Driver and cabinet advise for low wattage tube amp

srw

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Joined 2023
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Hi all,

Lurker turned first-poster. I'd like to make a pair of speakers to be driven by a low wattage tube amp but im lost in this sea of information and would like to ask the forum here for some guidance on a driver selection and a suitable cabinet type/plan.

Here are some requirements/preferences i have
  • full range driver
  • drivable by 2 watt tube amp
  • 11ft x 12 ft room, placement will be have to be near a wall
  • Only need medium volumes, up to say 80ish dB?
  • I listen to lots of music types so preference toward generalist over specialist in terms of genre suitability
  • I accept that I wont get low lows and high highs out of this, but would enjoy mid-bass presence.
  • preference for clarity and dynamics over, say, deep bass or big sound stage.
  • prefer tower over bookshelf cabinet
  • cabinet complexity is not a concern, am a capable wood worker with a shop.
  • driver cost up to around $500 but less is also great :) other material costs not an issue for me.
  • in USA if that affects sourcing or anything else
I hope this isnt a silly wish list, but even if you need to toss a bullet or two id still very much appreciate any suggestions that youre willing to give
 
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srw

Member
Joined 2023
Paid Member
thanks! The amp in question is a decware zen triode se84ufo2. I dont see its output impedance given on the spec sheet. It does have a high/low impedance switch that I saw are nominally to 8 or 4 ohm speakers, but that's all I got sorry :/
 
frugal-phile™
Joined 2001
Paid Member
[*]drivable by 2 watt tube amp

Which one? Output impedance?

[*]11ft x 12 ft room, placement will be have to be near a wall
[*] Only need medium volumes, up to say 80ish dB?

Small room, low levels, Power is unlikely to be an issue. Flat impedance response is more important likely.

[*]I accept that I wont get low lows and high highs out of this, but would enjoy mid-bass presence.

Why?

[*]prefer tower over bookshelf cabinet

Sealed, TL, or horn then.

Alpair 10p in Pensil? FHXL? Really decebt bass, glorious midrange, vintage top (tame and perhaps a bit rolled off). Also fairly sensitive, 2 w will give 93 dB peaks before compression. And fairly easily tweaked for even better performance.

I have not heard CHP-90, it gets good reviews. A little smaller, less sensitive, same DNA. Generally it goes CHN/CH(Por R)/Pluvia/Alpair was the increasingly better product lines but that has been thrown into chaos with many or the latest products.

dave
 
Last edited:
Seas FA22RCZ

Around 94dB efficiency, so 2W is enough for normal listening level in your room size.
I have them in my current speakers. My room is 12x16 ft. and placement is against longer wall. Listening levels also up to 80dB.
They work really good with all kind of music. Hard&Heavy, Disco, 90's electronic, Classical, etc.
I would describe the sound as modern, open and clean. Both LF and HF extension are really good. Sub or tweeter are not necessary. Tonal balance is on the bright side but HF are easy to control by slight off-axis listening (10deg toe-out in my case). Iam not using any kind of response correction. Soundstage is a bit smaller compared to my previous 2,5way speakers but really a negligible difference.
In short, they do everything right.

For cabinet, Seas recommends 60 liter sealed box. That gives F3 around 60Hz with 12dB/oct rolloff, so bass response is good all the way to 40Hz.
 
frugal-phile™
Joined 2001
Paid Member
Seas FA22RCZ

Surprisingly i haven’t measured my pair, but i doubt they are 94 dB sensitive.

Good but they need phase plugs. http://www.planet10-hifi.com/downloads/B200-phase-plug.pdf The base needs notching to accomodate the 2 “bumps” in the pole piece.

A simple sealed enclosure works well, mine are a bit less than the 60 litres recommended. Sealed is flexible.

Scott has a few more exotic enclosures: https://www.diyaudio.com/community/...-mark-audio-fostex-tb-dayton-seas-etc.323051/

dave