Ultra Flanger vs Vintage Electric Mistress

[lonewolf]

I recently built the john hollis ultra flanger and was comparing it to my 33 year old electric mistress..the hollis flanger has more sweep,etc but the electro harmonix has more clarity/punch/frequency response..would the ultra flanger sound better if the voltage was bumped up from 9.6 volts to around 18 volts?

[Scruffie]

Assuming you used the 3007 in the Ultra Flanger, the max voltage is 15V ,so use a LT1054 voltage doubler + regulator if you don't have an 15V Supply or just 18V plus the 15V regulator, 3207 are 10V max (8V2 works best IME).

The ultra flanger is a severely stripped down flanger, the clarity will probably be coming from the electric mistress due to better low pass filtering and more reliable biasing (can't remember the Ultra flanger exactly but if it's anything like the Zombie chorus, the biasing isn't the best for avoiding distortion, just there to make it work and be easy).

You might have better luck building an Ultra Flanger with the same LFO/Clock/Delay time set up for the same sweep but the Electric Mistresses audio path for the clarity... run at 15V or 9V.

[hannibal827]

I recently built the john hollis ultra flanger and was comparing it to my 33 year old electric mistress..the hollis flanger has more sweep,etc but the electro harmonix has more clarity/punch/frequency response..would the ultra flanger sound better if the voltage was bumped up from 9.6 volts to around 18 volts?

I'm not 100% sure, but I think I might have actually tried +15v when breadboarding my Ultra Flanger, and it didn't make much difference.

the clarity will probably be coming from the electric mistress due to better low pass filtering and more reliable biasing (can't remember the Ultra flanger exactly but if it's anything like the Zombie chorus, the biasing isn't the best for avoiding distortion, just there to make it work and be easy).

The filtering on the Ultra Flanger is really minimal, which is the stated goal of the design, so just about any commercial flanger is going to have a more complicated, and probably better filtering network, whether it's LPF or pre- and de-emphasis.  I have tried both biasing schemes in the Ultra Flanger: the resistive divider and the added trimmer in R.G. Keen's .pdf.  I got a working bias with just the fixed resistors, and didn't hear much audible difference "dialing in" a bias with the trimmer, so I wound up leaving the trimmer out.  That said, I don't get distortion in my Ultra Flanger.  I know there's a YouTube video of someone's UF, and it does distort, but the person who posted the video says that he modded the circuit, so...

Back to the supply voltage: I have been playing around with an Ibanez FL-301 circuit on my breadboard, which is an older, 12-volt version of the 9-volt FL9 from the 1980s [the FL9 also exists as a current reissue].  Predictably, the two circuits are really similar.  So, I wondered, does the FL-301 really need 12 volts, and why?  Running it on 9 volts, I could avoid distortion if I strummed really softly, but anything louder than that produced some ugly clipping.  The reason for this, I think, it how each circuit handles pre-emphasis and de-emphasis.  The FL9, the 9-volt circuit, boosts the treble at about a 6:1 ratio before the signal hits the BBD.  The FL-301, the 12-volt circuit, boosts at a ratio of about 11:1.  I'm guessing that the extra boost causes the clipping at a reduced voltage.

So--I think--the only advantage of increasing the Ultra Flanger's voltage would be to accommodate a more sophisticated filtering network, one that boosted treble enough to produce clipping at 9v, and of course de-emphasized enough post-BBD to give more "clarity."  But...

The ultra flanger is a severely stripped down flanger,

...and I'm finding that while I like it well enough, and feel like I learned a lot from building it, there are existing flanger circuits out there that already incorporate the little things the Ultra Flanger needs to be "better."