Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

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markjazzbassist
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Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

Post by markjazzbassist » Mon Dec 06, 2021 2:04 pm

As many know i am a cassette enthusiast, and have spent a lot of free time at work reading manuals on various recorders. Something that really has stood out is my study of the Tascam 238, i owned one and something that made it unique is the Bias is set at 35us which is what 15IPS reel to reel machines are set to in Europe (CCIR). I've done some reading and research and many claim this is one of the contributing factors to why it sounds so good, flatter frequency response (less boost, less hiss) and smoother bass and low mids.

Well i found in the 246 manual today that it also uses the 35us bias. I didn't know that, and searches on the interwebs didn't yield anything so you are hearing it here first.

Every other 4/6/8 track portastudio or syncassette by tascam or fostex or others is set to 70us for CrO2 tapes. The 246/238 are the only machines that use that 35us bias. Very interesting indeed, many do regard the 246 as the best portastudio, and the S/N specs are 4-5db better than 244/234/etc so me thinks this 35us might play a part since they are similar year/make/parts.

not sure if anyone cares, but wanted to share anyways

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Re: Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

Post by shedshrine » Tue Dec 07, 2021 10:12 am

Interesting! Had not been aware of that, thanks!
________________________________

"Hello, MultiTrack Recorder Repair and Restoration, How may I help you?"

"Hi, I read that the Tascam 246 and 238 are biased at 35us like 15" open reel tape,
rather than 70us like on the Tascam 424 series and such. Can you mod my 424 to 35us?"

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Re: Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

Post by floid » Wed Dec 08, 2021 1:42 am

Makes sense, these units run double speed so the eq is double the freq.
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Re: Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

Post by shedshrine » Wed Dec 08, 2021 8:54 am

Tascam 424 mkII.JPG
Tascam 424 mkII.JPG (35.81 KiB) Viewed 11289 times
Tascam 238.JPG
Tascam 238.JPG (42.2 KiB) Viewed 11289 times
having cereal at my desk,
catching up with Floid and MarkJazz Bass-est.
Looking for granules of insight,
from manuals on the website,
424 vs 238
both go 9.5 but wait,
the 424 goes three and three quarters,
the 238 three and a half, why the disorder?
Regardless of this state,
35us for both would be great.

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markjazzbassist
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Re: Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

Post by markjazzbassist » Wed Dec 08, 2021 9:39 am

strange i never caught that, i'm not sure if that's a typo or something that sets it apart.


FLoid most multitrackers run double speed, that's not anything to note really. 99% of cassette multi-trackers (that are double speed) that use Type II CrO2 tape are 70us bias though, and the fact that the 246 and 238 are 35us bias is something to note, which was the point of my original post.

The prices on the 246 have gotten outrageous so sadly i won't be purchasing one of those. my studio is very small so my 238 and mixer (sound workshop 1280) had to go as well, part of the cost of moving to a smaller house.

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Re: Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

Post by shedshrine » Wed Dec 08, 2021 10:01 am

Mark,
So what are you using to record with these days?
How's it working for you?
Is your bass on a stand too close to a door like in Janek Gwizdala's room? ; )

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markjazzbassist
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Re: Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

Post by markjazzbassist » Wed Dec 08, 2021 10:55 am

shedshrine wrote:
Wed Dec 08, 2021 10:01 am
Mark,
So what are you using to record with these days?
How's it working for you?
Is your bass on a stand too close to a door like in Janek Gwizdala's room? ; )
i have a Fostex 250 i've been using, there are Direct In's which bypass any mixer circuitry and go straight to the tape, i use outboard preamps with those. it works alright but i'm having transport issues so i'm gonna have to offload it. i'm in the process of getting my Teac 144 fixed as well or finding a refurbed one, something about me is really interested in using the very first porta made and trying to make it work. i find my workflow is better with 4 tracks, when i used 8 trackers i just threw stuff down with the "i'll mix/fix it later" and then i never do that (i really don't like mixing). i am so lazy/apathetic that the "i'll fix it later" included the arrangement (yeah i thought i would mute stuff strategically, yep never happened). the 4 track i plan and get stuff printed as it should sound because i have to (reverb and effects included) which makes mixing a task of just adjusting levels and pan. basically i hacked my process to overcome my personal laziness/apathy. also i moved to a smaller house so the big mixer/rack cassette just took up too much space. i like small and minimal, less is more. i'm more inspired to break boundaries and make the most with the least, when i'm given lots i'm just un-inspired and feel overwhelmed. lastly i am not a DBX fan, so the fostex and teac have dolby which is acceptable, or i just go no NR and cut at 4k like 3db and it's fine.

lol on the bass stand, no i use the wall hooks to mount on the walls and they are no where near doorways :)

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Re: Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

Post by floid » Wed Dec 08, 2021 12:36 pm

markjazzbassist wrote:
Wed Dec 08, 2021 9:39 am

FLoid most multitrackers run double speed, that's not anything to note really. 99% of cassette multi-trackers (that are double speed) that use Type II CrO2 tape are 70us bias though, and the fact that the 246 and 238 are 35us bias is something to note, which was the point of my original post.
CCIR/IEC high frequency eq varies according to tape speed though, right? 70us @7.5ips, 35us @15ips.
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Re: Interesting Tascam Cassette Bias Observation 35us vs. 70us for 238 and 246

Post by shedshrine » Wed Dec 08, 2021 12:56 pm


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