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High pass filter with my ancient amps

Discussion in 'Amps and Cabs [BG]' started by webmonster, Feb 22, 2014.

  1. webmonster


    May 19, 2013
    New Zealand
    I like old-school rigs. I have two TL-606 cabs and three vintage valve amps to choose from, ranging from 50 to 200 watts.

    I've read several threads on TB about using a HPF device can increase headroom because the amp isn't wasting power dealing with very low frequencies - sounds like a good thing!

    Do HPF devices work best placed before an amp's input or in the effects loop? (two of my amps have an effects loop, presumably after the tone stack)

    If I squint really hard at my copy of a copy of the TL-606 plans it looks like the cab starts rolling off at about 70Hz; would this be a good freq. initially to set a HPF for my rig? (once I get hold of one)
  2. lowphatbass

    lowphatbass **** Supporting Member

    Feb 25, 2005
    west coast
    What are the ancient amps you own that have effect loops?
  3. You might also increase clean headroom in the preamp by preceding it with the HPF. Otherwise it doesn't much matter. The main advantages are clean lows and less blown up speakers, until you take it too far with a big solid state amp and overheating becomes the failure mode.
  4. webmonster


    May 19, 2013
    New Zealand
    The Selmer T'n'B 50SV (early 1970s) has a factory installed Echo send/return on the front panel and my Jansen Bassman (c.1967-68) has had an Echo send/return installed by someone on the back panel.
  5. webmonster


    May 19, 2013
    New Zealand
    I see what you mean. That could be useful.
    I've got one solid state amp - a mosfet custom built thing rated somewhere between 300 and 500W @ 4ohms depending on who built it and who measured it. However, it's not on active service at the moment...

    What are you using for HPF duties?
  6. Boot Soul

    Boot Soul

    Feb 10, 2009
    Those old Selmer Treble 'n Bass 50 SV and 100 SV sound great with bass. I have been looking out for one of them but they don't show up in the US very often.

    I like the tone of this amp driven a little by a SansAmp >
  7. Hi.

    Those threads mainly deal with SS amps.

    On a tube amp, the OT acts as a HPF, so the benefits are not as pronounced.

    On a SS amp the effect can be rather astonishing.

    No harm in trying though.

  8. FerK

    FerK Supporting Member

    Dec 11, 2011
  9. Trace amp has eq down to 30hz.

    Otherwise, I have taken to using my Rolls mini crossover which goes down to 50hz, taking the highs only.
  10. webmonster


    May 19, 2013
    New Zealand
    Hmmm! So more effective with SS stuff.

    The Jansens both seem to have rather low centres (Q?) for the bass tone controls. This must eat into their headroom at higher volumes so any further control I can have would be handy to try out.
  11. webmonster


    May 19, 2013
    New Zealand
    I agree - it does sound great for bass :)
    I also agree that they don't come up often where I live - NZ. Mine must have been a personal import by someone who came out from the UK. NZ had very strict import restrictions until the 1980's.