So you may have read about the lineage of this unit. It's based on the console preamps and EQs from the console at Olympic Studios where some of the most iconic 70's rock albums were recorded. It's been described by others as "woody" and a unique flavor between API and Neve. Intrigued by the descriptions, I decided to try one out.
When I first used this box, I was trying to add some outboard EQ to a lackluster distorted rhythm guitar track. It was kind of harsh in the mids, but lacked in body and needed some muscle and some smoothing. I ran the tracks out of my DAW and into the Helios with the gain switch set to "Line" and added a little 1.4 kHz with the mid control. My co-engineer and I heard the resulting sound coming out of our speakers, turned to each other and said, "Holy crap that sounds just like. . . " "Pete Townsend, yeah, it's crazy." Since then we've use the Helios as outboard EQ to mix Kick drum, snare, bass, vocals, as well as using the preamp to mic acoustic guitars, electric guitars.
Overall, I would have to say that the description of the tone of this unit as "woody" is pretty accurate. On guitars, it's definitely got that Who/Pink Floyd smooth mids without sounding scooped or dull. On snare and kick it accentuates the shell of the drum and smooths out transients in a very pleasant, vintage-sounding way. I have to say that everyone at our studio freakin' loves the sound of this thing, from the interns up to the senior staff. We do a lot of nostalgic folk rock stuff, and I wish we could afford a whole rack of these babies.
For features, in additional to the great sounding pre, there's a switchable low cut filter (40 Hz or 80Hz), phantom power and phase reverse. There's a nice smooth sounding High Shelf @ 10kHz in 2 dB increments that helps add or cut some top end when you need it. The other EQ bands are different than anything else you've probably used. There's a Mid and Bass band and a peak/trough switch that determines whether the bands boost or cut. The mid and bass bands both have continuously variable gain or cut at selectable fixed frequencies. I overall pretty happy with the number of frequency selections, the options are generally enough to get the band you need. The bass band also has a selectable filter below 70 Hz where you dial in progressively deeper cuts (from -3dB down to -15dB). It's a little redundant with the low cut filter at 80Hz, but what the heck, it's on the original and maybe someone has a use for it.
So because this is a review, I have to have some negative things to say. My biggest gripe may seem trivial, but here goes: The labeling is unclear and there is no manual. In fact, the closest thing to a manual is for the UAD plug-in version. Most importantly, there is no label or LED to indicate whether the phantom power is engaged or not. It's really easy to have the phantom power on and not know it. I had to really hunt for the answer to this, but the Up position is Off based on the British lightswitch standard, which is opposite from the US lightswitch standard. Considering my love for Ribbons and the fact that if you use the EQ as outboard during mixing you could easily send +48V back up into the outputs of your converters, I was irked that they couldn't just put a silk-screened "Off" on the face.
Another option that I wish I could have on this unit is the ability to cut or boost the bass and mid independently. Sometimes you want to cut 240 Hz while boosting 2kHz, but with this unit you have to pick one of the other.
Finally, the unit has relatively low headroom and output compared to a lot of modern preamps. It's really easy to clip this thing with the output of a DAW, even when operating in line input mode. As a mic pre, it's usually got enough juice, but sometimes we have needed to follow up the unit with an extra gain stage if we were sending things out to our passive summing bus for a mix down. Combined with the eccentric labeling and lack of manual, the low headroom causes this box to have a more of a learning curve than a lot of similar units. Fortunately, it's hard to get a bad sound out of this thing as long as you're not clipping.
At a street price of $1500, the Helios Type 69-500 is a little steep compared to most 500 series pres, but to us it's well worth the price to have such a cool preamp/EQ combo. Among our Daking, API, Shadow Hills, Sytek, and Ampex preamps, this has fast become one of our most frequently used players, and a first choice for rhythm electric guitars and snare.
I recently picked up a pair of these 500 series modules. So my experience so far is limited.
My first application for the Helios pair was mic'ing a pair of guitar amps for chunky rhythm guitars. I used 2 SM7B mics up close on a Mesa Solo Rec / sealed 4X12" Mesa Cab with Vintage 30s and an Orange AD30TC combo with 2X12" Vintage 30s. We needed to energize a big chorus on a pop-rock tune with the prototypical power chords. The amps were out in our live room, seperated from each other by a rolling Real Traps gobo. The guitar was a Les Paul (of course), but nothing fancy. We used a Little Labs STD guitar extender to allow the guitar player to sit with me in the Control Room. The Little Labs box has dual outputs, and we often use it to run two amps together.
The client started his palm-muted build up to the chorus, then let the sustained chord rip. He got really happy. He is a trained studio engineer in his own right, but remarked that he had never achieved a tone anything like that before. This setup just sounded great. The tone was solid, without ever sounding tubby. You could turn up these heavy guitar tracks a bunch before clouding up the mix.
Neve and API are different and both very useful, but the Helios is different from both. It does not seem to do the coloration thing that Neves do and APIs do a bit when running hot. The Helios' output is noticeably lower as well. If you like to print hot, you might want to use some make up gain after the Helios. On one occasion in recording this guitar amp combination, I used our VacRac TSL-4 for make up gain and a touch of limiting. It was nice, but I wouldn't hesitate to use an 1176, or any other decent compressor for make up.
Using the HF cut / boost at 10k can give you a range of tones from airy to dark. Despite the radical boosting you can do in the high end, you would have difficulty making it sound harsh. Rolling off some top end yields a smooth, dark tone that still sits well in most any mix. The mid range controls (peak/trough) also gave us a lot of frequency options. There is even a non-original 16k selection in the mid range EQ. I don't know how much I would use the 16k, but somewhere down the line, who knows. The mid range controls gave a variety of tones, none of which sounded bad. Some people gravitate toward certain frequencies, according to online posts. But I find most all the frequency selections useful.
I never found myself using this EQ correctively. It was always more about getting a sound I liked, and the Helios can make it hard to decide what you like best. Turning knobs just makes it different, not so much better or worse. I mean that in the most positive way.
It is a great alternative to Neve and API. We have a bunch of vintage 31102s and a couple of the newer 1073LBs. We also have a bunch of API 312/3124 pres and a few 550B EQs. API and Neve are different from each other in a complementary way, but the Helios is entirely different sounding than both. Closer overall to an API on the preamp side of things, it is still not the same. The low end is more subdued on the Helios pre.
I also find the HPFs at 40 and 80Hz make more of a difference than I would have thought. I would use the HPF on this unit less than I would on the 31102s, our Chandler LTD1, or our SSL console. The filters just do too much for how I have used it so far. almost like a gently sloped 80Hz and 125Hz instead of 40/80. But again, that is only with my limited experience recording electric and acoustic guitar. I haven't used them for anything else yet.
I have read that these EQs are great for mixing snare, guitars, and bass. I can see that. The low end EQ has been compared to Pultec EQs. I really do want to try the LF control when mixing bass guitar and kick.
Minor gripes would include:
1. The HPF @ 40 and 80 Hz makes more of a difference than I expected. Perhaps on other sources, I will find the HPF more useful.
2. Also, as noted in the other review, the upside-downness of British switches and lack of clear labelling on the 48v could be a bad deal for ribbon users, or anyone who unintentionally hot patches a line with phantom active.
3. Of the two units I received, one had an issue with condensers. When I would hook up a condenser or active ribbon, the Helios would not pass any mic signal, but would produce a low hum. This happened whether phantom was off or on. After reporting the issue to the dealer, I am confident they will provide a replacement, but it seems like they are reluctant to resolve this issue as quickly as I would like. I don't get a sense that these are poorly made at all. Some of my best handwired gear initially came to me with problems. But they were fixed quickly and have given me many trouble free years of operation. The real drag is that I now feel like I NEED to have both these units in good working order, not just the one, AND NOW. They are quickly becoming go to units, even though I have lots of good Neve, API, Chandler, A Designs, and other units around. So I am losing patience for a fully operational replacement to show up.
4. Price is a bit steep.
This is a very good mic pre and fantastic EQ in a single space, lunchbox form. Is there another 500 series unit that offers that much functionality? AML has the 1073ez-500 with Neve-ish pre and EQ, in two spaces, at a good price. AML makes good stuff - definitely worth a look. But the Helios is different from so many API-ish and Neve-ish units, and is more rare, at least for now. I have two, but want more. At 1550 USD a piece, I think it is a worthwhile investment to have a few.