Advent Loudspeaker efficiency?

I'm at my friend's hunting cabin this weekend. I thought it would be fun to bring a EL34 integrated amp with me as an "upgrade" to the 1980's Panasonic baby blue all in one stereo he's been using there since we were kids. To my surprise, the EL34 amp won't drive the speakers well at all. I had to crank the volume knob to 80% of full volume to hear anything so, I'm guessing that the speakers are power hungry? Reconnected the baby blue Panasonic and they play fine.
Sources: Technics SL1200MKII | SME3009 Tonearm | Monster Alpha 1 MC cartridge | Oppo UDP203 disk player | Nikko NT-790 analog tuner | Musical Fidelity Trivista 21 DAC | Preamp: Threshold SL-10 | Amplifier: Threshold Stasis 2 | Speakers: Snell Acoustics C/V | Kimber 12-TC bi wire speakers | Analysis plus Oval 1 preamp to amp | Wireworld Eclipse 7 DAC to Preamp | Wireworld eclipse digital IC Oppo to DAC | Audioquest Quartz tuner to preamp |

Answers

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    Sources: Technics SL1200MKII | SME3009 Tonearm | Monster Alpha 1 MC cartridge | Oppo UDP203 disk player | Nikko NT-790 analog tuner | Musical Fidelity Trivista 21 DAC | Preamp: Threshold SL-10 | Amplifier: Threshold Stasis 2 | Speakers: Snell Acoustics C/V | Kimber 12-TC bi wire speakers | Analysis plus Oval 1 preamp to amp | Wireworld Eclipse 7 DAC to Preamp | Wireworld eclipse digital IC Oppo to DAC | Audioquest Quartz tuner to preamp |
  • The stove pipe on top of the tuner helps as an antenna... LOL
    Sources: Technics SL1200MKII | SME3009 Tonearm | Monster Alpha 1 MC cartridge | Oppo UDP203 disk player | Nikko NT-790 analog tuner | Musical Fidelity Trivista 21 DAC | Preamp: Threshold SL-10 | Amplifier: Threshold Stasis 2 | Speakers: Snell Acoustics C/V | Kimber 12-TC bi wire speakers | Analysis plus Oval 1 preamp to amp | Wireworld Eclipse 7 DAC to Preamp | Wireworld eclipse digital IC Oppo to DAC | Audioquest Quartz tuner to preamp |
  • mhardy6647
    mhardy6647 Posts: 33,894
    The "OLA" (Original Large Advents) were/are fairly low sensitivity acoustic suspension loudspeakers, although not terribly hard to drive.

    That said, they weren't really designed to be driven by transformer-coupled, vacuum tube amplifiers.
    Are you sure there was enough gain and (preamp) drive to the power amp section of the integrated?
    My guess is that the amp just didn't match too well to the load, or there wasn't enough source signal voltage to drive the whole shootin' match to the desired output. PP EL34 in pentode mode ought to be good for 30 or 35 wpc.

    As a side-point, I tried my (fairly sensitive) Polk Monitor Series Model 7As with my EICO HF-81 (push-pull EL84; ca. 12 wpc) once. Sounded pretty cr@ppy. :(


    Audio
    measured 90 dB SPL for 2V input at a distance of 3 feet. Obviously, that's not the current standard for sensitivity, but it's also not way off (2.83 V at 1 meter for an 8 ohm loudspeaker).

    https://worldradiohistory.com/hd2/IDX-Audio/Archive-Audio-IDX/IDX/70s/Audio-1970-07-OCR-Page-0043.pdf#search="large advent sensitivity"

    9rcyqfnqx72p.png
    see the whole test via
    https://worldradiohistory.com/Archive-All-Audio/Archive-Audio/70s/Audio-1970-07.pdf

    Audio went on to say:
    Efficiency of the Advent speaker is average for an acoustic suspension unit. 6.5 volts into a nominal impedance of 8 ohms, representing 5 watts, was enough to rattle windows with this speaker.
    While a good 25 watt-per -channel amplifier should be sufficient, 50 to 75 watts is not excessive.



  • I tried a couple of sources. A Parasound phono preamp, a CD player and the headphone jack on my cell phone. Similar results from all three sources.
    Sources: Technics SL1200MKII | SME3009 Tonearm | Monster Alpha 1 MC cartridge | Oppo UDP203 disk player | Nikko NT-790 analog tuner | Musical Fidelity Trivista 21 DAC | Preamp: Threshold SL-10 | Amplifier: Threshold Stasis 2 | Speakers: Snell Acoustics C/V | Kimber 12-TC bi wire speakers | Analysis plus Oval 1 preamp to amp | Wireworld Eclipse 7 DAC to Preamp | Wireworld eclipse digital IC Oppo to DAC | Audioquest Quartz tuner to preamp |
  • F1nut
    F1nut Posts: 50,645
    edited September 2022
    I drive a pair of modified Baby Advents with a 22 wpc integrated SS amp. They get plenty loud, not rock concert, but loud enough.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • mhardy6647
    mhardy6647 Posts: 33,894
    edited September 2022
    F1nut wrote: »
    I drive a pair of modified Baby Advents with a 22 wpc integrated SS amp. They get plenty loud, not rock concert, but loud enough.
    ... and the Babys are smaller and (presumably), if anything, somewhat less sensitive than the OLAs.
    Yeah -- if gain's not the issue, I am thinking it's a load/source (mismatch) kind of thing.
    Something like an h/k 330C (20 wpc) or a Marantz 2220B (20 wpc) will work reasonably well with a pair of OLAs, e.g.

    They were really never meant for vacuum tube amplification. :|
  • mhardy6647
    mhardy6647 Posts: 33,894
    Baby Advent II (way post-Kloss... Recoton era, if memory serves?)

    24564116830_9f96de403f_b.jpg
  • F1nut
    F1nut Posts: 50,645
    rkiht0wy0iqf.jpg
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • Nice! I had a pair of mini Advent speakers. Had to refoam them a while ago and then gave them to my son for his dorm room.
    Sources: Technics SL1200MKII | SME3009 Tonearm | Monster Alpha 1 MC cartridge | Oppo UDP203 disk player | Nikko NT-790 analog tuner | Musical Fidelity Trivista 21 DAC | Preamp: Threshold SL-10 | Amplifier: Threshold Stasis 2 | Speakers: Snell Acoustics C/V | Kimber 12-TC bi wire speakers | Analysis plus Oval 1 preamp to amp | Wireworld Eclipse 7 DAC to Preamp | Wireworld eclipse digital IC Oppo to DAC | Audioquest Quartz tuner to preamp |
  • K_M
    K_M Posts: 1,629
    newbie308 wrote: »
    I'm at my friend's hunting cabin this weekend. I thought it would be fun to bring a EL34 integrated amp with me as an "upgrade" to the 1980's Panasonic baby blue all in one stereo he's been using there since we were kids. To my surprise, the EL34 amp won't drive the speakers well at all. I had to crank the volume knob to 80% of full volume to hear anything so, I'm guessing that the speakers are power hungry? Reconnected the baby blue Panasonic and they play fine.

    Are you saying LITERALLY you can hear almost no sound until at 80% volume level?

    Or that they just do not get "Loud"??

    They are not that power hungry of a speaker really, and if anything your integrated should be easily able to play them somewhat loudly.

    Connection issue or something else maybe?
  • mhardy6647
    mhardy6647 Posts: 33,894
    F1nut wrote: »
    rkiht0wy0iqf.jpg

    Yeah, those are the real ones, with a Kloss-y tweeter :)
    I only ever had the much later II morph -- just felt like sharin' an image (irrelevant though it be), although it unfortunately gives no sense of scale. They Babys are... quite small. :|

  • gp4jesus
    gp4jesus Posts: 1,988
    Just spit ballin’. Impedance mismatch?
    Samsung 60" UN60ES6100 LED, Outlaw Audio 976 Pre/Pro Samsung BDP, Amazon Firestick, Phillips CD Changer Canare 14 ga - LCR tweeters inside*; Ctr Ch outside BJC 10 ga: LCR mids “Foamed & Plugged**”, inside* & out
    8 ga Powerline: LR woofers, inside* & out
    *soldered **Rob the Man (Xschop) LR: Tri-amped RTi A7 w/Rotels. Woofers - 980BX; Tweets & Mids - 981, connected w/Monoprice Premiere ICs
    Ctr Ch: Rotel RB981 -> Bi-amped CSi A6 Surrounds: Premiere ICs ->Rotel 981 -> AR 12 ga -> RTi A3. 5 Subs: Sunfire True SW Signature -> LFE & Ctr Ch; 4 Audio Pro Evidence @ the “Corners”. Power Conditioning & Distribution: 4 dedicated 20A feeds; APC H15; 5 Furman Miniport 20s
  • mhardy6647
    mhardy6647 Posts: 33,894
    gp4jesus wrote: »
    Just spit ballin’. Impedance mismatch?

    I'm guessin' no, FWIW.
    ... but it's (just) a SWAG.

    :|
  • gp4jesus wrote: »
    Just spit ballin’. Impedance mismatch?

    No, I checked that. The speakers are 8 Ohm and I was connected to the 8 Ohm Jack and common of the amplifier.
    Sources: Technics SL1200MKII | SME3009 Tonearm | Monster Alpha 1 MC cartridge | Oppo UDP203 disk player | Nikko NT-790 analog tuner | Musical Fidelity Trivista 21 DAC | Preamp: Threshold SL-10 | Amplifier: Threshold Stasis 2 | Speakers: Snell Acoustics C/V | Kimber 12-TC bi wire speakers | Analysis plus Oval 1 preamp to amp | Wireworld Eclipse 7 DAC to Preamp | Wireworld eclipse digital IC Oppo to DAC | Audioquest Quartz tuner to preamp |
  • I'll just throw this out. Is it possible that in transit one or more of the tubes got jostled and aren't making good connection? Maybe remove them all and clean the pins with contact cleaner and reseat?
    George / NJ

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