Vintage Tube Amp

Museum-Grade 1926 Bell Telephone Laboratories Monograph B-204 – Monumental Maxfield & Harrison Foundation of Electrical Audio Recording & The Orthophonic Phonograph. Up for consideration is an exceptionally rare, original August 1926 technical reprint issued during the early operational sequence of Bell Telephone Laboratories, Incorporated. Title: High Quality Recording and Reproducing of Music and Speech. Core Subject: Subtitled “Methods of High Quality Recording and Reproducing of Music and Speech Based on Telephone Research, ” this monumental document is universally recognized as one of the most important papers in the entire history of audio engineering. Authored by Bell Labs acoustic pioneers Joseph P. Maxfield and Henry C. Harrison, this paper details the invention of high-fidelity electrical recording. Moving away from crude acoustic horn recording, the authors applied electrical transmission-line equations and wave-filter theory to mechanical acoustic systems (the “electro-mechanical analogy”). By utilizing condenser microphones, vacuum tube amplifiers, and an electromagnetically driven cutting stylus, this system captured a vastly expanded frequency range (expanding bandwidth by over two octaves). Licensed to the Victor Talking Machine Company and Columbia Phonograph Company, this exact research birthed the legendary “Orthophonic” system, single-handedly saving the record industry from the threat of radio and ushering in the modern era of Hi-Fi sound. &####128142; COLLECTOR’S NOTE ON SCARCITY & RELEVANCE. Holy Grail Investment Tier: Standalone monographs by Maxfield and Harrison on electrical recording are fiercely sought after by audiophiles, phonograph historians, and acoustic engineering archives. As the seminal text that sparked the electrical recording revolution of the roaring 1920s, this August 1926 “B-series” print is a museum-grade centerpiece for any world-class audio or technology collection. Early Sequence Publication: Following Bell Telephone Laboratories’ incorporation in January 1925, this August 1926 publication (Reprint B-204) stands as one of the early sequential monograph releases of Bell Labs’ second operational year. Pristine Structural State: Unlike nearly all remaining institutional examples which were stripped of their covers and permanently chopped or bound into thick composite library collection blocks, this standalone specimen survives un-cut with its full original blue-grey paper wraps intact. Provenance & Condition Report. Provenance: Sourced from the historical repository of the Tri-State College Library (Angola, Indiana), bearing their authentic vintage ink stamp on the front cover. It also features a small vintage pencil notation on the top right corner. Condition: Very Good vintage condition. The interior page block is supple, clean, and free of annotations, highlighting, or structural tears. Factory 3-hole punched at the left margin as originally issued by Bell Telephone Laboratories for vintage binders. Minor cosmetic edge wear and soft age-toning fully consistent with a nearly 100-year-old paper artifact.

Up for sale is a 5 watt amp head I made at A amps. I list it used because it has used mid century HIFI parts, but it is a new creation. A very simple amp with triode pentode combinations in the pre amp. The 6u8a is sharp cutoff pentode triode. I just used the pentode side. You get 2 inputs 2 volume and master volume and a tone control. Not much clean headroom but it can get some distortion going.. Lots of vintage going on with the wood case and transformers from the 1950s, It is wired mostly point to point, very easy to modify. A nice bedroom amp to compliment your pedals and guitar. Amp comes with new power chord. The sound on video is passive pickups into amp into 2 12 inch celestion 75 cab recorded on Imovie macbook.

Brand: RCA (Radio Corporation of America) Model: MI-12181 10-Watt Mono Power Amplifier Serial Number: 2071 Condition: Used / For Parts or Repair (Cleaned & Untested) Up for sale is a highly collectible piece of authentic American broadcast history: a vintage RCA MI-12181 10-Watt tube amplifier. This unit is an absolute dream donor platform for high-end boutique audio collectors, vintage audiophiles, or custom guitar amp builders looking to create a legendary desktop recording rig or low-wattage studio guitar head (perfect for Fender Princeton or Deluxe Reverb style push-pull conversions). This unit comes from a high-quality collection of legacy commercial hardware and features the iconic orange factory nomenclature badge cleanly intact on the rear panel. Key Technical & Cosmestic Features: 6V6GT Power Layout: Factory wired for a push-pull 6V6 power tube configuration, highly sought after by guitarists for its signature warm, organic saturation and punchy mid-range. Multi-Impedance Output Terminal: Features built-in factory speaker taps for 4? , 8? , and 16? Loads. This allows you to plug the amplifier directly into any modern or vintage speaker cabinet without needing an expensive mismatch transformer. Pristine ID Badge: The original factory plate is beautifully preserved and perfectly legible, clearly displaying Model MI-12181 and Serial 2071. Condition Details: Cosmetics: This chassis has been thoroughly cleaned of surface storage dust. It shows beautiful vintage character, original steel patina, and classic retro styling. Testing: This amplifier is completely UNTESTED. To protect the integrity of the original components for its next owner, it has not been powered on or electronically altered. This heavy piece of American iron will be meticulously double-boxed and padded with premium heavy-duty materials to guarantee it arrives exactly as pictured. Please review all high-resolution photos carefully to evaluate the physical layout and inclusions prior to purchasing. Feel free to message.

Presenting a Vintage 1960-63 Vintage Lafayette 250A Stereo Tube Integrated Amplifier. Power about 18-20 wpc. Nice set of tubes on board. (4) EL86 Lafayette branded Amperex Holland / Amperex. (2) Lafayette zbranded 7199 USA probably RCA. (2) GE JAN 12AX7WA (military grade). This amplifier was made in a a era when Lafayette was Made in USA. Check out the cool TV feet on this. Unfortunately its missing one outer Bass Control knob. All controls and switches were cleaned wirk and are quiet. We used a variac to power it up over many hours. It passes a clean signal with no hum playing a CD plugges in the AUX input. Here is a problem. The three 12AX7s are not lighting up. So they are not getting the heater voltage. Possibly a cold connection somewhere. Because of this the problen dual concentric Bass / Treble controls are not responding. At first they worked then stopped after awhile. Its wild how this amp is designed in this manner. The amp will still pass a good signal without these tubes functioning. As with most integrated amp designs. IF these tubes were lit you would get no signal. The volume controls work fine. The volume control is dual concentric. So there are 2 volume controls L & R in one knob seperated so you may control the left and right channels separately or both together. This takes the place of a balance control. There is a STEREO / MONO blend control knob. Which also acts as a ON/ Off when turned fully to the left. Turning far left is STEREO. Turning far right is MONO. Everything inbetween that changes the blend from Stereo to Mono. There is a phase switch. There are also two other switches to contro channell switching that allows you to switch and choose the signal to each amp channel A or B signal on the Left and Right Channel seperately. Another interesting design feature. Well thats about it. With a little work yiu will have a real fine well built vintage Stereo integrated amplifier.

I do a lot of business with them and they always have well cared for gear. Not saying it won’t need adjustments but, it looks like a nice clean unit. Everything you see in the pictures is what is included in this lot. Photos are the best description. Please look at all pictures closely before purchasing. We will document any damage the best we can but the photos will always be the best way to exam the item. Items may need a more in depth cleaning. We will do our best to clean every item, although sometimes we can’t do a full thorough clean. Message us for additional photos or questions. We of course will get them out as fast as we can. We will help resolve whatever issue you are having. We try very hard to provide good communication and always strive for everyone to have a positive experiences!

It is 100% original, in untouched and unmodified condition. This is a mono integrated amplifier with phono equalization settings and the well regarded Wiggins Circlotron circuit. Made in the mid to late 1950s. Rated at 20watts between 20 and 20KHz within 1dB. According to the sales brochure, all DC is removed from the output transformer allowing class B operation of the output tubes. All switching transients are eliminated resulting in the efficient utilization of the output tubes. The impedance of the output transformer is one quarter of that found in conventional amplifier circuits, affording vastly extended range response at full rated power. A damping factor control permits the particular loudspeaker system employed to be perfectly coupled to the amplifier output, eliminating loss of bass from over-damping, or override due to under-damping. This unit has been in my possession for a few years now, but the project pile has gotten out of control and I decided I need to start thinning it. I never even powered this one up (while I’m no expert in tube equipment, I know better than to power up an old unit that has been dormant for as long as this one seems to have been). All tubes seem to be present, as well as all original knobs. Cosmetically, the unit in good to excellent condition (considering its age), with some stains here and there. Please inspect pictures carefully as they are part of the description. The amplifier will be double boxed and surrounded in foam to ensure safe arrival to its destination.

Vintage Original, serviced and working great. Gibson BR-9 10W Vacuum Tube Combo Guitar Amp. This is an original 40′s BR9 it has been serviced and is working great. It’s not the prettiest amp, but sounds great. Still has a 2 prong power cable. Please if you have any concerns feel free to ask!

1950′s VTG Ampeg Bassamp Tweed Tube Amp w/ Jensen P15N Speaker As Is. Been in storage a while. Missing back back panel. Will probably need serviced.

Up for sale is a classic McIntosh MC225 stereo tube power amplifier, one of McIntosh’s most sought-after vintage amplifiers. This example has been serviced and recapped, with attention given to the power supply and critical coupling capacitors while retaining the original dog bone capacitors. The amplifier has been fully tested on the bench and is performing well. It produced 28 watts per channel before clipping, with measured distortion of just 0.04% under the test conditions. Classic McIntosh MC225 stereo tube power amplifier. Rated output: 25 watts per channel. Power supply capacitors replaced. Critical coupling capacitors replaced with Russian K40Y capacitors. Original dog bone capacitors retained. New Tung-Sol 7591 power tubes (Russian-made). Telefunken and McIntosh-branded small-signal tubes. Includes original-style tube cage. The amplifier has been serviced, with the power supply capacitors replaced and critical coupling capacitors upgraded to Russian K40Y capacitors. The original dog bone capacitors have been retained. It has been fully tested on the bench, producing 28 watts per channel before clipping, with measured distortion of 0.04%. Cosmetically, the silk-screen lettering has been erased from the top and is missing in most areas of the chassis. This is a noticeable cosmetic limitation, so please review the pictures carefully. The amplifier is being offered with full disclosure of its cosmetic condition. New Tung-Sol 7591 power tubes, Russian-made. Small-signal tubes are Telefunken or McIntosh-branded.

In original Found condition. Powered on and fired right up and sounds great! Some scratchyness in the pots but easily cleaned up. This amp has NOT been serviced – Just dusted off an tested. The power cord is fraying and should be replaced for safety. Has the original Genelex GEC KT88 1970s power tubes.