Help Assessing Fostex R8 Heads! (Need your two cents)

sammcdougallIV

New member
Hey all - I'm considering buying this R8. I've owned a few before and always regretted letting them go:facepalm:. Excited to have an opportunity to get another one, but I'd like some opinions on the condition of the heads here. Obviously pictures never do the reality justice - but if you had to make a judgement, what would it be?

Thanks and I really appreciate any input!fostexhead.jpgfostexhead2.jpg
 
Thing is - It's being shipped to me so I can't run tape through. I trust the guy and he's demo'd the transport to my satisfaction and the machine is otherwise clean - just wondering about the life of these heads as that'll be the deal-deciding factor for me.
 
When I had the head lapped on one long ago I was told 'we'd get one lap and that the heads metal wasn't particularly hard 'as heads go I guess.
So take all this with a grain of salt-- They look worn, but I can't tell from the photos.
Have they been done before?
 
So you are right...you can't really know anything for sure from a picture...you really can't even know anything for sure looking at a headstack with the naked eye.

What I *can* tell you is the assembly looks clean, there is no keystoning or hourglass wear pattern to the face of the record/play stack, the lifters appear to have no more than nominal wear, and what wear i can see on the guides corroborates with what I see on the lifters, though guides can typically be rotated...lifters are much harder if not impossible to rotate, so I use their condition to reinforce what I'm seeing with other aspects.

Overall it *appears* to be a well-maintained tape path with no more than average miles.

Take my opinion with a grain of salt, please, because it's formulated using nothing but two pictures. But if I was in the market for an R8 I'm not seeing anything that would prompt me to keep walking.

But the ONLY way to know if the condition is okay is to align the machine and see if the specified frequency response can be achieved, and the ONLY way to know the wear percentage is to have the assembly analyzed and evaluated by somebody like John French.
 
Thanks sweetbeats, that's really helpful information and I'll use it with a grain of salt as you suggested.
I don't want to wear out my advice-welcome - but here's another contender to make it an either / or decision. Details to keep in mind - this one is obviously dirtier - but it's also a good deal cheaper.

IMG_0789.JPGIMG_0794.JPG
 
Unfortunately I can't constructively comment on that second machine...the seller would *have* to clean the sticky shed off the heads and guides and retake the pictures with better light and focus.

If it were me I'd walk away just based on the fact the seller has not maintained the machine and didn't take care of basic tasks to send you pictures that tell you anything.

If the price is stupid low then maybe buy it with the idea it is a parts machine and maybe you get lucky and it is fully functional once cleaned up, but I wouldn't buy it settled on the idea it is 100%. That make sense?

What are the sellers asking for these machines?

The first machine, at least by looking at the headblock assembly, appears lovingly maintained.
 
Unfortunately I can't constructively comment on that second machine...the seller would *have* to clean the sticky shed off the heads and guides and retake the pictures with better light and focus.

If it were me I'd walk away just based on the fact the seller has not maintained the machine and didn't take care of basic tasks to send you pictures that tell you anything.

If the price is stupid low then maybe buy it with the idea it is a parts machine and maybe you get lucky and it is fully functional once cleaned up, but I wouldn't buy it settled on the idea it is 100%. That make sense?

What are the sellers asking for these machines?

The first machine, at least by looking at the headblock assembly, appears lovingly maintained.

350 for the clean looking one - 250 for the dirty one.
 
That's a no brainer IMO. The disparity of the clean condition of $350 machine (and video verifying transport functions) compared to the neglected state of $250 is worth more than $100. $350 seems like a very reasonable price.
 
Pulled the trigger on the machine with the cleaner headblock!
Fingers crossed I've nabbed a good one with plenty of tread left.
Here's another photo, will post updates when I receive the machine!
Thanks again for the help.fostexgen.jpg
 
You bet!

Keep us posted. Hope the seller knows how to pack the unit for safe travel. There is a great "sticky" thread at the top of the forum on this subject in case you haven't seen it. Often buyers will refer sellers to this thread to help guide proper packing.

Your new R8 looks to be in good shape according to the pictures.

Something to keep in mind about head wear...it takes a lot of hours to wear heads down to the point a relap is needed or the heads are entirely beyond the service limit. Steve Puntolillo of Sonicraft A2DX Labs gave me some perspective on this during a conversation some years ago. Steve has a flock of machines in his operation that are frequently to constantly running. Check out his webpage Sonicraft A2DX Lab: Ultimate Multitrack Reel to Reel Analog to Digital Transfers. He shared an anecdote regarding one of his Ampex MM-1200 machines that was usually running the majority of the hours in a 24 hour day and 6-7 days per week, and after a year or more of this and seeing the headstacks were visually worn, he sent them to JRF Magnetic Sciences for analysis. Steve expected bad news...he was anticipating the head report would show one or both of the stacks could not be relapped and needed replaced. The head report came back and there was still 50-75% remaining. How often are you planning on running the R8? For many, or maybe even a majority of us on this forum, it is periodic recreational use. Steve asked me about my utilization of my MM-1000 as we discussed a 1" 8-track headblock assembly I'd just gotten back from being assessed and setup by JRF where it was deemed to be about as close to "new" as you could get. When I answered Steve's question about my typical utilization of the machine (periodic recreational use as opposed to full time professional use) he said my 1" assembly should last a lifetime. He really put me at ease, and I consider him to be a true subject matter expert. Now, your situation may be different, and the R8 and an MM-1000 are not the same machine, but your new-to-you machine really does appear to have had average to below average use and to have been cared for and maintained. Depending on how much you will be using it, I expect the existing record/play head will last you many, many years. Make sure you are using the correct tape type for the machine, and if at all possible ensure the tape tensions are correctly set...these things will prolong the life of the tape path components.

Enjoy the machine, and do keep us posted!
 
I have a huge soft spot for these machines though I have moved on to (somewhat) higher-fidelity stuff.
As far as sound quality goes they blow the 388 out of the water. Wish the transport was as nice.
I'd highly recommend sending the head block to John French before you attempt tweaking any of the record calibration trims. On the majority of these prosumer 2-head kind of machines I have worked on, nobody ever tweaked anything and the freq response is nearly perfect upon installing the relapped headblock. (This happens often enough that it's now shop policy to decline calibration on any 2-head machine with a significant degree of head wear.)
Caveat wrt removing headblock from an A-8, 80, R8 etc for maintenance: You must unsolder all 32 head leads, they don't unplug like most headblocks. Take detailed notes/pictures. The wires are in the normal resistor color code order IIRC.
 
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I have a huge soft spot for these machines though I have moved on to (somewhat) higher-fidelity stuff.
As far as sound quality goes they blow the 388 out of the water. Wish the transport was as nice.
I'd highly recommend sending the head block to John French before you attempt tweaking any of the record calibration trims. On the majority of these prosumer 2-head kind of machines I have worked on, nobody ever tweaked anything and the freq response is nearly perfect upon installing the relapped headblock. (This happens often enough that it's now shop policy to decline calibration on any 2-head machine with a significant degree of head wear.)
Caveat wrt removing headblock from an A-8, 80, R8 etc for maintenance: You must unsolder all 32 head leads, they don't unplug like most headblocks. Take detailed notes/pictures. The wires are in the normal resistor color code order IIRC.

Thanks for the advice - I'll consider that for sure and likely make a decision based on the results of testing everything out once I get the R8 (I'll be grabbing it from my US address in Michigan this Saturday).

Though I'm wondering - have you gotten the heads re-lapped on an R8 before? What is the pricing like? I'm on a student budget so it's a big factor.

If I get the opportunity, I'm going to try to pick up a parts machine in January or just a backup if I can at a reasonable price. Not sure if you guys have seen the prices of these skyrocket literally just over the past year.
 
You should contact JRF for pricing. Just give them a call. I *think* the relap and setup on a 1/4" 8-track 2-head block might be $250-300USD?

Sounds like a lot, and I understand tight budgets, but eventually it's part of the cost of one of these machines, and JRF does it right. You get the assembly back precision lapped, optically aligned...good or better than factory. Another option is to send it for an evaluation and I think that's around $75 and you know exactly what you have...but...don't assume it needs that now is my advice. Pdmillar has very sound information you should pay attention to, but consider frequency response will and does change as the head wears and that's what those trimmers are there for, in part.
 
OK. So I got the R8 today. Unboxed it and set it all up. Gave the heads and tape path a cleaning. Testing was going swell until... Track 4. Every track records and reproduces excellently (super quiet and accurate) but track 4 does absolutely nothing. Here's what I've deduced:

1) it's probably not the head track itself? All the tracks sound great - no bleed, no HF loss that I can hear, and no visible reason why track 4 on the head would cause trouble.

2) it's not the rca input or output, for track 4 they're both working great.

3) the remote has a frayed wire near the remote side of the connector cable..

4) most interestingly - when I opened it up, around back where the record cards are connected to their PCB, track 4 was marked with a marker for some reason? Is this a soldering issue? Here's a picture. Any info or advice on a potential solution would be greatly appreciated, otherwise I might just have an R7.20171009_163907.jpg
 
One useful trick for cases like this is to record something on all the tracks and then flip the tape upside-down. When you play it back, track 4 on the head will be playing back material recorded by track 5, and vice-versa.
If track 4 plays back under those conditions, and track 5 is silent, we know that the head itself is good, that the repro amp is working and it's something iffy with the recording amp on channel 4.
Conversely, if Track 5 plays back material previously recorded by track 4, but track 4 is silent, we know that the record amp on channel 4 is working but the repro amp is not.

If both tracks 4 and 5 are silent, that means that channel 4 can neither record nor play back. Which likely means that the connection to the head has failed somewhere (or the head itself is open-circuit but hopefully that's not the case). In that situation it would be a good idea to swap the channel cards around and see if the fault moves with the channel card. Assuming they are not soldered in on the R8, of course. If they are socketed it might even be the case that they just need re-seating.
 
One useful trick for cases like this is to record something on all the tracks and then flip the tape upside-down. When you play it back, track 4 on the head will be playing back material recorded by track 5, and vice-versa.
If track 4 plays back under those conditions, and track 5 is silent, we know that the head itself is good, that the repro amp is working and it's something iffy with the recording amp on channel 4.
Conversely, if Track 5 plays back material previously recorded by track 4, but track 4 is silent, we know that the record amp on channel 4 is working but the repro amp is not.

If both tracks 4 and 5 are silent, that means that channel 4 can neither record nor play back. Which likely means that the connection to the head has failed somewhere (or the head itself is open-circuit but hopefully that's not the case). In that situation it would be a good idea to swap the channel cards around and see if the fault moves with the channel card. Assuming they are not soldered in on the R8, of course. If they are socketed it might even be the case that they just need re-seating.

Ok. I didn't have time to fully remove the channel cards, but I did briefly check to see if it wasn't in place. It seems like it is but a closer / slower look might reveal otherwise.

I'll give the technique you mentioned a try tonight and report my findings with more pictures. I want to get to the bottom of this because I have a hunch it's a solvable problem.

I feel like the connection to the head has failed somewhere - but I don't know where / how to check that thoroughly.
 
I'm pretty sure that it has to do with a record card or a PCB track. Going to swap some cards and see if the fault moves with the card or is tied to the track.
In that case - I don't know where to look for broken connections. Doesn't seem like it would be the head... but I'm not sure.:facepalm:
 
If both tracks 4 and 5 are silent, that means that channel 4 can neither record nor play back. Which likely means that the connection to the head has failed somewhere (or the head itself is open-circuit but hopefully that's not the case). In that situation it would be a good idea to swap the channel cards around and see if the fault moves with the channel card. Assuming they are not soldered in on the R8, of course. If they are socketed it might even be the case that they just need re-seating.

Doesn't seem like it would be the head... but I'm not sure.:facepalm:

I don't know a huge amount about these machines, but I know methodology always pays.
I'd follow JP's whole post, line by line. ;)
 
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