended for use in sound reinforcing, paging, music distribution. Hi there, up for sale is a Vintage Altec A Tube Amplifier. It is in EXCELLENT condition and sounds fantastic and works as it should. This would be perfect. i’ve read mixed reviews on these online. some say they arent all that special and basically PA amps. i saw some stuff that claims they are good.

Author: Shakasho Mikadal
Country: Romania
Language: English (Spanish)
Genre: Business
Published (Last): 3 October 2010
Pages: 305
PDF File Size: 6.8 Mb
ePub File Size: 11.58 Mb
ISBN: 500-5-91671-659-8
Downloads: 20867
Price: Free* [*Free Regsitration Required]
Uploader: Ketaxe

Again, check out the online articles on that- it’s much easier to explain with pix than in words. With this, however, I wouldn’t go beyond about 1 watt output keep your multimeter, alteec to an AC range, across the dummy load to monitor the voltage- keep it to 2.

PhototoneAug 2, Through Altec Altdc of the Theatre speakers, of course. Sziasztok, MX gyel van valakinek tapasztalata? It would have been helpful if they printed a serial range for each one, and even more helpful if they specified the plate voltages of the el34s. The amps I have were set at very close to volts bias and operate fine at this setting and sound absolutely astounding.

I understand that if I were to run the bias voltage to volts it would lower the plate current but what effect on sound quality and output capacity would result in this change is a mystery to me. Sign in Already have an account?


In addition, some files are archived, so you need WinZip or WinRar to open that files. You can try that for multiple frequencies to get some appreciation of what’s happening across the audio band.

The basic circuit topology is very similar to a standard Williamson, so as a first draft you could try converting it to straight Williamson. Do you think they later changed the original bias spec of vdc to in an attempt to make the amp more bullet-proof and have longer tube life, or do you think they first chose volts and then they felt the plate current just needed to be higher for better operation and sound quality so they revised it to volts?

A guy named Tom Tutay does mods for them. You must log in or sign up to reply here. Most users of tube equipment, unless they’re really into the technical side, never check tube bias anyway. Post or PM if I can help any further. Of course, don’t leave it running like that for too long.

Tubes are all NOS and barely broken in with maybe 50 hours on them. It might be a fun experiment! If you have, or can borrow, a copy of the Radiotron Designer’s Handbook it will give you everything you need to graph virtually anything. Sounds like you want to have some “fun” with this! Register a new account. I have lived and breathed tubes for the past 50 years and still marvel at the amazing things that they can do!

Used altec a for Sale |

Is this a good assumption? If you want to join us and get repairing help please sign in or sign up by completing a simple electrical test or write your question to the Message board without registration. It certainly is possible alttec they decided, at a later date, to run the tubes cooler to increase longevity. Create an aotec or sign in to comment You need to be a member in order to leave a comment Create an account Sign up for a new account in our community.


Also some files are djvu so you need djvu viewer to open them. I’m thinking I should just measure the plate current at either setting and see what value fits the EL34’s recommended plate altce curves the best. These amps were designed to be “bullet proof” and idiot proof.

Compare that to the appearance of the input signal from your generator.

Altec 1568A Amplifier

Sign In Sign Up. You would then need to measure the transformer impedance easy to do with your signal generator to see which provides the closest match. I suspect that you’re not going to see a huge difference.

In most amps, the clipping will not be symmetrical. You need to be a member wltec order to leave a comment.

I recently purchased a pair of Altec A EL34 based mono tube amps.